/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp

Bug Summary

File:	tools/clang/lib/Sema/SemaLookup.cpp
Warning:	line 4688, column 3 Use of memory after it is freed

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name SemaLookup.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-eagerly-assume -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -mrelocation-model pic -pic-level 2 -mthread-model posix -relaxed-aliasing -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-7/lib/clang/7.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-7~svn338205/build-llvm/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-7~svn338205/tools/clang/include -I /build/llvm-toolchain-snapshot-7~svn338205/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-7~svn338205/build-llvm/include -I /build/llvm-toolchain-snapshot-7~svn338205/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/8/../../../../include/c++/8 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/8/../../../../include/x86_64-linux-gnu/c++/8 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/8/../../../../include/x86_64-linux-gnu/c++/8 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/8/../../../../include/c++/8/backward -internal-isystem /usr/include/clang/7.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-7/lib/clang/7.0.0/include -internal-externc-isystem /usr/lib/gcc/x86_64-linux-gnu/8/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -O2 -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-comment -std=c++11 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-7~svn338205/build-llvm/tools/clang/lib/Sema -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -fobjc-runtime=gcc -fno-common -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-07-29-043837-17923-1 -x c++ /build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp -faddrsig

/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp

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1//===--------------------- SemaLookup.cpp - Name Lookup  ------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10//  This file implements name lookup for C, C++, Objective-C, and
11//  Objective-C++.
12//
13//===----------------------------------------------------------------------===//

15#include "clang/AST/ASTContext.h"
16#include "clang/AST/CXXInheritance.h"
17#include "clang/AST/Decl.h"
18#include "clang/AST/DeclCXX.h"
19#include "clang/AST/DeclLookups.h"
20#include "clang/AST/DeclObjC.h"
21#include "clang/AST/DeclTemplate.h"
22#include "clang/AST/Expr.h"
23#include "clang/AST/ExprCXX.h"
24#include "clang/Basic/Builtins.h"
25#include "clang/Basic/LangOptions.h"
26#include "clang/Lex/HeaderSearch.h"
27#include "clang/Lex/ModuleLoader.h"
28#include "clang/Lex/Preprocessor.h"
29#include "clang/Sema/DeclSpec.h"
30#include "clang/Sema/Lookup.h"
31#include "clang/Sema/Overload.h"
32#include "clang/Sema/Scope.h"
33#include "clang/Sema/ScopeInfo.h"
34#include "clang/Sema/Sema.h"
35#include "clang/Sema/SemaInternal.h"
36#include "clang/Sema/TemplateDeduction.h"
37#include "clang/Sema/TypoCorrection.h"
38#include "llvm/ADT/STLExtras.h"
39#include "llvm/ADT/SmallPtrSet.h"
40#include "llvm/ADT/TinyPtrVector.h"
41#include "llvm/ADT/edit_distance.h"
42#include "llvm/Support/ErrorHandling.h"
43#include <algorithm>
44#include <iterator>
45#include <list>
46#include <set>
47#include <utility>
48#include <vector>

50using namespace clang;
51using namespace sema;

53namespace {
class UnqualUsingEntry {
  const DeclContext *Nominated;
  const DeclContext *CommonAncestor;

public:
  UnqualUsingEntry(const DeclContext *Nominated,
                   const DeclContext *CommonAncestor)
    : Nominated(Nominated), CommonAncestor(CommonAncestor) {
  }

  const DeclContext *getCommonAncestor() const {
    return CommonAncestor;
  }

  const DeclContext *getNominatedNamespace() const {
    return Nominated;
  }

  // Sort by the pointer value of the common ancestor.
  struct Comparator {
    bool operator()(const UnqualUsingEntry &L, const UnqualUsingEntry &R) {
      return L.getCommonAncestor() < R.getCommonAncestor();
    }

    bool operator()(const UnqualUsingEntry &E, const DeclContext *DC) {
      return E.getCommonAncestor() < DC;
    }

    bool operator()(const DeclContext *DC, const UnqualUsingEntry &E) {
      return DC < E.getCommonAncestor();
    }
  };
};

/// A collection of using directives, as used by C++ unqualified
/// lookup.
class UnqualUsingDirectiveSet {
  Sema &SemaRef;

  typedef SmallVector<UnqualUsingEntry, 8> ListTy;

  ListTy list;
  llvm::SmallPtrSet<DeclContext*, 8> visited;

public:
  UnqualUsingDirectiveSet(Sema &SemaRef) : SemaRef(SemaRef) {}

  void visitScopeChain(Scope *S, Scope *InnermostFileScope) {
    // C++ [namespace.udir]p1:
    //   During unqualified name lookup, the names appear as if they
    //   were declared in the nearest enclosing namespace which contains
    //   both the using-directive and the nominated namespace.
    DeclContext *InnermostFileDC = InnermostFileScope->getEntity();
    assert(InnermostFileDC && InnermostFileDC->isFileContext())(static_cast <bool> (InnermostFileDC && InnermostFileDC
->isFileContext()) ? void (0) : __assert_fail ("InnermostFileDC && InnermostFileDC->isFileContext()"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 107, __extension__ __PRETTY_FUNCTION__));

    for (; S; S = S->getParent()) {
      // C++ [namespace.udir]p1:
      //   A using-directive shall not appear in class scope, but may
      //   appear in namespace scope or in block scope.
      DeclContext *Ctx = S->getEntity();
      if (Ctx && Ctx->isFileContext()) {
        visit(Ctx, Ctx);
      } else if (!Ctx || Ctx->isFunctionOrMethod()) {
        for (auto *I : S->using_directives())
          if (SemaRef.isVisible(I))
            visit(I, InnermostFileDC);
      }
    }
  }

  // Visits a context and collect all of its using directives
  // recursively.  Treats all using directives as if they were
  // declared in the context.
  //
  // A given context is only every visited once, so it is important
  // that contexts be visited from the inside out in order to get
  // the effective DCs right.
  void visit(DeclContext *DC, DeclContext *EffectiveDC) {
    if (!visited.insert(DC).second)
      return;

    addUsingDirectives(DC, EffectiveDC);
  }

  // Visits a using directive and collects all of its using
  // directives recursively.  Treats all using directives as if they
  // were declared in the effective DC.
  void visit(UsingDirectiveDecl *UD, DeclContext *EffectiveDC) {
    DeclContext *NS = UD->getNominatedNamespace();
    if (!visited.insert(NS).second)
      return;

    addUsingDirective(UD, EffectiveDC);
    addUsingDirectives(NS, EffectiveDC);
  }

  // Adds all the using directives in a context (and those nominated
  // by its using directives, transitively) as if they appeared in
  // the given effective context.
  void addUsingDirectives(DeclContext *DC, DeclContext *EffectiveDC) {
    SmallVector<DeclContext*, 4> queue;
    while (true) {
      for (auto UD : DC->using_directives()) {
        DeclContext *NS = UD->getNominatedNamespace();
        if (SemaRef.isVisible(UD) && visited.insert(NS).second) {
          addUsingDirective(UD, EffectiveDC);
          queue.push_back(NS);
        }
      }

      if (queue.empty())
        return;

      DC = queue.pop_back_val();
    }
  }

  // Add a using directive as if it had been declared in the given
  // context.  This helps implement C++ [namespace.udir]p3:
  //   The using-directive is transitive: if a scope contains a
  //   using-directive that nominates a second namespace that itself
  //   contains using-directives, the effect is as if the
  //   using-directives from the second namespace also appeared in
  //   the first.
  void addUsingDirective(UsingDirectiveDecl *UD, DeclContext *EffectiveDC) {
    // Find the common ancestor between the effective context and
    // the nominated namespace.
    DeclContext *Common = UD->getNominatedNamespace();
    while (!Common->Encloses(EffectiveDC))
      Common = Common->getParent();
    Common = Common->getPrimaryContext();

    list.push_back(UnqualUsingEntry(UD->getNominatedNamespace(), Common));
  }

  void done() {
    llvm::sort(list.begin(), list.end(), UnqualUsingEntry::Comparator());
  }

  typedef ListTy::const_iterator const_iterator;

  const_iterator begin() const { return list.begin(); }
  const_iterator end() const { return list.end(); }

  llvm::iterator_range<const_iterator>
  getNamespacesFor(DeclContext *DC) const {
    return llvm::make_range(std::equal_range(begin(), end(),
                                             DC->getPrimaryContext(),
                                             UnqualUsingEntry::Comparator()));
  }
};
205} // end anonymous namespace

207// Retrieve the set of identifier namespaces that correspond to a
208// specific kind of name lookup.
209static inline unsigned getIDNS(Sema::LookupNameKind NameKind,
                             bool CPlusPlus,
                             bool Redeclaration) {
unsigned IDNS = 0;
switch (NameKind) {
case Sema::LookupObjCImplicitSelfParam:
case Sema::LookupOrdinaryName:
case Sema::LookupRedeclarationWithLinkage:
case Sema::LookupLocalFriendName:
  IDNS = Decl::IDNS_Ordinary;
  if (CPlusPlus) {
    IDNS |= Decl::IDNS_Tag | Decl::IDNS_Member | Decl::IDNS_Namespace;
    if (Redeclaration)
      IDNS |= Decl::IDNS_TagFriend | Decl::IDNS_OrdinaryFriend;
  }
  if (Redeclaration)
    IDNS |= Decl::IDNS_LocalExtern;
  break;

case Sema::LookupOperatorName:
  // Operator lookup is its own crazy thing;  it is not the same
  // as (e.g.) looking up an operator name for redeclaration.
  assert(!Redeclaration && "cannot do redeclaration operator lookup")(static_cast <bool> (!Redeclaration && "cannot do redeclaration operator lookup"
) ? void (0) : __assert_fail ("!Redeclaration && \"cannot do redeclaration operator lookup\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 231, __extension__ __PRETTY_FUNCTION__));
  IDNS = Decl::IDNS_NonMemberOperator;
  break;

case Sema::LookupTagName:
  if (CPlusPlus) {
    IDNS = Decl::IDNS_Type;

    // When looking for a redeclaration of a tag name, we add:
    // 1) TagFriend to find undeclared friend decls
    // 2) Namespace because they can't "overload" with tag decls.
    // 3) Tag because it includes class templates, which can't
    //    "overload" with tag decls.
    if (Redeclaration)
      IDNS |= Decl::IDNS_Tag | Decl::IDNS_TagFriend | Decl::IDNS_Namespace;
  } else {
    IDNS = Decl::IDNS_Tag;
  }
  break;

case Sema::LookupLabel:
  IDNS = Decl::IDNS_Label;
  break;

case Sema::LookupMemberName:
  IDNS = Decl::IDNS_Member;
  if (CPlusPlus)
    IDNS |= Decl::IDNS_Tag | Decl::IDNS_Ordinary;
  break;

case Sema::LookupNestedNameSpecifierName:
  IDNS = Decl::IDNS_Type | Decl::IDNS_Namespace;
  break;

case Sema::LookupNamespaceName:
  IDNS = Decl::IDNS_Namespace;
  break;

case Sema::LookupUsingDeclName:
  assert(Redeclaration && "should only be used for redecl lookup")(static_cast <bool> (Redeclaration && "should only be used for redecl lookup"
) ? void (0) : __assert_fail ("Redeclaration && \"should only be used for redecl lookup\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 270, __extension__ __PRETTY_FUNCTION__));
  IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Tag | Decl::IDNS_Member |
         Decl::IDNS_Using | Decl::IDNS_TagFriend | Decl::IDNS_OrdinaryFriend |
         Decl::IDNS_LocalExtern;
  break;

case Sema::LookupObjCProtocolName:
  IDNS = Decl::IDNS_ObjCProtocol;
  break;

case Sema::LookupOMPReductionName:
  IDNS = Decl::IDNS_OMPReduction;
  break;

case Sema::LookupAnyName:
  IDNS = Decl::IDNS_Ordinary | Decl::IDNS_Tag | Decl::IDNS_Member
    | Decl::IDNS_Using | Decl::IDNS_Namespace | Decl::IDNS_ObjCProtocol
    | Decl::IDNS_Type;
  break;
}
return IDNS;
291}

293void LookupResult::configure() {
IDNS = getIDNS(LookupKind, getSema().getLangOpts().CPlusPlus,
               isForRedeclaration());

// If we're looking for one of the allocation or deallocation
// operators, make sure that the implicitly-declared new and delete
// operators can be found.
switch (NameInfo.getName().getCXXOverloadedOperator()) {
case OO_New:
case OO_Delete:
case OO_Array_New:
case OO_Array_Delete:
  getSema().DeclareGlobalNewDelete();
  break;

default:
  break;
}

// Compiler builtins are always visible, regardless of where they end
// up being declared.
if (IdentifierInfo *Id = NameInfo.getName().getAsIdentifierInfo()) {
  if (unsigned BuiltinID = Id->getBuiltinID()) {
    if (!getSema().Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))
      AllowHidden = true;
  }
}
320}

322bool LookupResult::sanity() const {
// This function is never called by NDEBUG builds.
assert(ResultKind != NotFound || Decls.size() == 0)(static_cast <bool> (ResultKind != NotFound || Decls.size
() == 0) ? void (0) : __assert_fail ("ResultKind != NotFound || Decls.size() == 0"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 324, __extension__ __PRETTY_FUNCTION__));
assert(ResultKind != Found || Decls.size() == 1)(static_cast <bool> (ResultKind != Found || Decls.size(
) == 1) ? void (0) : __assert_fail ("ResultKind != Found || Decls.size() == 1"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 325, __extension__ __PRETTY_FUNCTION__));
assert(ResultKind != FoundOverloaded || Decls.size() > 1 ||(static_cast <bool> (ResultKind != FoundOverloaded || Decls
.size() > 1 || (Decls.size() == 1 && isa<FunctionTemplateDecl
>((*begin())->getUnderlyingDecl()))) ? void (0) : __assert_fail
 ("ResultKind != FoundOverloaded || Decls.size() > 1 || (Decls.size() == 1 && isa<FunctionTemplateDecl>((*begin())->getUnderlyingDecl()))"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 328, __extension__ __PRETTY_FUNCTION__))
       (Decls.size() == 1 &&(static_cast <bool> (ResultKind != FoundOverloaded || Decls
.size() > 1 || (Decls.size() == 1 && isa<FunctionTemplateDecl
>((*begin())->getUnderlyingDecl()))) ? void (0) : __assert_fail
 ("ResultKind != FoundOverloaded || Decls.size() > 1 || (Decls.size() == 1 && isa<FunctionTemplateDecl>((*begin())->getUnderlyingDecl()))"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 328, __extension__ __PRETTY_FUNCTION__))
        isa<FunctionTemplateDecl>((*begin())->getUnderlyingDecl())))(static_cast <bool> (ResultKind != FoundOverloaded || Decls
.size() > 1 || (Decls.size() == 1 && isa<FunctionTemplateDecl
>((*begin())->getUnderlyingDecl()))) ? void (0) : __assert_fail
 ("ResultKind != FoundOverloaded || Decls.size() > 1 || (Decls.size() == 1 && isa<FunctionTemplateDecl>((*begin())->getUnderlyingDecl()))"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 328, __extension__ __PRETTY_FUNCTION__));
assert(ResultKind != FoundUnresolvedValue || sanityCheckUnresolved())(static_cast <bool> (ResultKind != FoundUnresolvedValue
 || sanityCheckUnresolved()) ? void (0) : __assert_fail ("ResultKind != FoundUnresolvedValue || sanityCheckUnresolved()"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 329, __extension__ __PRETTY_FUNCTION__));
assert(ResultKind != Ambiguous || Decls.size() > 1 ||(static_cast <bool> (ResultKind != Ambiguous || Decls.size
() > 1 || (Decls.size() == 1 && (Ambiguity == AmbiguousBaseSubobjects
 || Ambiguity == AmbiguousBaseSubobjectTypes))) ? void (0) : __assert_fail
 ("ResultKind != Ambiguous || Decls.size() > 1 || (Decls.size() == 1 && (Ambiguity == AmbiguousBaseSubobjects || Ambiguity == AmbiguousBaseSubobjectTypes))"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 332, __extension__ __PRETTY_FUNCTION__))
       (Decls.size() == 1 && (Ambiguity == AmbiguousBaseSubobjects ||(static_cast <bool> (ResultKind != Ambiguous || Decls.size
() > 1 || (Decls.size() == 1 && (Ambiguity == AmbiguousBaseSubobjects
 || Ambiguity == AmbiguousBaseSubobjectTypes))) ? void (0) : __assert_fail
 ("ResultKind != Ambiguous || Decls.size() > 1 || (Decls.size() == 1 && (Ambiguity == AmbiguousBaseSubobjects || Ambiguity == AmbiguousBaseSubobjectTypes))"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 332, __extension__ __PRETTY_FUNCTION__))
                              Ambiguity == AmbiguousBaseSubobjectTypes)))(static_cast <bool> (ResultKind != Ambiguous || Decls.size
() > 1 || (Decls.size() == 1 && (Ambiguity == AmbiguousBaseSubobjects
 || Ambiguity == AmbiguousBaseSubobjectTypes))) ? void (0) : __assert_fail
 ("ResultKind != Ambiguous || Decls.size() > 1 || (Decls.size() == 1 && (Ambiguity == AmbiguousBaseSubobjects || Ambiguity == AmbiguousBaseSubobjectTypes))"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 332, __extension__ __PRETTY_FUNCTION__));
assert((Paths != nullptr) == (ResultKind == Ambiguous &&(static_cast <bool> ((Paths != nullptr) == (ResultKind ==
 Ambiguous && (Ambiguity == AmbiguousBaseSubobjectTypes
 || Ambiguity == AmbiguousBaseSubobjects))) ? void (0) : __assert_fail
 ("(Paths != nullptr) == (ResultKind == Ambiguous && (Ambiguity == AmbiguousBaseSubobjectTypes || Ambiguity == AmbiguousBaseSubobjects))"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 335, __extension__ __PRETTY_FUNCTION__))
                              (Ambiguity == AmbiguousBaseSubobjectTypes ||(static_cast <bool> ((Paths != nullptr) == (ResultKind ==
 Ambiguous && (Ambiguity == AmbiguousBaseSubobjectTypes
 || Ambiguity == AmbiguousBaseSubobjects))) ? void (0) : __assert_fail
 ("(Paths != nullptr) == (ResultKind == Ambiguous && (Ambiguity == AmbiguousBaseSubobjectTypes || Ambiguity == AmbiguousBaseSubobjects))"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 335, __extension__ __PRETTY_FUNCTION__))
                               Ambiguity == AmbiguousBaseSubobjects)))(static_cast <bool> ((Paths != nullptr) == (ResultKind ==
 Ambiguous && (Ambiguity == AmbiguousBaseSubobjectTypes
 || Ambiguity == AmbiguousBaseSubobjects))) ? void (0) : __assert_fail
 ("(Paths != nullptr) == (ResultKind == Ambiguous && (Ambiguity == AmbiguousBaseSubobjectTypes || Ambiguity == AmbiguousBaseSubobjects))"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 335, __extension__ __PRETTY_FUNCTION__));
return true;
337}

339// Necessary because CXXBasePaths is not complete in Sema.h
340void LookupResult::deletePaths(CXXBasePaths *Paths) {
delete Paths;
342}

344/// Get a representative context for a declaration such that two declarations
345/// will have the same context if they were found within the same scope.
346static DeclContext *getContextForScopeMatching(Decl *D) {
// For function-local declarations, use that function as the context. This
// doesn't account for scopes within the function; the caller must deal with
// those.
DeclContext *DC = D->getLexicalDeclContext();
if (DC->isFunctionOrMethod())
  return DC;

// Otherwise, look at the semantic context of the declaration. The
// declaration must have been found there.
return D->getDeclContext()->getRedeclContext();
357}

359/// Determine whether \p D is a better lookup result than \p Existing,
360/// given that they declare the same entity.
361static bool isPreferredLookupResult(Sema &S, Sema::LookupNameKind Kind,
                                  NamedDecl *D, NamedDecl *Existing) {
// When looking up redeclarations of a using declaration, prefer a using
// shadow declaration over any other declaration of the same entity.
if (Kind == Sema::LookupUsingDeclName && isa<UsingShadowDecl>(D) &&
    !isa<UsingShadowDecl>(Existing))
  return true;

auto *DUnderlying = D->getUnderlyingDecl();
auto *EUnderlying = Existing->getUnderlyingDecl();

// If they have different underlying declarations, prefer a typedef over the
// original type (this happens when two type declarations denote the same
// type), per a generous reading of C++ [dcl.typedef]p3 and p4. The typedef
// might carry additional semantic information, such as an alignment override.
// However, per C++ [dcl.typedef]p5, when looking up a tag name, prefer a tag
// declaration over a typedef.
if (DUnderlying->getCanonicalDecl() != EUnderlying->getCanonicalDecl()) {
  assert(isa<TypeDecl>(DUnderlying) && isa<TypeDecl>(EUnderlying))(static_cast <bool> (isa<TypeDecl>(DUnderlying) &&
 isa<TypeDecl>(EUnderlying)) ? void (0) : __assert_fail
 ("isa<TypeDecl>(DUnderlying) && isa<TypeDecl>(EUnderlying)"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 379, __extension__ __PRETTY_FUNCTION__));
  bool HaveTag = isa<TagDecl>(EUnderlying);
  bool WantTag = Kind == Sema::LookupTagName;
  return HaveTag != WantTag;
}

// Pick the function with more default arguments.
// FIXME: In the presence of ambiguous default arguments, we should keep both,
//        so we can diagnose the ambiguity if the default argument is needed.
//        See C++ [over.match.best]p3.
if (auto *DFD = dyn_cast<FunctionDecl>(DUnderlying)) {
  auto *EFD = cast<FunctionDecl>(EUnderlying);
  unsigned DMin = DFD->getMinRequiredArguments();
  unsigned EMin = EFD->getMinRequiredArguments();
  // If D has more default arguments, it is preferred.
  if (DMin != EMin)
    return DMin < EMin;
  // FIXME: When we track visibility for default function arguments, check
  // that we pick the declaration with more visible default arguments.
}

// Pick the template with more default template arguments.
if (auto *DTD = dyn_cast<TemplateDecl>(DUnderlying)) {
  auto *ETD = cast<TemplateDecl>(EUnderlying);
  unsigned DMin = DTD->getTemplateParameters()->getMinRequiredArguments();
  unsigned EMin = ETD->getTemplateParameters()->getMinRequiredArguments();
  // If D has more default arguments, it is preferred. Note that default
  // arguments (and their visibility) is monotonically increasing across the
  // redeclaration chain, so this is a quick proxy for "is more recent".
  if (DMin != EMin)
    return DMin < EMin;
  // If D has more *visible* default arguments, it is preferred. Note, an
  // earlier default argument being visible does not imply that a later
  // default argument is visible, so we can't just check the first one.
  for (unsigned I = DMin, N = DTD->getTemplateParameters()->size();
      I != N; ++I) {
    if (!S.hasVisibleDefaultArgument(
            ETD->getTemplateParameters()->getParam(I)) &&
        S.hasVisibleDefaultArgument(
            DTD->getTemplateParameters()->getParam(I)))
      return true;
  }
}

// VarDecl can have incomplete array types, prefer the one with more complete
// array type.
if (VarDecl *DVD = dyn_cast<VarDecl>(DUnderlying)) {
  VarDecl *EVD = cast<VarDecl>(EUnderlying);
  if (EVD->getType()->isIncompleteType() &&
      !DVD->getType()->isIncompleteType()) {
    // Prefer the decl with a more complete type if visible.
    return S.isVisible(DVD);
  }
  return false; // Avoid picking up a newer decl, just because it was newer.
}

// For most kinds of declaration, it doesn't really matter which one we pick.
if (!isa<FunctionDecl>(DUnderlying) && !isa<VarDecl>(DUnderlying)) {
  // If the existing declaration is hidden, prefer the new one. Otherwise,
  // keep what we've got.
  return !S.isVisible(Existing);
}

// Pick the newer declaration; it might have a more precise type.
for (Decl *Prev = DUnderlying->getPreviousDecl(); Prev;
     Prev = Prev->getPreviousDecl())
  if (Prev == EUnderlying)
    return true;
return false;
448}

450/// Determine whether \p D can hide a tag declaration.
451static bool canHideTag(NamedDecl *D) {
// C++ [basic.scope.declarative]p4:
//   Given a set of declarations in a single declarative region [...]
//   exactly one declaration shall declare a class name or enumeration name
//   that is not a typedef name and the other declarations shall all refer to
//   the same variable, non-static data member, or enumerator, or all refer
//   to functions and function templates; in this case the class name or
//   enumeration name is hidden.
// C++ [basic.scope.hiding]p2:
//   A class name or enumeration name can be hidden by the name of a
//   variable, data member, function, or enumerator declared in the same
//   scope.
// An UnresolvedUsingValueDecl always instantiates to one of these.
D = D->getUnderlyingDecl();
return isa<VarDecl>(D) || isa<EnumConstantDecl>(D) || isa<FunctionDecl>(D) ||
       isa<FunctionTemplateDecl>(D) || isa<FieldDecl>(D) ||
       isa<UnresolvedUsingValueDecl>(D);
468}

470/// Resolves the result kind of this lookup.
471void LookupResult::resolveKind() {
unsigned N = Decls.size();

// Fast case: no possible ambiguity.
if (N == 0) {
  assert(ResultKind == NotFound ||(static_cast <bool> (ResultKind == NotFound || ResultKind
 == NotFoundInCurrentInstantiation) ? void (0) : __assert_fail
 ("ResultKind == NotFound || ResultKind == NotFoundInCurrentInstantiation"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 477, __extension__ __PRETTY_FUNCTION__))
         ResultKind == NotFoundInCurrentInstantiation)(static_cast <bool> (ResultKind == NotFound || ResultKind
 == NotFoundInCurrentInstantiation) ? void (0) : __assert_fail
 ("ResultKind == NotFound || ResultKind == NotFoundInCurrentInstantiation"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 477, __extension__ __PRETTY_FUNCTION__));
  return;
}

// If there's a single decl, we need to examine it to decide what
// kind of lookup this is.
if (N == 1) {
  NamedDecl *D = (*Decls.begin())->getUnderlyingDecl();
  if (isa<FunctionTemplateDecl>(D))
    ResultKind = FoundOverloaded;
  else if (isa<UnresolvedUsingValueDecl>(D))
    ResultKind = FoundUnresolvedValue;
  return;
}

// Don't do any extra resolution if we've already resolved as ambiguous.
if (ResultKind == Ambiguous) return;

llvm::SmallDenseMap<NamedDecl*, unsigned, 16> Unique;
llvm::SmallDenseMap<QualType, unsigned, 16> UniqueTypes;

bool Ambiguous = false;
bool HasTag = false, HasFunction = false;
bool HasFunctionTemplate = false, HasUnresolved = false;
NamedDecl *HasNonFunction = nullptr;

llvm::SmallVector<NamedDecl*, 4> EquivalentNonFunctions;

unsigned UniqueTagIndex = 0;

unsigned I = 0;
while (I < N) {
  NamedDecl *D = Decls[I]->getUnderlyingDecl();
  D = cast<NamedDecl>(D->getCanonicalDecl());

  // Ignore an invalid declaration unless it's the only one left.
  if (D->isInvalidDecl() && !(I == 0 && N == 1)) {
    Decls[I] = Decls[--N];
    continue;
  }

  llvm::Optional<unsigned> ExistingI;

  // Redeclarations of types via typedef can occur both within a scope
  // and, through using declarations and directives, across scopes. There is
  // no ambiguity if they all refer to the same type, so unique based on the
  // canonical type.
  if (TypeDecl *TD = dyn_cast<TypeDecl>(D)) {
    QualType T = getSema().Context.getTypeDeclType(TD);
    auto UniqueResult = UniqueTypes.insert(
        std::make_pair(getSema().Context.getCanonicalType(T), I));
    if (!UniqueResult.second) {
      // The type is not unique.
      ExistingI = UniqueResult.first->second;
    }
  }

  // For non-type declarations, check for a prior lookup result naming this
  // canonical declaration.
  if (!ExistingI) {
    auto UniqueResult = Unique.insert(std::make_pair(D, I));
    if (!UniqueResult.second) {
      // We've seen this entity before.
      ExistingI = UniqueResult.first->second;
    }
  }

  if (ExistingI) {
    // This is not a unique lookup result. Pick one of the results and
    // discard the other.
    if (isPreferredLookupResult(getSema(), getLookupKind(), Decls[I],
                                Decls[*ExistingI]))
      Decls[*ExistingI] = Decls[I];
    Decls[I] = Decls[--N];
    continue;
  }

  // Otherwise, do some decl type analysis and then continue.

  if (isa<UnresolvedUsingValueDecl>(D)) {
    HasUnresolved = true;
  } else if (isa<TagDecl>(D)) {
    if (HasTag)
      Ambiguous = true;
    UniqueTagIndex = I;
    HasTag = true;
  } else if (isa<FunctionTemplateDecl>(D)) {
    HasFunction = true;
    HasFunctionTemplate = true;
  } else if (isa<FunctionDecl>(D)) {
    HasFunction = true;
  } else {
    if (HasNonFunction) {
      // If we're about to create an ambiguity between two declarations that
      // are equivalent, but one is an internal linkage declaration from one
      // module and the other is an internal linkage declaration from another
      // module, just skip it.
      if (getSema().isEquivalentInternalLinkageDeclaration(HasNonFunction,
                                                           D)) {
        EquivalentNonFunctions.push_back(D);
        Decls[I] = Decls[--N];
        continue;
      }

      Ambiguous = true;
    }
    HasNonFunction = D;
  }
  I++;
}

// C++ [basic.scope.hiding]p2:
//   A class name or enumeration name can be hidden by the name of
//   an object, function, or enumerator declared in the same
//   scope. If a class or enumeration name and an object, function,
//   or enumerator are declared in the same scope (in any order)
//   with the same name, the class or enumeration name is hidden
//   wherever the object, function, or enumerator name is visible.
// But it's still an error if there are distinct tag types found,
// even if they're not visible. (ref?)
if (N > 1 && HideTags && HasTag && !Ambiguous &&
    (HasFunction || HasNonFunction || HasUnresolved)) {
  NamedDecl *OtherDecl = Decls[UniqueTagIndex ? 0 : N - 1];
  if (isa<TagDecl>(Decls[UniqueTagIndex]->getUnderlyingDecl()) &&
      getContextForScopeMatching(Decls[UniqueTagIndex])->Equals(
          getContextForScopeMatching(OtherDecl)) &&
      canHideTag(OtherDecl))
    Decls[UniqueTagIndex] = Decls[--N];
  else
    Ambiguous = true;
}

// FIXME: This diagnostic should really be delayed until we're done with
// the lookup result, in case the ambiguity is resolved by the caller.
if (!EquivalentNonFunctions.empty() && !Ambiguous)
  getSema().diagnoseEquivalentInternalLinkageDeclarations(
      getNameLoc(), HasNonFunction, EquivalentNonFunctions);

Decls.set_size(N);

if (HasNonFunction && (HasFunction || HasUnresolved))
  Ambiguous = true;

if (Ambiguous)
  setAmbiguous(LookupResult::AmbiguousReference);
else if (HasUnresolved)
  ResultKind = LookupResult::FoundUnresolvedValue;
else if (N > 1 || HasFunctionTemplate)
  ResultKind = LookupResult::FoundOverloaded;
else
  ResultKind = LookupResult::Found;
628}

630void LookupResult::addDeclsFromBasePaths(const CXXBasePaths &P) {
CXXBasePaths::const_paths_iterator I, E;
for (I = P.begin(), E = P.end(); I != E; ++I)
  for (DeclContext::lookup_iterator DI = I->Decls.begin(),
       DE = I->Decls.end(); DI != DE; ++DI)
    addDecl(*DI);
636}

638void LookupResult::setAmbiguousBaseSubobjects(CXXBasePaths &P) {
Paths = new CXXBasePaths;
Paths->swap(P);
addDeclsFromBasePaths(*Paths);
resolveKind();
setAmbiguous(AmbiguousBaseSubobjects);
644}

646void LookupResult::setAmbiguousBaseSubobjectTypes(CXXBasePaths &P) {
Paths = new CXXBasePaths;
Paths->swap(P);
addDeclsFromBasePaths(*Paths);
resolveKind();
setAmbiguous(AmbiguousBaseSubobjectTypes);
652}

654void LookupResult::print(raw_ostream &Out) {
Out << Decls.size() << " result(s)";
if (isAmbiguous()) Out << ", ambiguous";
if (Paths) Out << ", base paths present";

for (iterator I = begin(), E = end(); I != E; ++I) {
  Out << "\n";
  (*I)->print(Out, 2);
}
663}

665LLVM_DUMP_METHOD__attribute__((noinline)) __attribute__((__used__)) void LookupResult::dump() {
llvm::errs() << "lookup results for " << getLookupName().getAsString()
             << ":\n";
for (NamedDecl *D : *this)
  D->dump();
670}

672/// Lookup a builtin function, when name lookup would otherwise
673/// fail.
674static bool LookupBuiltin(Sema &S, LookupResult &R) {
Sema::LookupNameKind NameKind = R.getLookupKind();

// If we didn't find a use of this identifier, and if the identifier
// corresponds to a compiler builtin, create the decl object for the builtin
// now, injecting it into translation unit scope, and return it.
if (NameKind == Sema::LookupOrdinaryName ||
    NameKind == Sema::LookupRedeclarationWithLinkage) {
  IdentifierInfo *II = R.getLookupName().getAsIdentifierInfo();
  if (II) {
    if (S.getLangOpts().CPlusPlus && NameKind == Sema::LookupOrdinaryName) {
      if (II == S.getASTContext().getMakeIntegerSeqName()) {
        R.addDecl(S.getASTContext().getMakeIntegerSeqDecl());
        return true;
      } else if (II == S.getASTContext().getTypePackElementName()) {
        R.addDecl(S.getASTContext().getTypePackElementDecl());
        return true;
      }
    }

    // If this is a builtin on this (or all) targets, create the decl.
    if (unsigned BuiltinID = II->getBuiltinID()) {
      // In C++ and OpenCL (spec v1.2 s6.9.f), we don't have any predefined
      // library functions like 'malloc'. Instead, we'll just error.
      if ((S.getLangOpts().CPlusPlus || S.getLangOpts().OpenCL) &&
          S.Context.BuiltinInfo.isPredefinedLibFunction(BuiltinID))
        return false;

      if (NamedDecl *D = S.LazilyCreateBuiltin((IdentifierInfo *)II,
                                               BuiltinID, S.TUScope,
                                               R.isForRedeclaration(),
                                               R.getNameLoc())) {
        R.addDecl(D);
        return true;
      }
    }
  }
}

return false;
714}

716/// Determine whether we can declare a special member function within
717/// the class at this point.
718static bool CanDeclareSpecialMemberFunction(const CXXRecordDecl *Class) {
// We need to have a definition for the class.
if (!Class->getDefinition() || Class->isDependentContext())
  return false;

// We can't be in the middle of defining the class.
return !Class->isBeingDefined();
725}

727void Sema::ForceDeclarationOfImplicitMembers(CXXRecordDecl *Class) {
if (!CanDeclareSpecialMemberFunction(Class))
  return;

// If the default constructor has not yet been declared, do so now.
if (Class->needsImplicitDefaultConstructor())
  DeclareImplicitDefaultConstructor(Class);

// If the copy constructor has not yet been declared, do so now.
if (Class->needsImplicitCopyConstructor())
  DeclareImplicitCopyConstructor(Class);

// If the copy assignment operator has not yet been declared, do so now.
if (Class->needsImplicitCopyAssignment())
  DeclareImplicitCopyAssignment(Class);

if (getLangOpts().CPlusPlus11) {
  // If the move constructor has not yet been declared, do so now.
  if (Class->needsImplicitMoveConstructor())
    DeclareImplicitMoveConstructor(Class);

  // If the move assignment operator has not yet been declared, do so now.
  if (Class->needsImplicitMoveAssignment())
    DeclareImplicitMoveAssignment(Class);
}

// If the destructor has not yet been declared, do so now.
if (Class->needsImplicitDestructor())
  DeclareImplicitDestructor(Class);
756}

758/// Determine whether this is the name of an implicitly-declared
759/// special member function.
760static bool isImplicitlyDeclaredMemberFunctionName(DeclarationName Name) {
switch (Name.getNameKind()) {
case DeclarationName::CXXConstructorName:
case DeclarationName::CXXDestructorName:
  return true;

case DeclarationName::CXXOperatorName:
  return Name.getCXXOverloadedOperator() == OO_Equal;

default:
  break;
}

return false;
774}

776/// If there are any implicit member functions with the given name
777/// that need to be declared in the given declaration context, do so.
778static void DeclareImplicitMemberFunctionsWithName(Sema &S,
                                                 DeclarationName Name,
                                                 SourceLocation Loc,
                                                 const DeclContext *DC) {
if (!DC)
  return;

switch (Name.getNameKind()) {
case DeclarationName::CXXConstructorName:
  if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
    if (Record->getDefinition() && CanDeclareSpecialMemberFunction(Record)) {
      CXXRecordDecl *Class = const_cast<CXXRecordDecl *>(Record);
      if (Record->needsImplicitDefaultConstructor())
        S.DeclareImplicitDefaultConstructor(Class);
      if (Record->needsImplicitCopyConstructor())
        S.DeclareImplicitCopyConstructor(Class);
      if (S.getLangOpts().CPlusPlus11 &&
          Record->needsImplicitMoveConstructor())
        S.DeclareImplicitMoveConstructor(Class);
    }
  break;

case DeclarationName::CXXDestructorName:
  if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC))
    if (Record->getDefinition() && Record->needsImplicitDestructor() &&
        CanDeclareSpecialMemberFunction(Record))
      S.DeclareImplicitDestructor(const_cast<CXXRecordDecl *>(Record));
  break;

case DeclarationName::CXXOperatorName:
  if (Name.getCXXOverloadedOperator() != OO_Equal)
    break;

  if (const CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(DC)) {
    if (Record->getDefinition() && CanDeclareSpecialMemberFunction(Record)) {
      CXXRecordDecl *Class = const_cast<CXXRecordDecl *>(Record);
      if (Record->needsImplicitCopyAssignment())
        S.DeclareImplicitCopyAssignment(Class);
      if (S.getLangOpts().CPlusPlus11 &&
          Record->needsImplicitMoveAssignment())
        S.DeclareImplicitMoveAssignment(Class);
    }
  }
  break;

case DeclarationName::CXXDeductionGuideName:
  S.DeclareImplicitDeductionGuides(Name.getCXXDeductionGuideTemplate(), Loc);
  break;

default:
  break;
}
830}

832// Adds all qualifying matches for a name within a decl context to the
833// given lookup result.  Returns true if any matches were found.
834static bool LookupDirect(Sema &S, LookupResult &R, const DeclContext *DC) {
bool Found = false;

// Lazily declare C++ special member functions.
if (S.getLangOpts().CPlusPlus)
  DeclareImplicitMemberFunctionsWithName(S, R.getLookupName(), R.getNameLoc(),
                                         DC);

// Perform lookup into this declaration context.
DeclContext::lookup_result DR = DC->lookup(R.getLookupName());
for (NamedDecl *D : DR) {
  if ((D = R.getAcceptableDecl(D))) {
    R.addDecl(D);
    Found = true;
  }
}

if (!Found && DC->isTranslationUnit() && LookupBuiltin(S, R))
  return true;

if (R.getLookupName().getNameKind()
      != DeclarationName::CXXConversionFunctionName ||
    R.getLookupName().getCXXNameType()->isDependentType() ||
    !isa<CXXRecordDecl>(DC))
  return Found;

// C++ [temp.mem]p6:
//   A specialization of a conversion function template is not found by
//   name lookup. Instead, any conversion function templates visible in the
//   context of the use are considered. [...]
const CXXRecordDecl *Record = cast<CXXRecordDecl>(DC);
if (!Record->isCompleteDefinition())
  return Found;

// For conversion operators, 'operator auto' should only match
// 'operator auto'.  Since 'auto' is not a type, it shouldn't be considered
// as a candidate for template substitution.
auto *ContainedDeducedType =
    R.getLookupName().getCXXNameType()->getContainedDeducedType();
if (R.getLookupName().getNameKind() ==
        DeclarationName::CXXConversionFunctionName &&
    ContainedDeducedType && ContainedDeducedType->isUndeducedType())
  return Found;

for (CXXRecordDecl::conversion_iterator U = Record->conversion_begin(),
       UEnd = Record->conversion_end(); U != UEnd; ++U) {
  FunctionTemplateDecl *ConvTemplate = dyn_cast<FunctionTemplateDecl>(*U);
  if (!ConvTemplate)
    continue;

  // When we're performing lookup for the purposes of redeclaration, just
  // add the conversion function template. When we deduce template
  // arguments for specializations, we'll end up unifying the return
  // type of the new declaration with the type of the function template.
  if (R.isForRedeclaration()) {
    R.addDecl(ConvTemplate);
    Found = true;
    continue;
  }

  // C++ [temp.mem]p6:
  //   [...] For each such operator, if argument deduction succeeds
  //   (14.9.2.3), the resulting specialization is used as if found by
  //   name lookup.
  //
  // When referencing a conversion function for any purpose other than
  // a redeclaration (such that we'll be building an expression with the
  // result), perform template argument deduction and place the
  // specialization into the result set. We do this to avoid forcing all
  // callers to perform special deduction for conversion functions.
  TemplateDeductionInfo Info(R.getNameLoc());
  FunctionDecl *Specialization = nullptr;

  const FunctionProtoType *ConvProto
    = ConvTemplate->getTemplatedDecl()->getType()->getAs<FunctionProtoType>();
  assert(ConvProto && "Nonsensical conversion function template type")(static_cast <bool> (ConvProto && "Nonsensical conversion function template type"
) ? void (0) : __assert_fail ("ConvProto && \"Nonsensical conversion function template type\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 909, __extension__ __PRETTY_FUNCTION__));

  // Compute the type of the function that we would expect the conversion
  // function to have, if it were to match the name given.
  // FIXME: Calling convention!
  FunctionProtoType::ExtProtoInfo EPI = ConvProto->getExtProtoInfo();
  EPI.ExtInfo = EPI.ExtInfo.withCallingConv(CC_C);
  EPI.ExceptionSpec = EST_None;
  QualType ExpectedType
    = R.getSema().Context.getFunctionType(R.getLookupName().getCXXNameType(),
                                          None, EPI);

  // Perform template argument deduction against the type that we would
  // expect the function to have.
  if (R.getSema().DeduceTemplateArguments(ConvTemplate, nullptr, ExpectedType,
                                          Specialization, Info)
        == Sema::TDK_Success) {
    R.addDecl(Specialization);
    Found = true;
  }
}

return Found;
932}

934// Performs C++ unqualified lookup into the given file context.
935static bool
936CppNamespaceLookup(Sema &S, LookupResult &R, ASTContext &Context,
                 DeclContext *NS, UnqualUsingDirectiveSet &UDirs) {

assert(NS && NS->isFileContext() && "CppNamespaceLookup() requires namespace!")(static_cast <bool> (NS && NS->isFileContext
() && "CppNamespaceLookup() requires namespace!") ? void
 (0) : __assert_fail ("NS && NS->isFileContext() && \"CppNamespaceLookup() requires namespace!\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 939, __extension__ __PRETTY_FUNCTION__));

// Perform direct name lookup into the LookupCtx.
bool Found = LookupDirect(S, R, NS);

// Perform direct name lookup into the namespaces nominated by the
// using directives whose common ancestor is this namespace.
for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(NS))
  if (LookupDirect(S, R, UUE.getNominatedNamespace()))
    Found = true;

R.resolveKind();

return Found;
953}

955static bool isNamespaceOrTranslationUnitScope(Scope *S) {
if (DeclContext *Ctx = S->getEntity())
  return Ctx->isFileContext();
return false;
959}

961// Find the next outer declaration context from this scope. This
962// routine actually returns the semantic outer context, which may
963// differ from the lexical context (encoded directly in the Scope
964// stack) when we are parsing a member of a class template. In this
965// case, the second element of the pair will be true, to indicate that
966// name lookup should continue searching in this semantic context when
967// it leaves the current template parameter scope.
968static std::pair<DeclContext *, bool> findOuterContext(Scope *S) {
DeclContext *DC = S->getEntity();
DeclContext *Lexical = nullptr;
for (Scope *OuterS = S->getParent(); OuterS;
     OuterS = OuterS->getParent()) {
  if (OuterS->getEntity()) {
    Lexical = OuterS->getEntity();
    break;
  }
}

// C++ [temp.local]p8:
//   In the definition of a member of a class template that appears
//   outside of the namespace containing the class template
//   definition, the name of a template-parameter hides the name of
//   a member of this namespace.
//
// Example:
//
//   namespace N {
//     class C { };
//
//     template<class T> class B {
//       void f(T);
//     };
//   }
//
//   template<class C> void N::B<C>::f(C) {
//     C b;  // C is the template parameter, not N::C
//   }
//
// In this example, the lexical context we return is the
// TranslationUnit, while the semantic context is the namespace N.
if (!Lexical || !DC || !S->getParent() ||
    !S->getParent()->isTemplateParamScope())
  return std::make_pair(Lexical, false);

// Find the outermost template parameter scope.
// For the example, this is the scope for the template parameters of
// template<class C>.
Scope *OutermostTemplateScope = S->getParent();
while (OutermostTemplateScope->getParent() &&
       OutermostTemplateScope->getParent()->isTemplateParamScope())
  OutermostTemplateScope = OutermostTemplateScope->getParent();

// Find the namespace context in which the original scope occurs. In
// the example, this is namespace N.
DeclContext *Semantic = DC;
while (!Semantic->isFileContext())
  Semantic = Semantic->getParent();

// Find the declaration context just outside of the template
// parameter scope. This is the context in which the template is
// being lexically declaration (a namespace context). In the
// example, this is the global scope.
if (Lexical->isFileContext() && !Lexical->Equals(Semantic) &&
    Lexical->Encloses(Semantic))
  return std::make_pair(Semantic, true);

return std::make_pair(Lexical, false);
1028}

1030namespace {
1031/// An RAII object to specify that we want to find block scope extern
1032/// declarations.
1033struct FindLocalExternScope {
FindLocalExternScope(LookupResult &R)
    : R(R), OldFindLocalExtern(R.getIdentifierNamespace() &
                               Decl::IDNS_LocalExtern) {
  R.setFindLocalExtern(R.getIdentifierNamespace() &
                       (Decl::IDNS_Ordinary | Decl::IDNS_NonMemberOperator));
}
void restore() {
  R.setFindLocalExtern(OldFindLocalExtern);
}
~FindLocalExternScope() {
  restore();
}
LookupResult &R;
bool OldFindLocalExtern;
1048};
1049} // end anonymous namespace

1051bool Sema::CppLookupName(LookupResult &R, Scope *S) {
assert(getLangOpts().CPlusPlus && "Can perform only C++ lookup")(static_cast <bool> (getLangOpts().CPlusPlus &&
 "Can perform only C++ lookup") ? void (0) : __assert_fail ("getLangOpts().CPlusPlus && \"Can perform only C++ lookup\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1052, __extension__ __PRETTY_FUNCTION__));

DeclarationName Name = R.getLookupName();
Sema::LookupNameKind NameKind = R.getLookupKind();

// If this is the name of an implicitly-declared special member function,
// go through the scope stack to implicitly declare
if (isImplicitlyDeclaredMemberFunctionName(Name)) {
  for (Scope *PreS = S; PreS; PreS = PreS->getParent())
    if (DeclContext *DC = PreS->getEntity())
      DeclareImplicitMemberFunctionsWithName(*this, Name, R.getNameLoc(), DC);
}

// Implicitly declare member functions with the name we're looking for, if in
// fact we are in a scope where it matters.

Scope *Initial = S;
IdentifierResolver::iterator
  I = IdResolver.begin(Name),
  IEnd = IdResolver.end();

// First we lookup local scope.
// We don't consider using-directives, as per 7.3.4.p1 [namespace.udir]
// ...During unqualified name lookup (3.4.1), the names appear as if
// they were declared in the nearest enclosing namespace which contains
// both the using-directive and the nominated namespace.
// [Note: in this context, "contains" means "contains directly or
// indirectly".
//
// For example:
// namespace A { int i; }
// void foo() {
//   int i;
//   {
//     using namespace A;
//     ++i; // finds local 'i', A::i appears at global scope
//   }
// }
//
UnqualUsingDirectiveSet UDirs(*this);
bool VisitedUsingDirectives = false;
bool LeftStartingScope = false;
DeclContext *OutsideOfTemplateParamDC = nullptr;

// When performing a scope lookup, we want to find local extern decls.
FindLocalExternScope FindLocals(R);

for (; S && !isNamespaceOrTranslationUnitScope(S); S = S->getParent()) {
  DeclContext *Ctx = S->getEntity();
  bool SearchNamespaceScope = true;
  // Check whether the IdResolver has anything in this scope.
  for (; I != IEnd && S->isDeclScope(*I); ++I) {
    if (NamedDecl *ND = R.getAcceptableDecl(*I)) {
      if (NameKind == LookupRedeclarationWithLinkage &&
          !(*I)->isTemplateParameter()) {
        // If it's a template parameter, we still find it, so we can diagnose
        // the invalid redeclaration.

        // Determine whether this (or a previous) declaration is
        // out-of-scope.
        if (!LeftStartingScope && !Initial->isDeclScope(*I))
          LeftStartingScope = true;

        // If we found something outside of our starting scope that
        // does not have linkage, skip it.
        if (LeftStartingScope && !((*I)->hasLinkage())) {
          R.setShadowed();
          continue;
        }
      } else {
        // We found something in this scope, we should not look at the
        // namespace scope
        SearchNamespaceScope = false;
      }
      R.addDecl(ND);
    }
  }
  if (!SearchNamespaceScope) {
    R.resolveKind();
    if (S->isClassScope())
      if (CXXRecordDecl *Record = dyn_cast_or_null<CXXRecordDecl>(Ctx))
        R.setNamingClass(Record);
    return true;
  }

  if (NameKind == LookupLocalFriendName && !S->isClassScope()) {
    // C++11 [class.friend]p11:
    //   If a friend declaration appears in a local class and the name
    //   specified is an unqualified name, a prior declaration is
    //   looked up without considering scopes that are outside the
    //   innermost enclosing non-class scope.
    return false;
  }

  if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC &&
      S->getParent() && !S->getParent()->isTemplateParamScope()) {
    // We've just searched the last template parameter scope and
    // found nothing, so look into the contexts between the
    // lexical and semantic declaration contexts returned by
    // findOuterContext(). This implements the name lookup behavior
    // of C++ [temp.local]p8.
    Ctx = OutsideOfTemplateParamDC;
    OutsideOfTemplateParamDC = nullptr;
  }

  if (Ctx) {
    DeclContext *OuterCtx;
    bool SearchAfterTemplateScope;
    std::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S);
    if (SearchAfterTemplateScope)
      OutsideOfTemplateParamDC = OuterCtx;

    for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) {
      // We do not directly look into transparent contexts, since
      // those entities will be found in the nearest enclosing
      // non-transparent context.
      if (Ctx->isTransparentContext())
        continue;

      // We do not look directly into function or method contexts,
      // since all of the local variables and parameters of the
      // function/method are present within the Scope.
      if (Ctx->isFunctionOrMethod()) {
        // If we have an Objective-C instance method, look for ivars
        // in the corresponding interface.
        if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
          if (Method->isInstanceMethod() && Name.getAsIdentifierInfo())
            if (ObjCInterfaceDecl *Class = Method->getClassInterface()) {
              ObjCInterfaceDecl *ClassDeclared;
              if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(
                                               Name.getAsIdentifierInfo(),
                                                           ClassDeclared)) {
                if (NamedDecl *ND = R.getAcceptableDecl(Ivar)) {
                  R.addDecl(ND);
                  R.resolveKind();
                  return true;
                }
              }
            }
        }

        continue;
      }

      // If this is a file context, we need to perform unqualified name
      // lookup considering using directives.
      if (Ctx->isFileContext()) {
        // If we haven't handled using directives yet, do so now.
        if (!VisitedUsingDirectives) {
          // Add using directives from this context up to the top level.
          for (DeclContext *UCtx = Ctx; UCtx; UCtx = UCtx->getParent()) {
            if (UCtx->isTransparentContext())
              continue;

            UDirs.visit(UCtx, UCtx);
          }

          // Find the innermost file scope, so we can add using directives
          // from local scopes.
          Scope *InnermostFileScope = S;
          while (InnermostFileScope &&
                 !isNamespaceOrTranslationUnitScope(InnermostFileScope))
            InnermostFileScope = InnermostFileScope->getParent();
          UDirs.visitScopeChain(Initial, InnermostFileScope);

          UDirs.done();

          VisitedUsingDirectives = true;
        }

        if (CppNamespaceLookup(*this, R, Context, Ctx, UDirs)) {
          R.resolveKind();
          return true;
        }

        continue;
      }

      // Perform qualified name lookup into this context.
      // FIXME: In some cases, we know that every name that could be found by
      // this qualified name lookup will also be on the identifier chain. For
      // example, inside a class without any base classes, we never need to
      // perform qualified lookup because all of the members are on top of the
      // identifier chain.
      if (LookupQualifiedName(R, Ctx, /*InUnqualifiedLookup=*/true))
        return true;
    }
  }
}

// Stop if we ran out of scopes.
// FIXME:  This really, really shouldn't be happening.
if (!S) return false;

// If we are looking for members, no need to look into global/namespace scope.
if (NameKind == LookupMemberName)
  return false;

// Collect UsingDirectiveDecls in all scopes, and recursively all
// nominated namespaces by those using-directives.
//
// FIXME: Cache this sorted list in Scope structure, and DeclContext, so we
// don't build it for each lookup!
if (!VisitedUsingDirectives) {
  UDirs.visitScopeChain(Initial, S);
  UDirs.done();
}

// If we're not performing redeclaration lookup, do not look for local
// extern declarations outside of a function scope.
if (!R.isForRedeclaration())
  FindLocals.restore();

// Lookup namespace scope, and global scope.
// Unqualified name lookup in C++ requires looking into scopes
// that aren't strictly lexical, and therefore we walk through the
// context as well as walking through the scopes.
for (; S; S = S->getParent()) {
  // Check whether the IdResolver has anything in this scope.
  bool Found = false;
  for (; I != IEnd && S->isDeclScope(*I); ++I) {
    if (NamedDecl *ND = R.getAcceptableDecl(*I)) {
      // We found something.  Look for anything else in our scope
      // with this same name and in an acceptable identifier
      // namespace, so that we can construct an overload set if we
      // need to.
      Found = true;
      R.addDecl(ND);
    }
  }

  if (Found && S->isTemplateParamScope()) {
    R.resolveKind();
    return true;
  }

  DeclContext *Ctx = S->getEntity();
  if (!Ctx && S->isTemplateParamScope() && OutsideOfTemplateParamDC &&
      S->getParent() && !S->getParent()->isTemplateParamScope()) {
    // We've just searched the last template parameter scope and
    // found nothing, so look into the contexts between the
    // lexical and semantic declaration contexts returned by
    // findOuterContext(). This implements the name lookup behavior
    // of C++ [temp.local]p8.
    Ctx = OutsideOfTemplateParamDC;
    OutsideOfTemplateParamDC = nullptr;
  }

  if (Ctx) {
    DeclContext *OuterCtx;
    bool SearchAfterTemplateScope;
    std::tie(OuterCtx, SearchAfterTemplateScope) = findOuterContext(S);
    if (SearchAfterTemplateScope)
      OutsideOfTemplateParamDC = OuterCtx;

    for (; Ctx && !Ctx->Equals(OuterCtx); Ctx = Ctx->getLookupParent()) {
      // We do not directly look into transparent contexts, since
      // those entities will be found in the nearest enclosing
      // non-transparent context.
      if (Ctx->isTransparentContext())
        continue;

      // If we have a context, and it's not a context stashed in the
      // template parameter scope for an out-of-line definition, also
      // look into that context.
      if (!(Found && S->isTemplateParamScope())) {
        assert(Ctx->isFileContext() &&(static_cast <bool> (Ctx->isFileContext() &&
 "We should have been looking only at file context here already."
) ? void (0) : __assert_fail ("Ctx->isFileContext() && \"We should have been looking only at file context here already.\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1319, __extension__ __PRETTY_FUNCTION__))
            "We should have been looking only at file context here already.")(static_cast <bool> (Ctx->isFileContext() &&
 "We should have been looking only at file context here already."
) ? void (0) : __assert_fail ("Ctx->isFileContext() && \"We should have been looking only at file context here already.\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1319, __extension__ __PRETTY_FUNCTION__));

        // Look into context considering using-directives.
        if (CppNamespaceLookup(*this, R, Context, Ctx, UDirs))
          Found = true;
      }

      if (Found) {
        R.resolveKind();
        return true;
      }

      if (R.isForRedeclaration() && !Ctx->isTransparentContext())
        return false;
    }
  }

  if (R.isForRedeclaration() && Ctx && !Ctx->isTransparentContext())
    return false;
}

return !R.empty();
1341}

1343void Sema::makeMergedDefinitionVisible(NamedDecl *ND) {
if (auto *M = getCurrentModule())
  Context.mergeDefinitionIntoModule(ND, M);
else
  // We're not building a module; just make the definition visible.
  ND->setVisibleDespiteOwningModule();

// If ND is a template declaration, make the template parameters
// visible too. They're not (necessarily) within a mergeable DeclContext.
if (auto *TD = dyn_cast<TemplateDecl>(ND))
  for (auto *Param : *TD->getTemplateParameters())
    makeMergedDefinitionVisible(Param);
1355}

1357/// Find the module in which the given declaration was defined.
1358static Module *getDefiningModule(Sema &S, Decl *Entity) {
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(Entity)) {
  // If this function was instantiated from a template, the defining module is
  // the module containing the pattern.
  if (FunctionDecl *Pattern = FD->getTemplateInstantiationPattern())
    Entity = Pattern;
} else if (CXXRecordDecl *RD = dyn_cast<CXXRecordDecl>(Entity)) {
  if (CXXRecordDecl *Pattern = RD->getTemplateInstantiationPattern())
    Entity = Pattern;
} else if (EnumDecl *ED = dyn_cast<EnumDecl>(Entity)) {
  if (auto *Pattern = ED->getTemplateInstantiationPattern())
    Entity = Pattern;
} else if (VarDecl *VD = dyn_cast<VarDecl>(Entity)) {
  if (VarDecl *Pattern = VD->getTemplateInstantiationPattern())
    Entity = Pattern;
}

// Walk up to the containing context. That might also have been instantiated
// from a template.
DeclContext *Context = Entity->getLexicalDeclContext();
if (Context->isFileContext())
  return S.getOwningModule(Entity);
return getDefiningModule(S, cast<Decl>(Context));
1381}

1383llvm::DenseSet<Module*> &Sema::getLookupModules() {
unsigned N = CodeSynthesisContexts.size();
for (unsigned I = CodeSynthesisContextLookupModules.size();
     I != N; ++I) {
  Module *M = getDefiningModule(*this, CodeSynthesisContexts[I].Entity);
  if (M && !LookupModulesCache.insert(M).second)
    M = nullptr;
  CodeSynthesisContextLookupModules.push_back(M);
}
return LookupModulesCache;
1393}

1395bool Sema::hasVisibleMergedDefinition(NamedDecl *Def) {
for (Module *Merged : Context.getModulesWithMergedDefinition(Def))
  if (isModuleVisible(Merged))
    return true;
return false;
1400}

1402bool Sema::hasMergedDefinitionInCurrentModule(NamedDecl *Def) {
// FIXME: When not in local visibility mode, we can't tell the difference
// between a declaration being visible because we merged a local copy of
// the same declaration into it, and it being visible because its owning
// module is visible.
if (Def->getModuleOwnershipKind() == Decl::ModuleOwnershipKind::Visible &&
    getLangOpts().ModulesLocalVisibility)
  return true;
for (Module *Merged : Context.getModulesWithMergedDefinition(Def))
  if (Merged->getTopLevelModuleName() == getLangOpts().CurrentModule)
    return true;
return false;
1414}

1416template<typename ParmDecl>
1417static bool
1418hasVisibleDefaultArgument(Sema &S, const ParmDecl *D,
                        llvm::SmallVectorImpl<Module *> *Modules) {
if (!D->hasDefaultArgument())
  return false;

while (D) {
  auto &DefaultArg = D->getDefaultArgStorage();
  if (!DefaultArg.isInherited() && S.isVisible(D))
    return true;

  if (!DefaultArg.isInherited() && Modules) {
    auto *NonConstD = const_cast<ParmDecl*>(D);
    Modules->push_back(S.getOwningModule(NonConstD));
    const auto &Merged = S.Context.getModulesWithMergedDefinition(NonConstD);
    Modules->insert(Modules->end(), Merged.begin(), Merged.end());
  }

  // If there was a previous default argument, maybe its parameter is visible.
  D = DefaultArg.getInheritedFrom();
}
return false;
1439}

1441bool Sema::hasVisibleDefaultArgument(const NamedDecl *D,
                                   llvm::SmallVectorImpl<Module *> *Modules) {
if (auto *P = dyn_cast<TemplateTypeParmDecl>(D))
  return ::hasVisibleDefaultArgument(*this, P, Modules);
if (auto *P = dyn_cast<NonTypeTemplateParmDecl>(D))
  return ::hasVisibleDefaultArgument(*this, P, Modules);
return ::hasVisibleDefaultArgument(*this, cast<TemplateTemplateParmDecl>(D),
                                   Modules);
1449}

1451template<typename Filter>
1452static bool hasVisibleDeclarationImpl(Sema &S, const NamedDecl *D,
                                    llvm::SmallVectorImpl<Module *> *Modules,
                                    Filter F) {
bool HasFilteredRedecls = false;

for (auto *Redecl : D->redecls()) {
  auto *R = cast<NamedDecl>(Redecl);
  if (!F(R))
    continue;

  if (S.isVisible(R))
    return true;

  HasFilteredRedecls = true;

  if (Modules) {
    Modules->push_back(R->getOwningModule());
    const auto &Merged = S.Context.getModulesWithMergedDefinition(R);
    Modules->insert(Modules->end(), Merged.begin(), Merged.end());
  }
}

// Only return false if there is at least one redecl that is not filtered out.
if (HasFilteredRedecls)
  return false;

return true;
1479}

1481bool Sema::hasVisibleExplicitSpecialization(
  const NamedDecl *D, llvm::SmallVectorImpl<Module *> *Modules) {
return hasVisibleDeclarationImpl(*this, D, Modules, [](const NamedDecl *D) {
  if (auto *RD = dyn_cast<CXXRecordDecl>(D))
    return RD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization;
  if (auto *FD = dyn_cast<FunctionDecl>(D))
    return FD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization;
  if (auto *VD = dyn_cast<VarDecl>(D))
    return VD->getTemplateSpecializationKind() == TSK_ExplicitSpecialization;
  llvm_unreachable("unknown explicit specialization kind")::llvm::llvm_unreachable_internal("unknown explicit specialization kind"
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1490);
});
1492}

1494bool Sema::hasVisibleMemberSpecialization(
  const NamedDecl *D, llvm::SmallVectorImpl<Module *> *Modules) {
assert(isa<CXXRecordDecl>(D->getDeclContext()) &&(static_cast <bool> (isa<CXXRecordDecl>(D->getDeclContext
()) && "not a member specialization") ? void (0) : __assert_fail
 ("isa<CXXRecordDecl>(D->getDeclContext()) && \"not a member specialization\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1497, __extension__ __PRETTY_FUNCTION__))
       "not a member specialization")(static_cast <bool> (isa<CXXRecordDecl>(D->getDeclContext
()) && "not a member specialization") ? void (0) : __assert_fail
 ("isa<CXXRecordDecl>(D->getDeclContext()) && \"not a member specialization\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1497, __extension__ __PRETTY_FUNCTION__));
return hasVisibleDeclarationImpl(*this, D, Modules, [](const NamedDecl *D) {
  // If the specialization is declared at namespace scope, then it's a member
  // specialization declaration. If it's lexically inside the class
  // definition then it was instantiated.
  //
  // FIXME: This is a hack. There should be a better way to determine this.
  // FIXME: What about MS-style explicit specializations declared within a
  //        class definition?
  return D->getLexicalDeclContext()->isFileContext();
});
1508}

1510/// Determine whether a declaration is visible to name lookup.
1511///
1512/// This routine determines whether the declaration D is visible in the current
1513/// lookup context, taking into account the current template instantiation
1514/// stack. During template instantiation, a declaration is visible if it is
1515/// visible from a module containing any entity on the template instantiation
1516/// path (by instantiating a template, you allow it to see the declarations that
1517/// your module can see, including those later on in your module).
1518bool LookupResult::isVisibleSlow(Sema &SemaRef, NamedDecl *D) {
assert(D->isHidden() && "should not call this: not in slow case")(static_cast <bool> (D->isHidden() && "should not call this: not in slow case"
) ? void (0) : __assert_fail ("D->isHidden() && \"should not call this: not in slow case\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1519, __extension__ __PRETTY_FUNCTION__));

Module *DeclModule = SemaRef.getOwningModule(D);
if (!DeclModule) {
  // A module-private declaration with no owning module means this is in the
  // global module in the C++ Modules TS. This is visible within the same
  // translation unit only.
  // FIXME: Don't assume that "same translation unit" means the same thing
  // as "not from an AST file".
  assert(D->isModulePrivate() && "hidden decl has no module")(static_cast <bool> (D->isModulePrivate() &&
 "hidden decl has no module") ? void (0) : __assert_fail ("D->isModulePrivate() && \"hidden decl has no module\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1528, __extension__ __PRETTY_FUNCTION__));
  if (!D->isFromASTFile() || SemaRef.hasMergedDefinitionInCurrentModule(D))
    return true;
} else {
  // If the owning module is visible, and the decl is not module private,
  // then the decl is visible too. (Module private is ignored within the same
  // top-level module.)
  if (D->isModulePrivate()
        ? DeclModule->getTopLevelModuleName() ==
                  SemaRef.getLangOpts().CurrentModule ||
          SemaRef.hasMergedDefinitionInCurrentModule(D)
        : SemaRef.isModuleVisible(DeclModule) ||
          SemaRef.hasVisibleMergedDefinition(D))
    return true;
}

// Determine whether a decl context is a file context for the purpose of
// visibility. This looks through some (export and linkage spec) transparent
// contexts, but not others (enums).
auto IsEffectivelyFileContext = [](const DeclContext *DC) {
  return DC->isFileContext() || isa<LinkageSpecDecl>(DC) ||
         isa<ExportDecl>(DC);
};

// If this declaration is not at namespace scope
// then it is visible if its lexical parent has a visible definition.
DeclContext *DC = D->getLexicalDeclContext();
if (DC && !IsEffectivelyFileContext(DC)) {
  // For a parameter, check whether our current template declaration's
  // lexical context is visible, not whether there's some other visible
  // definition of it, because parameters aren't "within" the definition.
  //
  // In C++ we need to check for a visible definition due to ODR merging,
  // and in C we must not because each declaration of a function gets its own
  // set of declarations for tags in prototype scope.
  bool VisibleWithinParent;
  if (D->isTemplateParameter() || isa<ParmVarDecl>(D) ||
      (isa<FunctionDecl>(DC) && !SemaRef.getLangOpts().CPlusPlus))
    VisibleWithinParent = isVisible(SemaRef, cast<NamedDecl>(DC));
  else if (D->isModulePrivate()) {
    // A module-private declaration is only visible if an enclosing lexical
    // parent was merged with another definition in the current module.
    VisibleWithinParent = false;
    do {
      if (SemaRef.hasMergedDefinitionInCurrentModule(cast<NamedDecl>(DC))) {
        VisibleWithinParent = true;
        break;
      }
      DC = DC->getLexicalParent();
    } while (!IsEffectivelyFileContext(DC));
  } else {
    VisibleWithinParent = SemaRef.hasVisibleDefinition(cast<NamedDecl>(DC));
  }

  if (VisibleWithinParent && SemaRef.CodeSynthesisContexts.empty() &&
      // FIXME: Do something better in this case.
      !SemaRef.getLangOpts().ModulesLocalVisibility) {
    // Cache the fact that this declaration is implicitly visible because
    // its parent has a visible definition.
    D->setVisibleDespiteOwningModule();
  }
  return VisibleWithinParent;
}

// FIXME: All uses of DeclModule below this point should also check merged
// modules.
if (!DeclModule)
  return false;

// Find the extra places where we need to look.
const auto &LookupModules = SemaRef.getLookupModules();
if (LookupModules.empty())
  return false;

// If our lookup set contains the decl's module, it's visible.
if (LookupModules.count(DeclModule))
  return true;

// If the declaration isn't exported, it's not visible in any other module.
if (D->isModulePrivate())
  return false;

// Check whether DeclModule is transitively exported to an import of
// the lookup set.
return std::any_of(LookupModules.begin(), LookupModules.end(),
                   [&](const Module *M) {
                     return M->isModuleVisible(DeclModule); });
1615}

1617bool Sema::isVisibleSlow(const NamedDecl *D) {
return LookupResult::isVisible(*this, const_cast<NamedDecl*>(D));
1619}

1621bool Sema::shouldLinkPossiblyHiddenDecl(LookupResult &R, const NamedDecl *New) {
// FIXME: If there are both visible and hidden declarations, we need to take
// into account whether redeclaration is possible. Example:
// 
// Non-imported module:
//   int f(T);        // #1
// Some TU:
//   static int f(U); // #2, not a redeclaration of #1
//   int f(T);        // #3, finds both, should link with #1 if T != U, but
//                    // with #2 if T == U; neither should be ambiguous.
for (auto *D : R) {
  if (isVisible(D))
    return true;
  assert(D->isExternallyDeclarable() &&(static_cast <bool> (D->isExternallyDeclarable() &&
 "should not have hidden, non-externally-declarable result here"
) ? void (0) : __assert_fail ("D->isExternallyDeclarable() && \"should not have hidden, non-externally-declarable result here\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1635, __extension__ __PRETTY_FUNCTION__))
         "should not have hidden, non-externally-declarable result here")(static_cast <bool> (D->isExternallyDeclarable() &&
 "should not have hidden, non-externally-declarable result here"
) ? void (0) : __assert_fail ("D->isExternallyDeclarable() && \"should not have hidden, non-externally-declarable result here\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1635, __extension__ __PRETTY_FUNCTION__));
}

// This function is called once "New" is essentially complete, but before a
// previous declaration is attached. We can't query the linkage of "New" in
// general, because attaching the previous declaration can change the
// linkage of New to match the previous declaration.
//
// However, because we've just determined that there is no *visible* prior
// declaration, we can compute the linkage here. There are two possibilities:
//
//  * This is not a redeclaration; it's safe to compute the linkage now.
//
//  * This is a redeclaration of a prior declaration that is externally
//    redeclarable. In that case, the linkage of the declaration is not
//    changed by attaching the prior declaration, because both are externally
//    declarable (and thus ExternalLinkage or VisibleNoLinkage).
//
// FIXME: This is subtle and fragile.
return New->isExternallyDeclarable();
1655}

1657/// Retrieve the visible declaration corresponding to D, if any.
1658///
1659/// This routine determines whether the declaration D is visible in the current
1660/// module, with the current imports. If not, it checks whether any
1661/// redeclaration of D is visible, and if so, returns that declaration.
1662///
1663/// \returns D, or a visible previous declaration of D, whichever is more recent
1664/// and visible. If no declaration of D is visible, returns null.
1665static NamedDecl *findAcceptableDecl(Sema &SemaRef, NamedDecl *D,
                                   unsigned IDNS) {
assert(!LookupResult::isVisible(SemaRef, D) && "not in slow case")(static_cast <bool> (!LookupResult::isVisible(SemaRef, D
) && "not in slow case") ? void (0) : __assert_fail (
"!LookupResult::isVisible(SemaRef, D) && \"not in slow case\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1667, __extension__ __PRETTY_FUNCTION__));

for (auto RD : D->redecls()) {
  // Don't bother with extra checks if we already know this one isn't visible.
  if (RD == D)
    continue;

  auto ND = cast<NamedDecl>(RD);
  // FIXME: This is wrong in the case where the previous declaration is not
  // visible in the same scope as D. This needs to be done much more
  // carefully.
  if (ND->isInIdentifierNamespace(IDNS) &&
      LookupResult::isVisible(SemaRef, ND))
    return ND;
}

return nullptr;
1684}

1686bool Sema::hasVisibleDeclarationSlow(const NamedDecl *D,
                                   llvm::SmallVectorImpl<Module *> *Modules) {
assert(!isVisible(D) && "not in slow case")(static_cast <bool> (!isVisible(D) && "not in slow case"
) ? void (0) : __assert_fail ("!isVisible(D) && \"not in slow case\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1688, __extension__ __PRETTY_FUNCTION__));
return hasVisibleDeclarationImpl(*this, D, Modules,
                                 [](const NamedDecl *) { return true; });
1691}

1693NamedDecl *LookupResult::getAcceptableDeclSlow(NamedDecl *D) const {
if (auto *ND = dyn_cast<NamespaceDecl>(D)) {
  // Namespaces are a bit of a special case: we expect there to be a lot of
  // redeclarations of some namespaces, all declarations of a namespace are
  // essentially interchangeable, all declarations are found by name lookup
  // if any is, and namespaces are never looked up during template
  // instantiation. So we benefit from caching the check in this case, and
  // it is correct to do so.
  auto *Key = ND->getCanonicalDecl();
  if (auto *Acceptable = getSema().VisibleNamespaceCache.lookup(Key))
    return Acceptable;
  auto *Acceptable = isVisible(getSema(), Key)
                         ? Key
                         : findAcceptableDecl(getSema(), Key, IDNS);
  if (Acceptable)
    getSema().VisibleNamespaceCache.insert(std::make_pair(Key, Acceptable));
  return Acceptable;
}

return findAcceptableDecl(getSema(), D, IDNS);
1713}

1715/// Perform unqualified name lookup starting from a given
1716/// scope.
1717///
1718/// Unqualified name lookup (C++ [basic.lookup.unqual], C99 6.2.1) is
1719/// used to find names within the current scope. For example, 'x' in
1720/// @code
1721/// int x;
1722/// int f() {
1723///   return x; // unqualified name look finds 'x' in the global scope
1724/// }
1725/// @endcode
1726///
1727/// Different lookup criteria can find different names. For example, a
1728/// particular scope can have both a struct and a function of the same
1729/// name, and each can be found by certain lookup criteria. For more
1730/// information about lookup criteria, see the documentation for the
1731/// class LookupCriteria.
1732///
1733/// @param S        The scope from which unqualified name lookup will
1734/// begin. If the lookup criteria permits, name lookup may also search
1735/// in the parent scopes.
1736///
1737/// @param [in,out] R Specifies the lookup to perform (e.g., the name to
1738/// look up and the lookup kind), and is updated with the results of lookup
1739/// including zero or more declarations and possibly additional information
1740/// used to diagnose ambiguities.
1741///
1742/// @returns \c true if lookup succeeded and false otherwise.
1743bool Sema::LookupName(LookupResult &R, Scope *S, bool AllowBuiltinCreation) {
DeclarationName Name = R.getLookupName();
if (!Name) return false;

LookupNameKind NameKind = R.getLookupKind();

if (!getLangOpts().CPlusPlus) {
  // Unqualified name lookup in C/Objective-C is purely lexical, so
  // search in the declarations attached to the name.
  if (NameKind == Sema::LookupRedeclarationWithLinkage) {
    // Find the nearest non-transparent declaration scope.
    while (!(S->getFlags() & Scope::DeclScope) ||
           (S->getEntity() && S->getEntity()->isTransparentContext()))
      S = S->getParent();
  }

  // When performing a scope lookup, we want to find local extern decls.
  FindLocalExternScope FindLocals(R);

  // Scan up the scope chain looking for a decl that matches this
  // identifier that is in the appropriate namespace.  This search
  // should not take long, as shadowing of names is uncommon, and
  // deep shadowing is extremely uncommon.
  bool LeftStartingScope = false;

  for (IdentifierResolver::iterator I = IdResolver.begin(Name),
                                 IEnd = IdResolver.end();
       I != IEnd; ++I)
    if (NamedDecl *D = R.getAcceptableDecl(*I)) {
      if (NameKind == LookupRedeclarationWithLinkage) {
        // Determine whether this (or a previous) declaration is
        // out-of-scope.
        if (!LeftStartingScope && !S->isDeclScope(*I))
          LeftStartingScope = true;

        // If we found something outside of our starting scope that
        // does not have linkage, skip it.
        if (LeftStartingScope && !((*I)->hasLinkage())) {
          R.setShadowed();
          continue;
        }
      }
      else if (NameKind == LookupObjCImplicitSelfParam &&
               !isa<ImplicitParamDecl>(*I))
        continue;

      R.addDecl(D);

      // Check whether there are any other declarations with the same name
      // and in the same scope.
      if (I != IEnd) {
        // Find the scope in which this declaration was declared (if it
        // actually exists in a Scope).
        while (S && !S->isDeclScope(D))
          S = S->getParent();
        
        // If the scope containing the declaration is the translation unit,
        // then we'll need to perform our checks based on the matching
        // DeclContexts rather than matching scopes.
        if (S && isNamespaceOrTranslationUnitScope(S))
          S = nullptr;

        // Compute the DeclContext, if we need it.
        DeclContext *DC = nullptr;
        if (!S)
          DC = (*I)->getDeclContext()->getRedeclContext();
          
        IdentifierResolver::iterator LastI = I;
        for (++LastI; LastI != IEnd; ++LastI) {
          if (S) {
            // Match based on scope.
            if (!S->isDeclScope(*LastI))
              break;
          } else {
            // Match based on DeclContext.
            DeclContext *LastDC 
              = (*LastI)->getDeclContext()->getRedeclContext();
            if (!LastDC->Equals(DC))
              break;
          }

          // If the declaration is in the right namespace and visible, add it.
          if (NamedDecl *LastD = R.getAcceptableDecl(*LastI))
            R.addDecl(LastD);
        }

        R.resolveKind();
      }

      return true;
    }
} else {
  // Perform C++ unqualified name lookup.
  if (CppLookupName(R, S))
    return true;
}

// If we didn't find a use of this identifier, and if the identifier
// corresponds to a compiler builtin, create the decl object for the builtin
// now, injecting it into translation unit scope, and return it.
if (AllowBuiltinCreation && LookupBuiltin(*this, R))
  return true;

// If we didn't find a use of this identifier, the ExternalSource 
// may be able to handle the situation. 
// Note: some lookup failures are expected!
// See e.g. R.isForRedeclaration().
return (ExternalSource && ExternalSource->LookupUnqualified(R, S));
1851}

1853/// Perform qualified name lookup in the namespaces nominated by
1854/// using directives by the given context.
1855///
1856/// C++98 [namespace.qual]p2:
1857///   Given X::m (where X is a user-declared namespace), or given \::m
1858///   (where X is the global namespace), let S be the set of all
1859///   declarations of m in X and in the transitive closure of all
1860///   namespaces nominated by using-directives in X and its used
1861///   namespaces, except that using-directives are ignored in any
1862///   namespace, including X, directly containing one or more
1863///   declarations of m. No namespace is searched more than once in
1864///   the lookup of a name. If S is the empty set, the program is
1865///   ill-formed. Otherwise, if S has exactly one member, or if the
1866///   context of the reference is a using-declaration
1867///   (namespace.udecl), S is the required set of declarations of
1868///   m. Otherwise if the use of m is not one that allows a unique
1869///   declaration to be chosen from S, the program is ill-formed.
1870///
1871/// C++98 [namespace.qual]p5:
1872///   During the lookup of a qualified namespace member name, if the
1873///   lookup finds more than one declaration of the member, and if one
1874///   declaration introduces a class name or enumeration name and the
1875///   other declarations either introduce the same object, the same
1876///   enumerator or a set of functions, the non-type name hides the
1877///   class or enumeration name if and only if the declarations are
1878///   from the same namespace; otherwise (the declarations are from
1879///   different namespaces), the program is ill-formed.
1880static bool LookupQualifiedNameInUsingDirectives(Sema &S, LookupResult &R,
                                               DeclContext *StartDC) {
assert(StartDC->isFileContext() && "start context is not a file context")(static_cast <bool> (StartDC->isFileContext() &&
 "start context is not a file context") ? void (0) : __assert_fail
 ("StartDC->isFileContext() && \"start context is not a file context\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1882, __extension__ __PRETTY_FUNCTION__));

// We have not yet looked into these namespaces, much less added
// their "using-children" to the queue.
SmallVector<NamespaceDecl*, 8> Queue;

// We have at least added all these contexts to the queue.
llvm::SmallPtrSet<DeclContext*, 8> Visited;
Visited.insert(StartDC);

// We have already looked into the initial namespace; seed the queue
// with its using-children.
for (auto *I : StartDC->using_directives()) {
  NamespaceDecl *ND = I->getNominatedNamespace()->getOriginalNamespace();
  if (S.isVisible(I) && Visited.insert(ND).second)
    Queue.push_back(ND);
}

// The easiest way to implement the restriction in [namespace.qual]p5
// is to check whether any of the individual results found a tag
// and, if so, to declare an ambiguity if the final result is not
// a tag.
bool FoundTag = false;
bool FoundNonTag = false;

LookupResult LocalR(LookupResult::Temporary, R);

bool Found = false;
while (!Queue.empty()) {
  NamespaceDecl *ND = Queue.pop_back_val();

  // We go through some convolutions here to avoid copying results
  // between LookupResults.
  bool UseLocal = !R.empty();
  LookupResult &DirectR = UseLocal ? LocalR : R;
  bool FoundDirect = LookupDirect(S, DirectR, ND);

  if (FoundDirect) {
    // First do any local hiding.
    DirectR.resolveKind();

    // If the local result is a tag, remember that.
    if (DirectR.isSingleTagDecl())
      FoundTag = true;
    else
      FoundNonTag = true;

    // Append the local results to the total results if necessary.
    if (UseLocal) {
      R.addAllDecls(LocalR);
      LocalR.clear();
    }
  }

  // If we find names in this namespace, ignore its using directives.
  if (FoundDirect) {
    Found = true;
    continue;
  }

  for (auto I : ND->using_directives()) {
    NamespaceDecl *Nom = I->getNominatedNamespace();
    if (S.isVisible(I) && Visited.insert(Nom).second)
      Queue.push_back(Nom);
  }
}

if (Found) {
  if (FoundTag && FoundNonTag)
    R.setAmbiguousQualifiedTagHiding();
  else
    R.resolveKind();
}

return Found;
1957}

1959/// Callback that looks for any member of a class with the given name.
1960static bool LookupAnyMember(const CXXBaseSpecifier *Specifier,
                          CXXBasePath &Path, DeclarationName Name) {
RecordDecl *BaseRecord = Specifier->getType()->getAs<RecordType>()->getDecl();

Path.Decls = BaseRecord->lookup(Name);
return !Path.Decls.empty();
1966}

1968/// Determine whether the given set of member declarations contains only
1969/// static members, nested types, and enumerators.
1970template<typename InputIterator>
1971static bool HasOnlyStaticMembers(InputIterator First, InputIterator Last) {
Decl *D = (*First)->getUnderlyingDecl();
if (isa<VarDecl>(D) || isa<TypeDecl>(D) || isa<EnumConstantDecl>(D))
  return true;

if (isa<CXXMethodDecl>(D)) {
  // Determine whether all of the methods are static.
  bool AllMethodsAreStatic = true;
  for(; First != Last; ++First) {
    D = (*First)->getUnderlyingDecl();

    if (!isa<CXXMethodDecl>(D)) {
      assert(isa<TagDecl>(D) && "Non-function must be a tag decl")(static_cast <bool> (isa<TagDecl>(D) && "Non-function must be a tag decl"
) ? void (0) : __assert_fail ("isa<TagDecl>(D) && \"Non-function must be a tag decl\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 1983, __extension__ __PRETTY_FUNCTION__));
      break;
    }

    if (!cast<CXXMethodDecl>(D)->isStatic()) {
      AllMethodsAreStatic = false;
      break;
    }
  }

  if (AllMethodsAreStatic)
    return true;
}

return false;
1998}

2000/// Perform qualified name lookup into a given context.
2001///
2002/// Qualified name lookup (C++ [basic.lookup.qual]) is used to find
2003/// names when the context of those names is explicit specified, e.g.,
2004/// "std::vector" or "x->member", or as part of unqualified name lookup.
2005///
2006/// Different lookup criteria can find different names. For example, a
2007/// particular scope can have both a struct and a function of the same
2008/// name, and each can be found by certain lookup criteria. For more
2009/// information about lookup criteria, see the documentation for the
2010/// class LookupCriteria.
2011///
2012/// \param R captures both the lookup criteria and any lookup results found.
2013///
2014/// \param LookupCtx The context in which qualified name lookup will
2015/// search. If the lookup criteria permits, name lookup may also search
2016/// in the parent contexts or (for C++ classes) base classes.
2017///
2018/// \param InUnqualifiedLookup true if this is qualified name lookup that
2019/// occurs as part of unqualified name lookup.
2020///
2021/// \returns true if lookup succeeded, false if it failed.
2022bool Sema::LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
                             bool InUnqualifiedLookup) {
assert(LookupCtx && "Sema::LookupQualifiedName requires a lookup context")(static_cast <bool> (LookupCtx && "Sema::LookupQualifiedName requires a lookup context"
) ? void (0) : __assert_fail ("LookupCtx && \"Sema::LookupQualifiedName requires a lookup context\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2024, __extension__ __PRETTY_FUNCTION__));

if (!R.getLookupName())
  return false;

// Make sure that the declaration context is complete.
assert((!isa<TagDecl>(LookupCtx) ||(static_cast <bool> ((!isa<TagDecl>(LookupCtx) ||
 LookupCtx->isDependentContext() || cast<TagDecl>(LookupCtx
)->isCompleteDefinition() || cast<TagDecl>(LookupCtx
)->isBeingDefined()) && "Declaration context must already be complete!"
) ? void (0) : __assert_fail ("(!isa<TagDecl>(LookupCtx) || LookupCtx->isDependentContext() || cast<TagDecl>(LookupCtx)->isCompleteDefinition() || cast<TagDecl>(LookupCtx)->isBeingDefined()) && \"Declaration context must already be complete!\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2034, __extension__ __PRETTY_FUNCTION__))
        LookupCtx->isDependentContext() ||(static_cast <bool> ((!isa<TagDecl>(LookupCtx) ||
 LookupCtx->isDependentContext() || cast<TagDecl>(LookupCtx
)->isCompleteDefinition() || cast<TagDecl>(LookupCtx
)->isBeingDefined()) && "Declaration context must already be complete!"
) ? void (0) : __assert_fail ("(!isa<TagDecl>(LookupCtx) || LookupCtx->isDependentContext() || cast<TagDecl>(LookupCtx)->isCompleteDefinition() || cast<TagDecl>(LookupCtx)->isBeingDefined()) && \"Declaration context must already be complete!\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2034, __extension__ __PRETTY_FUNCTION__))
        cast<TagDecl>(LookupCtx)->isCompleteDefinition() ||(static_cast <bool> ((!isa<TagDecl>(LookupCtx) ||
 LookupCtx->isDependentContext() || cast<TagDecl>(LookupCtx
)->isCompleteDefinition() || cast<TagDecl>(LookupCtx
)->isBeingDefined()) && "Declaration context must already be complete!"
) ? void (0) : __assert_fail ("(!isa<TagDecl>(LookupCtx) || LookupCtx->isDependentContext() || cast<TagDecl>(LookupCtx)->isCompleteDefinition() || cast<TagDecl>(LookupCtx)->isBeingDefined()) && \"Declaration context must already be complete!\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2034, __extension__ __PRETTY_FUNCTION__))
        cast<TagDecl>(LookupCtx)->isBeingDefined()) &&(static_cast <bool> ((!isa<TagDecl>(LookupCtx) ||
 LookupCtx->isDependentContext() || cast<TagDecl>(LookupCtx
)->isCompleteDefinition() || cast<TagDecl>(LookupCtx
)->isBeingDefined()) && "Declaration context must already be complete!"
) ? void (0) : __assert_fail ("(!isa<TagDecl>(LookupCtx) || LookupCtx->isDependentContext() || cast<TagDecl>(LookupCtx)->isCompleteDefinition() || cast<TagDecl>(LookupCtx)->isBeingDefined()) && \"Declaration context must already be complete!\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2034, __extension__ __PRETTY_FUNCTION__))
       "Declaration context must already be complete!")(static_cast <bool> ((!isa<TagDecl>(LookupCtx) ||
 LookupCtx->isDependentContext() || cast<TagDecl>(LookupCtx
)->isCompleteDefinition() || cast<TagDecl>(LookupCtx
)->isBeingDefined()) && "Declaration context must already be complete!"
) ? void (0) : __assert_fail ("(!isa<TagDecl>(LookupCtx) || LookupCtx->isDependentContext() || cast<TagDecl>(LookupCtx)->isCompleteDefinition() || cast<TagDecl>(LookupCtx)->isBeingDefined()) && \"Declaration context must already be complete!\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2034, __extension__ __PRETTY_FUNCTION__));

struct QualifiedLookupInScope {
  bool oldVal;
  DeclContext *Context;
  // Set flag in DeclContext informing debugger that we're looking for qualified name
  QualifiedLookupInScope(DeclContext *ctx) : Context(ctx) { 
    oldVal = ctx->setUseQualifiedLookup(); 
  }
  ~QualifiedLookupInScope() { 
    Context->setUseQualifiedLookup(oldVal); 
  }
} QL(LookupCtx);

if (LookupDirect(*this, R, LookupCtx)) {
  R.resolveKind();
  if (isa<CXXRecordDecl>(LookupCtx))
    R.setNamingClass(cast<CXXRecordDecl>(LookupCtx));
  return true;
}

// Don't descend into implied contexts for redeclarations.
// C++98 [namespace.qual]p6:
//   In a declaration for a namespace member in which the
//   declarator-id is a qualified-id, given that the qualified-id
//   for the namespace member has the form
//     nested-name-specifier unqualified-id
//   the unqualified-id shall name a member of the namespace
//   designated by the nested-name-specifier.
// See also [class.mfct]p5 and [class.static.data]p2.
if (R.isForRedeclaration())
  return false;

// If this is a namespace, look it up in the implied namespaces.
if (LookupCtx->isFileContext())
  return LookupQualifiedNameInUsingDirectives(*this, R, LookupCtx);

// If this isn't a C++ class, we aren't allowed to look into base
// classes, we're done.
CXXRecordDecl *LookupRec = dyn_cast<CXXRecordDecl>(LookupCtx);
if (!LookupRec || !LookupRec->getDefinition())
  return false;

// If we're performing qualified name lookup into a dependent class,
// then we are actually looking into a current instantiation. If we have any
// dependent base classes, then we either have to delay lookup until
// template instantiation time (at which point all bases will be available)
// or we have to fail.
if (!InUnqualifiedLookup && LookupRec->isDependentContext() &&
    LookupRec->hasAnyDependentBases()) {
  R.setNotFoundInCurrentInstantiation();
  return false;
}

// Perform lookup into our base classes.
CXXBasePaths Paths;
Paths.setOrigin(LookupRec);

// Look for this member in our base classes
bool (*BaseCallback)(const CXXBaseSpecifier *Specifier, CXXBasePath &Path,
                     DeclarationName Name) = nullptr;
switch (R.getLookupKind()) {
  case LookupObjCImplicitSelfParam:
  case LookupOrdinaryName:
  case LookupMemberName:
  case LookupRedeclarationWithLinkage:
  case LookupLocalFriendName:
    BaseCallback = &CXXRecordDecl::FindOrdinaryMember;
    break;

  case LookupTagName:
    BaseCallback = &CXXRecordDecl::FindTagMember;
    break;

  case LookupAnyName:
    BaseCallback = &LookupAnyMember;
    break;

  case LookupOMPReductionName:
    BaseCallback = &CXXRecordDecl::FindOMPReductionMember;
    break;

  case LookupUsingDeclName:
    // This lookup is for redeclarations only.

  case LookupOperatorName:
  case LookupNamespaceName:
  case LookupObjCProtocolName:
  case LookupLabel:
    // These lookups will never find a member in a C++ class (or base class).
    return false;

  case LookupNestedNameSpecifierName:
    BaseCallback = &CXXRecordDecl::FindNestedNameSpecifierMember;
    break;
}

DeclarationName Name = R.getLookupName();
if (!LookupRec->lookupInBases(
        [=](const CXXBaseSpecifier *Specifier, CXXBasePath &Path) {
          return BaseCallback(Specifier, Path, Name);
        },
        Paths))
  return false;

R.setNamingClass(LookupRec);

// C++ [class.member.lookup]p2:
//   [...] If the resulting set of declarations are not all from
//   sub-objects of the same type, or the set has a nonstatic member
//   and includes members from distinct sub-objects, there is an
//   ambiguity and the program is ill-formed. Otherwise that set is
//   the result of the lookup.
QualType SubobjectType;
int SubobjectNumber = 0;
AccessSpecifier SubobjectAccess = AS_none;

for (CXXBasePaths::paths_iterator Path = Paths.begin(), PathEnd = Paths.end();
     Path != PathEnd; ++Path) {
  const CXXBasePathElement &PathElement = Path->back();

  // Pick the best (i.e. most permissive i.e. numerically lowest) access
  // across all paths.
  SubobjectAccess = std::min(SubobjectAccess, Path->Access);

  // Determine whether we're looking at a distinct sub-object or not.
  if (SubobjectType.isNull()) {
    // This is the first subobject we've looked at. Record its type.
    SubobjectType = Context.getCanonicalType(PathElement.Base->getType());
    SubobjectNumber = PathElement.SubobjectNumber;
    continue;
  }

  if (SubobjectType
               != Context.getCanonicalType(PathElement.Base->getType())) {
    // We found members of the given name in two subobjects of
    // different types. If the declaration sets aren't the same, this
    // lookup is ambiguous.
    if (HasOnlyStaticMembers(Path->Decls.begin(), Path->Decls.end())) {
      CXXBasePaths::paths_iterator FirstPath = Paths.begin();
      DeclContext::lookup_iterator FirstD = FirstPath->Decls.begin();
      DeclContext::lookup_iterator CurrentD = Path->Decls.begin();

      while (FirstD != FirstPath->Decls.end() &&
             CurrentD != Path->Decls.end()) {
       if ((*FirstD)->getUnderlyingDecl()->getCanonicalDecl() !=
           (*CurrentD)->getUnderlyingDecl()->getCanonicalDecl())
         break;

        ++FirstD;
        ++CurrentD;
      }

      if (FirstD == FirstPath->Decls.end() &&
          CurrentD == Path->Decls.end())
        continue;
    }

    R.setAmbiguousBaseSubobjectTypes(Paths);
    return true;
  }

  if (SubobjectNumber != PathElement.SubobjectNumber) {
    // We have a different subobject of the same type.

    // C++ [class.member.lookup]p5:
    //   A static member, a nested type or an enumerator defined in
    //   a base class T can unambiguously be found even if an object
    //   has more than one base class subobject of type T.
    if (HasOnlyStaticMembers(Path->Decls.begin(), Path->Decls.end()))
      continue;

    // We have found a nonstatic member name in multiple, distinct
    // subobjects. Name lookup is ambiguous.
    R.setAmbiguousBaseSubobjects(Paths);
    return true;
  }
}

// Lookup in a base class succeeded; return these results.

for (auto *D : Paths.front().Decls) {
  AccessSpecifier AS = CXXRecordDecl::MergeAccess(SubobjectAccess,
                                                  D->getAccess());
  R.addDecl(D, AS);
}
R.resolveKind();
return true;
2222}

2224/// Performs qualified name lookup or special type of lookup for
2225/// "__super::" scope specifier.
2226///
2227/// This routine is a convenience overload meant to be called from contexts
2228/// that need to perform a qualified name lookup with an optional C++ scope
2229/// specifier that might require special kind of lookup.
2230///
2231/// \param R captures both the lookup criteria and any lookup results found.
2232///
2233/// \param LookupCtx The context in which qualified name lookup will
2234/// search.
2235///
2236/// \param SS An optional C++ scope-specifier.
2237///
2238/// \returns true if lookup succeeded, false if it failed.
2239bool Sema::LookupQualifiedName(LookupResult &R, DeclContext *LookupCtx,
                             CXXScopeSpec &SS) {
auto *NNS = SS.getScopeRep();
if (NNS && NNS->getKind() == NestedNameSpecifier::Super)
  return LookupInSuper(R, NNS->getAsRecordDecl());
else

  return LookupQualifiedName(R, LookupCtx);
2247}

2249/// Performs name lookup for a name that was parsed in the
2250/// source code, and may contain a C++ scope specifier.
2251///
2252/// This routine is a convenience routine meant to be called from
2253/// contexts that receive a name and an optional C++ scope specifier
2254/// (e.g., "N::M::x"). It will then perform either qualified or
2255/// unqualified name lookup (with LookupQualifiedName or LookupName,
2256/// respectively) on the given name and return those results. It will
2257/// perform a special type of lookup for "__super::" scope specifier.
2258///
2259/// @param S        The scope from which unqualified name lookup will
2260/// begin.
2261///
2262/// @param SS       An optional C++ scope-specifier, e.g., "::N::M".
2263///
2264/// @param EnteringContext Indicates whether we are going to enter the
2265/// context of the scope-specifier SS (if present).
2266///
2267/// @returns True if any decls were found (but possibly ambiguous)
2268bool Sema::LookupParsedName(LookupResult &R, Scope *S, CXXScopeSpec *SS,
                          bool AllowBuiltinCreation, bool EnteringContext) {
if (SS && SS->isInvalid()) {
  // When the scope specifier is invalid, don't even look for
  // anything.
  return false;
}

if (SS && SS->isSet()) {
  NestedNameSpecifier *NNS = SS->getScopeRep();
  if (NNS->getKind() == NestedNameSpecifier::Super)
    return LookupInSuper(R, NNS->getAsRecordDecl());

  if (DeclContext *DC = computeDeclContext(*SS, EnteringContext)) {
    // We have resolved the scope specifier to a particular declaration
    // contex, and will perform name lookup in that context.
    if (!DC->isDependentContext() && RequireCompleteDeclContext(*SS, DC))
      return false;

    R.setContextRange(SS->getRange());
    return LookupQualifiedName(R, DC);
  }

  // We could not resolve the scope specified to a specific declaration
  // context, which means that SS refers to an unknown specialization.
  // Name lookup can't find anything in this case.
  R.setNotFoundInCurrentInstantiation();
  R.setContextRange(SS->getRange());
  return false;
}

// Perform unqualified name lookup starting in the given scope.
return LookupName(R, S, AllowBuiltinCreation);
2301}

2303/// Perform qualified name lookup into all base classes of the given
2304/// class.
2305///
2306/// \param R captures both the lookup criteria and any lookup results found.
2307///
2308/// \param Class The context in which qualified name lookup will
2309/// search. Name lookup will search in all base classes merging the results.
2310///
2311/// @returns True if any decls were found (but possibly ambiguous)
2312bool Sema::LookupInSuper(LookupResult &R, CXXRecordDecl *Class) {
// The access-control rules we use here are essentially the rules for
// doing a lookup in Class that just magically skipped the direct
// members of Class itself.  That is, the naming class is Class, and the
// access includes the access of the base.
for (const auto &BaseSpec : Class->bases()) {
  CXXRecordDecl *RD = cast<CXXRecordDecl>(
      BaseSpec.getType()->castAs<RecordType>()->getDecl());
  LookupResult Result(*this, R.getLookupNameInfo(), R.getLookupKind());
  Result.setBaseObjectType(Context.getRecordType(Class));
  LookupQualifiedName(Result, RD);

  // Copy the lookup results into the target, merging the base's access into
  // the path access.
  for (auto I = Result.begin(), E = Result.end(); I != E; ++I) {
    R.addDecl(I.getDecl(),
              CXXRecordDecl::MergeAccess(BaseSpec.getAccessSpecifier(),
                                         I.getAccess()));
  }

  Result.suppressDiagnostics();
}

R.resolveKind();
R.setNamingClass(Class);

return !R.empty();
2339}

2341/// Produce a diagnostic describing the ambiguity that resulted
2342/// from name lookup.
2343///
2344/// \param Result The result of the ambiguous lookup to be diagnosed.
2345void Sema::DiagnoseAmbiguousLookup(LookupResult &Result) {
assert(Result.isAmbiguous() && "Lookup result must be ambiguous")(static_cast <bool> (Result.isAmbiguous() && "Lookup result must be ambiguous"
) ? void (0) : __assert_fail ("Result.isAmbiguous() && \"Lookup result must be ambiguous\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2346, __extension__ __PRETTY_FUNCTION__));

DeclarationName Name = Result.getLookupName();
SourceLocation NameLoc = Result.getNameLoc();
SourceRange LookupRange = Result.getContextRange();

switch (Result.getAmbiguityKind()) {
case LookupResult::AmbiguousBaseSubobjects: {
  CXXBasePaths *Paths = Result.getBasePaths();
  QualType SubobjectType = Paths->front().back().Base->getType();
  Diag(NameLoc, diag::err_ambiguous_member_multiple_subobjects)
    << Name << SubobjectType << getAmbiguousPathsDisplayString(*Paths)
    << LookupRange;

  DeclContext::lookup_iterator Found = Paths->front().Decls.begin();
  while (isa<CXXMethodDecl>(*Found) &&
         cast<CXXMethodDecl>(*Found)->isStatic())
    ++Found;

  Diag((*Found)->getLocation(), diag::note_ambiguous_member_found);
  break;
}

case LookupResult::AmbiguousBaseSubobjectTypes: {
  Diag(NameLoc, diag::err_ambiguous_member_multiple_subobject_types)
    << Name << LookupRange;

  CXXBasePaths *Paths = Result.getBasePaths();
  std::set<Decl *> DeclsPrinted;
  for (CXXBasePaths::paths_iterator Path = Paths->begin(),
                                    PathEnd = Paths->end();
       Path != PathEnd; ++Path) {
    Decl *D = Path->Decls.front();
    if (DeclsPrinted.insert(D).second)
      Diag(D->getLocation(), diag::note_ambiguous_member_found);
  }
  break;
}

case LookupResult::AmbiguousTagHiding: {
  Diag(NameLoc, diag::err_ambiguous_tag_hiding) << Name << LookupRange;

  llvm::SmallPtrSet<NamedDecl*, 8> TagDecls;

  for (auto *D : Result)
    if (TagDecl *TD = dyn_cast<TagDecl>(D)) {
      TagDecls.insert(TD);
      Diag(TD->getLocation(), diag::note_hidden_tag);
    }

  for (auto *D : Result)
    if (!isa<TagDecl>(D))
      Diag(D->getLocation(), diag::note_hiding_object);

  // For recovery purposes, go ahead and implement the hiding.
  LookupResult::Filter F = Result.makeFilter();
  while (F.hasNext()) {
    if (TagDecls.count(F.next()))
      F.erase();
  }
  F.done();
  break;
}

case LookupResult::AmbiguousReference: {
  Diag(NameLoc, diag::err_ambiguous_reference) << Name << LookupRange;

  for (auto *D : Result)
    Diag(D->getLocation(), diag::note_ambiguous_candidate) << D;
  break;
}
}
2418}

2420namespace {
struct AssociatedLookup {
  AssociatedLookup(Sema &S, SourceLocation InstantiationLoc,
                   Sema::AssociatedNamespaceSet &Namespaces,
                   Sema::AssociatedClassSet &Classes)
    : S(S), Namespaces(Namespaces), Classes(Classes),
      InstantiationLoc(InstantiationLoc) {
  }

  Sema &S;
  Sema::AssociatedNamespaceSet &Namespaces;
  Sema::AssociatedClassSet &Classes;
  SourceLocation InstantiationLoc;
};
2434} // end anonymous namespace

2436static void
2437addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType T);

2439static void CollectEnclosingNamespace(Sema::AssociatedNamespaceSet &Namespaces,
                                    DeclContext *Ctx) {
// Add the associated namespace for this class.

// We don't use DeclContext::getEnclosingNamespaceContext() as this may
// be a locally scoped record.

// We skip out of inline namespaces. The innermost non-inline namespace
// contains all names of all its nested inline namespaces anyway, so we can
// replace the entire inline namespace tree with its root.
while (Ctx->isRecord() || Ctx->isTransparentContext() ||
       Ctx->isInlineNamespace())
  Ctx = Ctx->getParent();

if (Ctx->isFileContext())
  Namespaces.insert(Ctx->getPrimaryContext());
2455}

2457// Add the associated classes and namespaces for argument-dependent
2458// lookup that involves a template argument (C++ [basic.lookup.koenig]p2).
2459static void
2460addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
                                const TemplateArgument &Arg) {
// C++ [basic.lookup.koenig]p2, last bullet:
//   -- [...] ;
switch (Arg.getKind()) {
  case TemplateArgument::Null:
    break;

  case TemplateArgument::Type:
    // [...] the namespaces and classes associated with the types of the
    // template arguments provided for template type parameters (excluding
    // template template parameters)
    addAssociatedClassesAndNamespaces(Result, Arg.getAsType());
    break;

  case TemplateArgument::Template:
  case TemplateArgument::TemplateExpansion: {
    // [...] the namespaces in which any template template arguments are
    // defined; and the classes in which any member templates used as
    // template template arguments are defined.
    TemplateName Template = Arg.getAsTemplateOrTemplatePattern();
    if (ClassTemplateDecl *ClassTemplate
               = dyn_cast<ClassTemplateDecl>(Template.getAsTemplateDecl())) {
      DeclContext *Ctx = ClassTemplate->getDeclContext();
      if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
        Result.Classes.insert(EnclosingClass);
      // Add the associated namespace for this class.
      CollectEnclosingNamespace(Result.Namespaces, Ctx);
    }
    break;
  }

  case TemplateArgument::Declaration:
  case TemplateArgument::Integral:
  case TemplateArgument::Expression:
  case TemplateArgument::NullPtr:
    // [Note: non-type template arguments do not contribute to the set of
    //  associated namespaces. ]
    break;

  case TemplateArgument::Pack:
    for (const auto &P : Arg.pack_elements())
      addAssociatedClassesAndNamespaces(Result, P);
    break;
}
2505}

2507// Add the associated classes and namespaces for
2508// argument-dependent lookup with an argument of class type
2509// (C++ [basic.lookup.koenig]p2).
2510static void
2511addAssociatedClassesAndNamespaces(AssociatedLookup &Result,
                                CXXRecordDecl *Class) {

// Just silently ignore anything whose name is __va_list_tag.
if (Class->getDeclName() == Result.S.VAListTagName)
  return;

// C++ [basic.lookup.koenig]p2:
//   [...]
//     -- If T is a class type (including unions), its associated
//        classes are: the class itself; the class of which it is a
//        member, if any; and its direct and indirect base
//        classes. Its associated namespaces are the namespaces in
//        which its associated classes are defined.

// Add the class of which it is a member, if any.
DeclContext *Ctx = Class->getDeclContext();
if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
  Result.Classes.insert(EnclosingClass);
// Add the associated namespace for this class.
CollectEnclosingNamespace(Result.Namespaces, Ctx);

// Add the class itself. If we've already seen this class, we don't
// need to visit base classes.
//
// FIXME: That's not correct, we may have added this class only because it
// was the enclosing class of another class, and in that case we won't have
// added its base classes yet.
if (!Result.Classes.insert(Class))
  return;

// -- If T is a template-id, its associated namespaces and classes are
//    the namespace in which the template is defined; for member
//    templates, the member template's class; the namespaces and classes
//    associated with the types of the template arguments provided for
//    template type parameters (excluding template template parameters); the
//    namespaces in which any template template arguments are defined; and
//    the classes in which any member templates used as template template
//    arguments are defined. [Note: non-type template arguments do not
//    contribute to the set of associated namespaces. ]
if (ClassTemplateSpecializationDecl *Spec
      = dyn_cast<ClassTemplateSpecializationDecl>(Class)) {
  DeclContext *Ctx = Spec->getSpecializedTemplate()->getDeclContext();
  if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
    Result.Classes.insert(EnclosingClass);
  // Add the associated namespace for this class.
  CollectEnclosingNamespace(Result.Namespaces, Ctx);

  const TemplateArgumentList &TemplateArgs = Spec->getTemplateArgs();
  for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I)
    addAssociatedClassesAndNamespaces(Result, TemplateArgs[I]);
}

// Only recurse into base classes for complete types.
if (!Result.S.isCompleteType(Result.InstantiationLoc,
                             Result.S.Context.getRecordType(Class)))
  return;

// Add direct and indirect base classes along with their associated
// namespaces.
SmallVector<CXXRecordDecl *, 32> Bases;
Bases.push_back(Class);
while (!Bases.empty()) {
  // Pop this class off the stack.
  Class = Bases.pop_back_val();

  // Visit the base classes.
  for (const auto &Base : Class->bases()) {
    const RecordType *BaseType = Base.getType()->getAs<RecordType>();
    // In dependent contexts, we do ADL twice, and the first time around,
    // the base type might be a dependent TemplateSpecializationType, or a
    // TemplateTypeParmType. If that happens, simply ignore it.
    // FIXME: If we want to support export, we probably need to add the
    // namespace of the template in a TemplateSpecializationType, or even
    // the classes and namespaces of known non-dependent arguments.
    if (!BaseType)
      continue;
    CXXRecordDecl *BaseDecl = cast<CXXRecordDecl>(BaseType->getDecl());
    if (Result.Classes.insert(BaseDecl)) {
      // Find the associated namespace for this base class.
      DeclContext *BaseCtx = BaseDecl->getDeclContext();
      CollectEnclosingNamespace(Result.Namespaces, BaseCtx);

      // Make sure we visit the bases of this base class.
      if (BaseDecl->bases_begin() != BaseDecl->bases_end())
        Bases.push_back(BaseDecl);
    }
  }
}
2600}

2602// Add the associated classes and namespaces for
2603// argument-dependent lookup with an argument of type T
2604// (C++ [basic.lookup.koenig]p2).
2605static void
2606addAssociatedClassesAndNamespaces(AssociatedLookup &Result, QualType Ty) {
// C++ [basic.lookup.koenig]p2:
//
//   For each argument type T in the function call, there is a set
//   of zero or more associated namespaces and a set of zero or more
//   associated classes to be considered. The sets of namespaces and
//   classes is determined entirely by the types of the function
//   arguments (and the namespace of any template template
//   argument). Typedef names and using-declarations used to specify
//   the types do not contribute to this set. The sets of namespaces
//   and classes are determined in the following way:

SmallVector<const Type *, 16> Queue;
const Type *T = Ty->getCanonicalTypeInternal().getTypePtr();

while (true) {
  switch (T->getTypeClass()) {

2624#define TYPE(Class, Base)
2625#define DEPENDENT_TYPE(Class, Base) case Type::Class:
2626#define NON_CANONICAL_TYPE(Class, Base) case Type::Class:
2627#define NON_CANONICAL_UNLESS_DEPENDENT_TYPE(Class, Base) case Type::Class:
2628#define ABSTRACT_TYPE(Class, Base)
2629#include "clang/AST/TypeNodes.def"
    // T is canonical.  We can also ignore dependent types because
    // we don't need to do ADL at the definition point, but if we
    // wanted to implement template export (or if we find some other
    // use for associated classes and namespaces...) this would be
    // wrong.
    break;

  //    -- If T is a pointer to U or an array of U, its associated
  //       namespaces and classes are those associated with U.
  case Type::Pointer:
    T = cast<PointerType>(T)->getPointeeType().getTypePtr();
    continue;
  case Type::ConstantArray:
  case Type::IncompleteArray:
  case Type::VariableArray:
    T = cast<ArrayType>(T)->getElementType().getTypePtr();
    continue;

  //     -- If T is a fundamental type, its associated sets of
  //        namespaces and classes are both empty.
  case Type::Builtin:
    break;

  //     -- If T is a class type (including unions), its associated
  //        classes are: the class itself; the class of which it is a
  //        member, if any; and its direct and indirect base
  //        classes. Its associated namespaces are the namespaces in
  //        which its associated classes are defined.
  case Type::Record: {
    CXXRecordDecl *Class =
        cast<CXXRecordDecl>(cast<RecordType>(T)->getDecl());
    addAssociatedClassesAndNamespaces(Result, Class);
    break;
  }

  //     -- If T is an enumeration type, its associated namespace is
  //        the namespace in which it is defined. If it is class
  //        member, its associated class is the member's class; else
  //        it has no associated class.
  case Type::Enum: {
    EnumDecl *Enum = cast<EnumType>(T)->getDecl();

    DeclContext *Ctx = Enum->getDeclContext();
    if (CXXRecordDecl *EnclosingClass = dyn_cast<CXXRecordDecl>(Ctx))
      Result.Classes.insert(EnclosingClass);

    // Add the associated namespace for this class.
    CollectEnclosingNamespace(Result.Namespaces, Ctx);

    break;
  }

  //     -- If T is a function type, its associated namespaces and
  //        classes are those associated with the function parameter
  //        types and those associated with the return type.
  case Type::FunctionProto: {
    const FunctionProtoType *Proto = cast<FunctionProtoType>(T);
    for (const auto &Arg : Proto->param_types())
      Queue.push_back(Arg.getTypePtr());
    // fallthrough
    LLVM_FALLTHROUGH[[clang::fallthrough]];
  }
  case Type::FunctionNoProto: {
    const FunctionType *FnType = cast<FunctionType>(T);
    T = FnType->getReturnType().getTypePtr();
    continue;
  }

  //     -- If T is a pointer to a member function of a class X, its
  //        associated namespaces and classes are those associated
  //        with the function parameter types and return type,
  //        together with those associated with X.
  //
  //     -- If T is a pointer to a data member of class X, its
  //        associated namespaces and classes are those associated
  //        with the member type together with those associated with
  //        X.
  case Type::MemberPointer: {
    const MemberPointerType *MemberPtr = cast<MemberPointerType>(T);

    // Queue up the class type into which this points.
    Queue.push_back(MemberPtr->getClass());

    // And directly continue with the pointee type.
    T = MemberPtr->getPointeeType().getTypePtr();
    continue;
  }

  // As an extension, treat this like a normal pointer.
  case Type::BlockPointer:
    T = cast<BlockPointerType>(T)->getPointeeType().getTypePtr();
    continue;

  // References aren't covered by the standard, but that's such an
  // obvious defect that we cover them anyway.
  case Type::LValueReference:
  case Type::RValueReference:
    T = cast<ReferenceType>(T)->getPointeeType().getTypePtr();
    continue;

  // These are fundamental types.
  case Type::Vector:
  case Type::ExtVector:
  case Type::Complex:
    break;

  // Non-deduced auto types only get here for error cases.
  case Type::Auto:
  case Type::DeducedTemplateSpecialization:
    break;

  // If T is an Objective-C object or interface type, or a pointer to an 
  // object or interface type, the associated namespace is the global
  // namespace.
  case Type::ObjCObject:
  case Type::ObjCInterface:
  case Type::ObjCObjectPointer:
    Result.Namespaces.insert(Result.S.Context.getTranslationUnitDecl());
    break;

  // Atomic types are just wrappers; use the associations of the
  // contained type.
  case Type::Atomic:
    T = cast<AtomicType>(T)->getValueType().getTypePtr();
    continue;
  case Type::Pipe:
    T = cast<PipeType>(T)->getElementType().getTypePtr();
    continue;
  }

  if (Queue.empty())
    break;
  T = Queue.pop_back_val();
}
2764}

2766/// Find the associated classes and namespaces for
2767/// argument-dependent lookup for a call with the given set of
2768/// arguments.
2769///
2770/// This routine computes the sets of associated classes and associated
2771/// namespaces searched by argument-dependent lookup
2772/// (C++ [basic.lookup.argdep]) for a given set of arguments.
2773void Sema::FindAssociatedClassesAndNamespaces(
  SourceLocation InstantiationLoc, ArrayRef<Expr *> Args,
  AssociatedNamespaceSet &AssociatedNamespaces,
  AssociatedClassSet &AssociatedClasses) {
AssociatedNamespaces.clear();
AssociatedClasses.clear();

AssociatedLookup Result(*this, InstantiationLoc,
                        AssociatedNamespaces, AssociatedClasses);

// C++ [basic.lookup.koenig]p2:
//   For each argument type T in the function call, there is a set
//   of zero or more associated namespaces and a set of zero or more
//   associated classes to be considered. The sets of namespaces and
//   classes is determined entirely by the types of the function
//   arguments (and the namespace of any template template
//   argument).
for (unsigned ArgIdx = 0; ArgIdx != Args.size(); ++ArgIdx) {
  Expr *Arg = Args[ArgIdx];

  if (Arg->getType() != Context.OverloadTy) {
    addAssociatedClassesAndNamespaces(Result, Arg->getType());
    continue;
  }

  // [...] In addition, if the argument is the name or address of a
  // set of overloaded functions and/or function templates, its
  // associated classes and namespaces are the union of those
  // associated with each of the members of the set: the namespace
  // in which the function or function template is defined and the
  // classes and namespaces associated with its (non-dependent)
  // parameter types and return type.
  Arg = Arg->IgnoreParens();
  if (UnaryOperator *unaryOp = dyn_cast<UnaryOperator>(Arg))
    if (unaryOp->getOpcode() == UO_AddrOf)
      Arg = unaryOp->getSubExpr();

  UnresolvedLookupExpr *ULE = dyn_cast<UnresolvedLookupExpr>(Arg);
  if (!ULE) continue;

  for (const auto *D : ULE->decls()) {
    // Look through any using declarations to find the underlying function.
    const FunctionDecl *FDecl = D->getUnderlyingDecl()->getAsFunction();

    // Add the classes and namespaces associated with the parameter
    // types and return type of this function.
    addAssociatedClassesAndNamespaces(Result, FDecl->getType());
  }
}
2822}

2824NamedDecl *Sema::LookupSingleName(Scope *S, DeclarationName Name,
                                SourceLocation Loc,
                                LookupNameKind NameKind,
                                RedeclarationKind Redecl) {
LookupResult R(*this, Name, Loc, NameKind, Redecl);
LookupName(R, S);
return R.getAsSingle<NamedDecl>();
2831}

2833/// Find the protocol with the given name, if any.
2834ObjCProtocolDecl *Sema::LookupProtocol(IdentifierInfo *II,
                                     SourceLocation IdLoc,
                                     RedeclarationKind Redecl) {
Decl *D = LookupSingleName(TUScope, II, IdLoc,
                           LookupObjCProtocolName, Redecl);
return cast_or_null<ObjCProtocolDecl>(D);
2840}

2842void Sema::LookupOverloadedOperatorName(OverloadedOperatorKind Op, Scope *S,
                                      QualType T1, QualType T2,
                                      UnresolvedSetImpl &Functions) {
// C++ [over.match.oper]p3:
//     -- The set of non-member candidates is the result of the
//        unqualified lookup of operator@ in the context of the
//        expression according to the usual rules for name lookup in
//        unqualified function calls (3.4.2) except that all member
//        functions are ignored.
DeclarationName OpName = Context.DeclarationNames.getCXXOperatorName(Op);
LookupResult Operators(*this, OpName, SourceLocation(), LookupOperatorName);
LookupName(Operators, S);

assert(!Operators.isAmbiguous() && "Operator lookup cannot be ambiguous")(static_cast <bool> (!Operators.isAmbiguous() &&
 "Operator lookup cannot be ambiguous") ? void (0) : __assert_fail
 ("!Operators.isAmbiguous() && \"Operator lookup cannot be ambiguous\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2855, __extension__ __PRETTY_FUNCTION__));
Functions.append(Operators.begin(), Operators.end());
2857}

2859Sema::SpecialMemberOverloadResult Sema::LookupSpecialMember(CXXRecordDecl *RD,
                                                         CXXSpecialMember SM,
                                                         bool ConstArg,
                                                         bool VolatileArg,
                                                         bool RValueThis,
                                                         bool ConstThis,
                                                         bool VolatileThis) {
assert(CanDeclareSpecialMemberFunction(RD) &&(static_cast <bool> (CanDeclareSpecialMemberFunction(RD
) && "doing special member lookup into record that isn't fully complete"
) ? void (0) : __assert_fail ("CanDeclareSpecialMemberFunction(RD) && \"doing special member lookup into record that isn't fully complete\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2867, __extension__ __PRETTY_FUNCTION__))
       "doing special member lookup into record that isn't fully complete")(static_cast <bool> (CanDeclareSpecialMemberFunction(RD
) && "doing special member lookup into record that isn't fully complete"
) ? void (0) : __assert_fail ("CanDeclareSpecialMemberFunction(RD) && \"doing special member lookup into record that isn't fully complete\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2867, __extension__ __PRETTY_FUNCTION__));
RD = RD->getDefinition();
if (RValueThis || ConstThis || VolatileThis)
  assert((SM == CXXCopyAssignment || SM == CXXMoveAssignment) &&(static_cast <bool> ((SM == CXXCopyAssignment || SM == CXXMoveAssignment
) && "constructors and destructors always have unqualified lvalue this"
) ? void (0) : __assert_fail ("(SM == CXXCopyAssignment || SM == CXXMoveAssignment) && \"constructors and destructors always have unqualified lvalue this\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2871, __extension__ __PRETTY_FUNCTION__))
         "constructors and destructors always have unqualified lvalue this")(static_cast <bool> ((SM == CXXCopyAssignment || SM == CXXMoveAssignment
) && "constructors and destructors always have unqualified lvalue this"
) ? void (0) : __assert_fail ("(SM == CXXCopyAssignment || SM == CXXMoveAssignment) && \"constructors and destructors always have unqualified lvalue this\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2871, __extension__ __PRETTY_FUNCTION__));
if (ConstArg || VolatileArg)
  assert((SM != CXXDefaultConstructor && SM != CXXDestructor) &&(static_cast <bool> ((SM != CXXDefaultConstructor &&
 SM != CXXDestructor) && "parameter-less special members can't have qualified arguments"
) ? void (0) : __assert_fail ("(SM != CXXDefaultConstructor && SM != CXXDestructor) && \"parameter-less special members can't have qualified arguments\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2874, __extension__ __PRETTY_FUNCTION__))
         "parameter-less special members can't have qualified arguments")(static_cast <bool> ((SM != CXXDefaultConstructor &&
 SM != CXXDestructor) && "parameter-less special members can't have qualified arguments"
) ? void (0) : __assert_fail ("(SM != CXXDefaultConstructor && SM != CXXDestructor) && \"parameter-less special members can't have qualified arguments\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2874, __extension__ __PRETTY_FUNCTION__));

// FIXME: Get the caller to pass in a location for the lookup.
SourceLocation LookupLoc = RD->getLocation();

llvm::FoldingSetNodeID ID;
ID.AddPointer(RD);
ID.AddInteger(SM);
ID.AddInteger(ConstArg);
ID.AddInteger(VolatileArg);
ID.AddInteger(RValueThis);
ID.AddInteger(ConstThis);
ID.AddInteger(VolatileThis);

void *InsertPoint;
SpecialMemberOverloadResultEntry *Result =
  SpecialMemberCache.FindNodeOrInsertPos(ID, InsertPoint);

// This was already cached
if (Result)
  return *Result;

Result = BumpAlloc.Allocate<SpecialMemberOverloadResultEntry>();
Result = new (Result) SpecialMemberOverloadResultEntry(ID);
SpecialMemberCache.InsertNode(Result, InsertPoint);

if (SM == CXXDestructor) {
  if (RD->needsImplicitDestructor())
    DeclareImplicitDestructor(RD);
  CXXDestructorDecl *DD = RD->getDestructor();
  assert(DD && "record without a destructor")(static_cast <bool> (DD && "record without a destructor"
) ? void (0) : __assert_fail ("DD && \"record without a destructor\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2904, __extension__ __PRETTY_FUNCTION__));
  Result->setMethod(DD);
  Result->setKind(DD->isDeleted() ?
                  SpecialMemberOverloadResult::NoMemberOrDeleted :
                  SpecialMemberOverloadResult::Success);
  return *Result;
}

// Prepare for overload resolution. Here we construct a synthetic argument
// if necessary and make sure that implicit functions are declared.
CanQualType CanTy = Context.getCanonicalType(Context.getTagDeclType(RD));
DeclarationName Name;
Expr *Arg = nullptr;
unsigned NumArgs;

QualType ArgType = CanTy;
ExprValueKind VK = VK_LValue;

if (SM == CXXDefaultConstructor) {
  Name = Context.DeclarationNames.getCXXConstructorName(CanTy);
  NumArgs = 0;
  if (RD->needsImplicitDefaultConstructor())
    DeclareImplicitDefaultConstructor(RD);
} else {
  if (SM == CXXCopyConstructor || SM == CXXMoveConstructor) {
    Name = Context.DeclarationNames.getCXXConstructorName(CanTy);
    if (RD->needsImplicitCopyConstructor())
      DeclareImplicitCopyConstructor(RD);
    if (getLangOpts().CPlusPlus11 && RD->needsImplicitMoveConstructor())
      DeclareImplicitMoveConstructor(RD);
  } else {
    Name = Context.DeclarationNames.getCXXOperatorName(OO_Equal);
    if (RD->needsImplicitCopyAssignment())
      DeclareImplicitCopyAssignment(RD);
    if (getLangOpts().CPlusPlus11 && RD->needsImplicitMoveAssignment())
      DeclareImplicitMoveAssignment(RD);
  }

  if (ConstArg)
    ArgType.addConst();
  if (VolatileArg)
    ArgType.addVolatile();

  // This isn't /really/ specified by the standard, but it's implied
  // we should be working from an RValue in the case of move to ensure
  // that we prefer to bind to rvalue references, and an LValue in the
  // case of copy to ensure we don't bind to rvalue references.
  // Possibly an XValue is actually correct in the case of move, but
  // there is no semantic difference for class types in this restricted
  // case.
  if (SM == CXXCopyConstructor || SM == CXXCopyAssignment)
    VK = VK_LValue;
  else
    VK = VK_RValue;
}

OpaqueValueExpr FakeArg(LookupLoc, ArgType, VK);

if (SM != CXXDefaultConstructor) {
  NumArgs = 1;
  Arg = &FakeArg;
}

// Create the object argument
QualType ThisTy = CanTy;
if (ConstThis)
  ThisTy.addConst();
if (VolatileThis)
  ThisTy.addVolatile();
Expr::Classification Classification =
  OpaqueValueExpr(LookupLoc, ThisTy,
                  RValueThis ? VK_RValue : VK_LValue).Classify(Context);

// Now we perform lookup on the name we computed earlier and do overload
// resolution. Lookup is only performed directly into the class since there
// will always be a (possibly implicit) declaration to shadow any others.
OverloadCandidateSet OCS(LookupLoc, OverloadCandidateSet::CSK_Normal);
DeclContext::lookup_result R = RD->lookup(Name);

if (R.empty()) {
  // We might have no default constructor because we have a lambda's closure
  // type, rather than because there's some other declared constructor.
  // Every class has a copy/move constructor, copy/move assignment, and
  // destructor.
  assert(SM == CXXDefaultConstructor &&(static_cast <bool> (SM == CXXDefaultConstructor &&
 "lookup for a constructor or assignment operator was empty")
 ? void (0) : __assert_fail ("SM == CXXDefaultConstructor && \"lookup for a constructor or assignment operator was empty\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2989, __extension__ __PRETTY_FUNCTION__))
         "lookup for a constructor or assignment operator was empty")(static_cast <bool> (SM == CXXDefaultConstructor &&
 "lookup for a constructor or assignment operator was empty")
 ? void (0) : __assert_fail ("SM == CXXDefaultConstructor && \"lookup for a constructor or assignment operator was empty\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 2989, __extension__ __PRETTY_FUNCTION__));
  Result->setMethod(nullptr);
  Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
  return *Result;
}

// Copy the candidates as our processing of them may load new declarations
// from an external source and invalidate lookup_result.
SmallVector<NamedDecl *, 8> Candidates(R.begin(), R.end());

for (NamedDecl *CandDecl : Candidates) {
  if (CandDecl->isInvalidDecl())
    continue;

  DeclAccessPair Cand = DeclAccessPair::make(CandDecl, AS_public);
  auto CtorInfo = getConstructorInfo(Cand);
  if (CXXMethodDecl *M = dyn_cast<CXXMethodDecl>(Cand->getUnderlyingDecl())) {
    if (SM == CXXCopyAssignment || SM == CXXMoveAssignment)
      AddMethodCandidate(M, Cand, RD, ThisTy, Classification,
                         llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
    else if (CtorInfo)
      AddOverloadCandidate(CtorInfo.Constructor, CtorInfo.FoundDecl,
                           llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
    else
      AddOverloadCandidate(M, Cand, llvm::makeArrayRef(&Arg, NumArgs), OCS,
                           true);
  } else if (FunctionTemplateDecl *Tmpl =
               dyn_cast<FunctionTemplateDecl>(Cand->getUnderlyingDecl())) {
    if (SM == CXXCopyAssignment || SM == CXXMoveAssignment)
      AddMethodTemplateCandidate(
          Tmpl, Cand, RD, nullptr, ThisTy, Classification,
          llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
    else if (CtorInfo)
      AddTemplateOverloadCandidate(
          CtorInfo.ConstructorTmpl, CtorInfo.FoundDecl, nullptr,
          llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
    else
      AddTemplateOverloadCandidate(
          Tmpl, Cand, nullptr, llvm::makeArrayRef(&Arg, NumArgs), OCS, true);
  } else {
    assert(isa<UsingDecl>(Cand.getDecl()) &&(static_cast <bool> (isa<UsingDecl>(Cand.getDecl(
)) && "illegal Kind of operator = Decl") ? void (0) :
 __assert_fail ("isa<UsingDecl>(Cand.getDecl()) && \"illegal Kind of operator = Decl\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3030, __extension__ __PRETTY_FUNCTION__))
           "illegal Kind of operator = Decl")(static_cast <bool> (isa<UsingDecl>(Cand.getDecl(
)) && "illegal Kind of operator = Decl") ? void (0) :
 __assert_fail ("isa<UsingDecl>(Cand.getDecl()) && \"illegal Kind of operator = Decl\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3030, __extension__ __PRETTY_FUNCTION__));
  }
}

OverloadCandidateSet::iterator Best;
switch (OCS.BestViableFunction(*this, LookupLoc, Best)) {
  case OR_Success:
    Result->setMethod(cast<CXXMethodDecl>(Best->Function));
    Result->setKind(SpecialMemberOverloadResult::Success);
    break;

  case OR_Deleted:
    Result->setMethod(cast<CXXMethodDecl>(Best->Function));
    Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
    break;

  case OR_Ambiguous:
    Result->setMethod(nullptr);
    Result->setKind(SpecialMemberOverloadResult::Ambiguous);
    break;

  case OR_No_Viable_Function:
    Result->setMethod(nullptr);
    Result->setKind(SpecialMemberOverloadResult::NoMemberOrDeleted);
    break;
}

return *Result;
3058}

3060/// Look up the default constructor for the given class.
3061CXXConstructorDecl *Sema::LookupDefaultConstructor(CXXRecordDecl *Class) {
SpecialMemberOverloadResult Result =
  LookupSpecialMember(Class, CXXDefaultConstructor, false, false, false,
                      false, false);

return cast_or_null<CXXConstructorDecl>(Result.getMethod());
3067}

3069/// Look up the copying constructor for the given class.
3070CXXConstructorDecl *Sema::LookupCopyingConstructor(CXXRecordDecl *Class,
                                                 unsigned Quals) {
assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&(static_cast <bool> (!(Quals & ~(Qualifiers::Const |
 Qualifiers::Volatile)) && "non-const, non-volatile qualifiers for copy ctor arg"
) ? void (0) : __assert_fail ("!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) && \"non-const, non-volatile qualifiers for copy ctor arg\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3073, __extension__ __PRETTY_FUNCTION__))
       "non-const, non-volatile qualifiers for copy ctor arg")(static_cast <bool> (!(Quals & ~(Qualifiers::Const |
 Qualifiers::Volatile)) && "non-const, non-volatile qualifiers for copy ctor arg"
) ? void (0) : __assert_fail ("!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) && \"non-const, non-volatile qualifiers for copy ctor arg\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3073, __extension__ __PRETTY_FUNCTION__));
SpecialMemberOverloadResult Result =
  LookupSpecialMember(Class, CXXCopyConstructor, Quals & Qualifiers::Const,
                      Quals & Qualifiers::Volatile, false, false, false);

return cast_or_null<CXXConstructorDecl>(Result.getMethod());
3079}

3081/// Look up the moving constructor for the given class.
3082CXXConstructorDecl *Sema::LookupMovingConstructor(CXXRecordDecl *Class,
                                                unsigned Quals) {
SpecialMemberOverloadResult Result =
  LookupSpecialMember(Class, CXXMoveConstructor, Quals & Qualifiers::Const,
                      Quals & Qualifiers::Volatile, false, false, false);

return cast_or_null<CXXConstructorDecl>(Result.getMethod());
3089}

3091/// Look up the constructors for the given class.
3092DeclContext::lookup_result Sema::LookupConstructors(CXXRecordDecl *Class) {
// If the implicit constructors have not yet been declared, do so now.
if (CanDeclareSpecialMemberFunction(Class)) {
  if (Class->needsImplicitDefaultConstructor())
    DeclareImplicitDefaultConstructor(Class);
  if (Class->needsImplicitCopyConstructor())
    DeclareImplicitCopyConstructor(Class);
  if (getLangOpts().CPlusPlus11 && Class->needsImplicitMoveConstructor())
    DeclareImplicitMoveConstructor(Class);
}

CanQualType T = Context.getCanonicalType(Context.getTypeDeclType(Class));
DeclarationName Name = Context.DeclarationNames.getCXXConstructorName(T);
return Class->lookup(Name);
3106}

3108/// Look up the copying assignment operator for the given class.
3109CXXMethodDecl *Sema::LookupCopyingAssignment(CXXRecordDecl *Class,
                                           unsigned Quals, bool RValueThis,
                                           unsigned ThisQuals) {
assert(!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&(static_cast <bool> (!(Quals & ~(Qualifiers::Const |
 Qualifiers::Volatile)) && "non-const, non-volatile qualifiers for copy assignment arg"
) ? void (0) : __assert_fail ("!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) && \"non-const, non-volatile qualifiers for copy assignment arg\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3113, __extension__ __PRETTY_FUNCTION__))
       "non-const, non-volatile qualifiers for copy assignment arg")(static_cast <bool> (!(Quals & ~(Qualifiers::Const |
 Qualifiers::Volatile)) && "non-const, non-volatile qualifiers for copy assignment arg"
) ? void (0) : __assert_fail ("!(Quals & ~(Qualifiers::Const | Qualifiers::Volatile)) && \"non-const, non-volatile qualifiers for copy assignment arg\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3113, __extension__ __PRETTY_FUNCTION__));
assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&(static_cast <bool> (!(ThisQuals & ~(Qualifiers::Const
 | Qualifiers::Volatile)) && "non-const, non-volatile qualifiers for copy assignment this"
) ? void (0) : __assert_fail ("!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) && \"non-const, non-volatile qualifiers for copy assignment this\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3115, __extension__ __PRETTY_FUNCTION__))
       "non-const, non-volatile qualifiers for copy assignment this")(static_cast <bool> (!(ThisQuals & ~(Qualifiers::Const
 | Qualifiers::Volatile)) && "non-const, non-volatile qualifiers for copy assignment this"
) ? void (0) : __assert_fail ("!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) && \"non-const, non-volatile qualifiers for copy assignment this\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3115, __extension__ __PRETTY_FUNCTION__));
SpecialMemberOverloadResult Result =
  LookupSpecialMember(Class, CXXCopyAssignment, Quals & Qualifiers::Const,
                      Quals & Qualifiers::Volatile, RValueThis,
                      ThisQuals & Qualifiers::Const,
                      ThisQuals & Qualifiers::Volatile);

return Result.getMethod();
3123}

3125/// Look up the moving assignment operator for the given class.
3126CXXMethodDecl *Sema::LookupMovingAssignment(CXXRecordDecl *Class,
                                          unsigned Quals,
                                          bool RValueThis,
                                          unsigned ThisQuals) {
assert(!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) &&(static_cast <bool> (!(ThisQuals & ~(Qualifiers::Const
 | Qualifiers::Volatile)) && "non-const, non-volatile qualifiers for copy assignment this"
) ? void (0) : __assert_fail ("!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) && \"non-const, non-volatile qualifiers for copy assignment this\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3131, __extension__ __PRETTY_FUNCTION__))
       "non-const, non-volatile qualifiers for copy assignment this")(static_cast <bool> (!(ThisQuals & ~(Qualifiers::Const
 | Qualifiers::Volatile)) && "non-const, non-volatile qualifiers for copy assignment this"
) ? void (0) : __assert_fail ("!(ThisQuals & ~(Qualifiers::Const | Qualifiers::Volatile)) && \"non-const, non-volatile qualifiers for copy assignment this\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3131, __extension__ __PRETTY_FUNCTION__));
SpecialMemberOverloadResult Result =
  LookupSpecialMember(Class, CXXMoveAssignment, Quals & Qualifiers::Const,
                      Quals & Qualifiers::Volatile, RValueThis,
                      ThisQuals & Qualifiers::Const,
                      ThisQuals & Qualifiers::Volatile);

return Result.getMethod();
3139}

3141/// Look for the destructor of the given class.
3142///
3143/// During semantic analysis, this routine should be used in lieu of
3144/// CXXRecordDecl::getDestructor().
3145///
3146/// \returns The destructor for this class.
3147CXXDestructorDecl *Sema::LookupDestructor(CXXRecordDecl *Class) {
return cast<CXXDestructorDecl>(LookupSpecialMember(Class, CXXDestructor,
                                                   false, false, false,
                                                   false, false).getMethod());
3151}

3153/// LookupLiteralOperator - Determine which literal operator should be used for
3154/// a user-defined literal, per C++11 [lex.ext].
3155///
3156/// Normal overload resolution is not used to select which literal operator to
3157/// call for a user-defined literal. Look up the provided literal operator name,
3158/// and filter the results to the appropriate set for the given argument types.
3159Sema::LiteralOperatorLookupResult
3160Sema::LookupLiteralOperator(Scope *S, LookupResult &R,
                          ArrayRef<QualType> ArgTys,
                          bool AllowRaw, bool AllowTemplate,
                          bool AllowStringTemplate, bool DiagnoseMissing) {
LookupName(R, S);
assert(R.getResultKind() != LookupResult::Ambiguous &&(static_cast <bool> (R.getResultKind() != LookupResult::
Ambiguous && "literal operator lookup can't be ambiguous"
) ? void (0) : __assert_fail ("R.getResultKind() != LookupResult::Ambiguous && \"literal operator lookup can't be ambiguous\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3166, __extension__ __PRETTY_FUNCTION__))
       "literal operator lookup can't be ambiguous")(static_cast <bool> (R.getResultKind() != LookupResult::
Ambiguous && "literal operator lookup can't be ambiguous"
) ? void (0) : __assert_fail ("R.getResultKind() != LookupResult::Ambiguous && \"literal operator lookup can't be ambiguous\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3166, __extension__ __PRETTY_FUNCTION__));

// Filter the lookup results appropriately.
LookupResult::Filter F = R.makeFilter();

bool FoundRaw = false;
bool FoundTemplate = false;
bool FoundStringTemplate = false;
bool FoundExactMatch = false;

while (F.hasNext()) {
  Decl *D = F.next();
  if (UsingShadowDecl *USD = dyn_cast<UsingShadowDecl>(D))
    D = USD->getTargetDecl();

  // If the declaration we found is invalid, skip it.
  if (D->isInvalidDecl()) {
    F.erase();
    continue;
  }

  bool IsRaw = false;
  bool IsTemplate = false;
  bool IsStringTemplate = false;
  bool IsExactMatch = false;

  if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
    if (FD->getNumParams() == 1 &&
        FD->getParamDecl(0)->getType()->getAs<PointerType>())
      IsRaw = true;
    else if (FD->getNumParams() == ArgTys.size()) {
      IsExactMatch = true;
      for (unsigned ArgIdx = 0; ArgIdx != ArgTys.size(); ++ArgIdx) {
        QualType ParamTy = FD->getParamDecl(ArgIdx)->getType();
        if (!Context.hasSameUnqualifiedType(ArgTys[ArgIdx], ParamTy)) {
          IsExactMatch = false;
          break;
        }
      }
    }
  }
  if (FunctionTemplateDecl *FD = dyn_cast<FunctionTemplateDecl>(D)) {
    TemplateParameterList *Params = FD->getTemplateParameters();
    if (Params->size() == 1)
      IsTemplate = true;
    else
      IsStringTemplate = true;
  }

  if (IsExactMatch) {
    FoundExactMatch = true;
    AllowRaw = false;
    AllowTemplate = false;
    AllowStringTemplate = false;
    if (FoundRaw || FoundTemplate || FoundStringTemplate) {
      // Go through again and remove the raw and template decls we've
      // already found.
      F.restart();
      FoundRaw = FoundTemplate = FoundStringTemplate = false;
    }
  } else if (AllowRaw && IsRaw) {
    FoundRaw = true;
  } else if (AllowTemplate && IsTemplate) {
    FoundTemplate = true;
  } else if (AllowStringTemplate && IsStringTemplate) {
    FoundStringTemplate = true;
  } else {
    F.erase();
  }
}

F.done();

// C++11 [lex.ext]p3, p4: If S contains a literal operator with a matching
// parameter type, that is used in preference to a raw literal operator
// or literal operator template.
if (FoundExactMatch)
  return LOLR_Cooked;

// C++11 [lex.ext]p3, p4: S shall contain a raw literal operator or a literal
// operator template, but not both.
if (FoundRaw && FoundTemplate) {
  Diag(R.getNameLoc(), diag::err_ovl_ambiguous_call) << R.getLookupName();
  for (LookupResult::iterator I = R.begin(), E = R.end(); I != E; ++I)
    NoteOverloadCandidate(*I, (*I)->getUnderlyingDecl()->getAsFunction());
  return LOLR_Error;
}

if (FoundRaw)
  return LOLR_Raw;

if (FoundTemplate)
  return LOLR_Template;

if (FoundStringTemplate)
  return LOLR_StringTemplate;

// Didn't find anything we could use.
if (DiagnoseMissing) {
  Diag(R.getNameLoc(), diag::err_ovl_no_viable_literal_operator)
      << R.getLookupName() << (int)ArgTys.size() << ArgTys[0]
      << (ArgTys.size() == 2 ? ArgTys[1] : QualType()) << AllowRaw
      << (AllowTemplate || AllowStringTemplate);
  return LOLR_Error;
}

return LOLR_ErrorNoDiagnostic;
3273}

3275void ADLResult::insert(NamedDecl *New) {
NamedDecl *&Old = Decls[cast<NamedDecl>(New->getCanonicalDecl())];

// If we haven't yet seen a decl for this key, or the last decl
// was exactly this one, we're done.
if (Old == nullptr || Old == New) {
  Old = New;
  return;
}

// Otherwise, decide which is a more recent redeclaration.
FunctionDecl *OldFD = Old->getAsFunction();
FunctionDecl *NewFD = New->getAsFunction();

FunctionDecl *Cursor = NewFD;
while (true) {
  Cursor = Cursor->getPreviousDecl();

  // If we got to the end without finding OldFD, OldFD is the newer
  // declaration;  leave things as they are.
  if (!Cursor) return;

  // If we do find OldFD, then NewFD is newer.
  if (Cursor == OldFD) break;

  // Otherwise, keep looking.
}

Old = New;
3304}

3306void Sema::ArgumentDependentLookup(DeclarationName Name, SourceLocation Loc,
                                 ArrayRef<Expr *> Args, ADLResult &Result) {
// Find all of the associated namespaces and classes based on the
// arguments we have.
AssociatedNamespaceSet AssociatedNamespaces;
AssociatedClassSet AssociatedClasses;
FindAssociatedClassesAndNamespaces(Loc, Args,
                                   AssociatedNamespaces,
                                   AssociatedClasses);

// C++ [basic.lookup.argdep]p3:
//   Let X be the lookup set produced by unqualified lookup (3.4.1)
//   and let Y be the lookup set produced by argument dependent
//   lookup (defined as follows). If X contains [...] then Y is
//   empty. Otherwise Y is the set of declarations found in the
//   namespaces associated with the argument types as described
//   below. The set of declarations found by the lookup of the name
//   is the union of X and Y.
//
// Here, we compute Y and add its members to the overloaded
// candidate set.
for (auto *NS : AssociatedNamespaces) {
  //   When considering an associated namespace, the lookup is the
  //   same as the lookup performed when the associated namespace is
  //   used as a qualifier (3.4.3.2) except that:
  //
  //     -- Any using-directives in the associated namespace are
  //        ignored.
  //
  //     -- Any namespace-scope friend functions declared in
  //        associated classes are visible within their respective
  //        namespaces even if they are not visible during an ordinary
  //        lookup (11.4).
  DeclContext::lookup_result R = NS->lookup(Name);
  for (auto *D : R) {
    auto *Underlying = D;
    if (auto *USD = dyn_cast<UsingShadowDecl>(D))
      Underlying = USD->getTargetDecl();

    if (!isa<FunctionDecl>(Underlying) &&
        !isa<FunctionTemplateDecl>(Underlying))
      continue;

    if (!isVisible(D)) {
      D = findAcceptableDecl(
          *this, D, (Decl::IDNS_Ordinary | Decl::IDNS_OrdinaryFriend));
      if (!D)
        continue;
      if (auto *USD = dyn_cast<UsingShadowDecl>(D))
        Underlying = USD->getTargetDecl();
    }

    // If the only declaration here is an ordinary friend, consider
    // it only if it was declared in an associated classes.
    if ((D->getIdentifierNamespace() & Decl::IDNS_Ordinary) == 0) {
      // If it's neither ordinarily visible nor a friend, we can't find it.
      if ((D->getIdentifierNamespace() & Decl::IDNS_OrdinaryFriend) == 0)
        continue;

      bool DeclaredInAssociatedClass = false;
      for (Decl *DI = D; DI; DI = DI->getPreviousDecl()) {
        DeclContext *LexDC = DI->getLexicalDeclContext();
        if (isa<CXXRecordDecl>(LexDC) &&
            AssociatedClasses.count(cast<CXXRecordDecl>(LexDC)) &&
            isVisible(cast<NamedDecl>(DI))) {
          DeclaredInAssociatedClass = true;
          break;
        }
      }
      if (!DeclaredInAssociatedClass)
        continue;
    }

    // FIXME: Preserve D as the FoundDecl.
    Result.insert(Underlying);
  }
}
3383}

3385//----------------------------------------------------------------------------
3386// Search for all visible declarations.
3387//----------------------------------------------------------------------------
3388VisibleDeclConsumer::~VisibleDeclConsumer() { }

3390bool VisibleDeclConsumer::includeHiddenDecls() const { return false; }

3392namespace {

3394class ShadowContextRAII;

3396class VisibleDeclsRecord {
3397public:
/// An entry in the shadow map, which is optimized to store a
/// single declaration (the common case) but can also store a list
/// of declarations.
typedef llvm::TinyPtrVector<NamedDecl*> ShadowMapEntry;

3403private:
/// A mapping from declaration names to the declarations that have
/// this name within a particular scope.
typedef llvm::DenseMap<DeclarationName, ShadowMapEntry> ShadowMap;

/// A list of shadow maps, which is used to model name hiding.
std::list<ShadowMap> ShadowMaps;

/// The declaration contexts we have already visited.
llvm::SmallPtrSet<DeclContext *, 8> VisitedContexts;

friend class ShadowContextRAII;

3416public:
/// Determine whether we have already visited this context
/// (and, if not, note that we are going to visit that context now).
bool visitedContext(DeclContext *Ctx) {
  return !VisitedContexts.insert(Ctx).second;
}

bool alreadyVisitedContext(DeclContext *Ctx) {
  return VisitedContexts.count(Ctx);
}

/// Determine whether the given declaration is hidden in the
/// current scope.
///
/// \returns the declaration that hides the given declaration, or
/// NULL if no such declaration exists.
NamedDecl *checkHidden(NamedDecl *ND);

/// Add a declaration to the current shadow map.
void add(NamedDecl *ND) {
  ShadowMaps.back()[ND->getDeclName()].push_back(ND);
}
3438};

3440/// RAII object that records when we've entered a shadow context.
3441class ShadowContextRAII {
VisibleDeclsRecord &Visible;

typedef VisibleDeclsRecord::ShadowMap ShadowMap;

3446public:
ShadowContextRAII(VisibleDeclsRecord &Visible) : Visible(Visible) {
  Visible.ShadowMaps.emplace_back();
}

~ShadowContextRAII() {
  Visible.ShadowMaps.pop_back();
}
3454};

3456} // end anonymous namespace

3458NamedDecl *VisibleDeclsRecord::checkHidden(NamedDecl *ND) {
unsigned IDNS = ND->getIdentifierNamespace();
std::list<ShadowMap>::reverse_iterator SM = ShadowMaps.rbegin();
for (std::list<ShadowMap>::reverse_iterator SMEnd = ShadowMaps.rend();
     SM != SMEnd; ++SM) {
  ShadowMap::iterator Pos = SM->find(ND->getDeclName());
  if (Pos == SM->end())
    continue;

  for (auto *D : Pos->second) {
    // A tag declaration does not hide a non-tag declaration.
    if (D->hasTagIdentifierNamespace() &&
        (IDNS & (Decl::IDNS_Member | Decl::IDNS_Ordinary |
                 Decl::IDNS_ObjCProtocol)))
      continue;

    // Protocols are in distinct namespaces from everything else.
    if (((D->getIdentifierNamespace() & Decl::IDNS_ObjCProtocol)
         || (IDNS & Decl::IDNS_ObjCProtocol)) &&
        D->getIdentifierNamespace() != IDNS)
      continue;

    // Functions and function templates in the same scope overload
    // rather than hide.  FIXME: Look for hiding based on function
    // signatures!
    if (D->getUnderlyingDecl()->isFunctionOrFunctionTemplate() &&
        ND->getUnderlyingDecl()->isFunctionOrFunctionTemplate() &&
        SM == ShadowMaps.rbegin())
      continue;

    // A shadow declaration that's created by a resolved using declaration
    // is not hidden by the same using declaration.
    if (isa<UsingShadowDecl>(ND) && isa<UsingDecl>(D) &&
        cast<UsingShadowDecl>(ND)->getUsingDecl() == D)
      continue;

    // We've found a declaration that hides this one.
    return D;
  }
}

return nullptr;
3500}

3502static void LookupVisibleDecls(DeclContext *Ctx, LookupResult &Result,
                             bool QualifiedNameLookup,
                             bool InBaseClass,
                             VisibleDeclConsumer &Consumer,
                             VisibleDeclsRecord &Visited,
                             bool IncludeDependentBases,
                             bool LoadExternal) {
if (!Ctx)
  return;

// Make sure we don't visit the same context twice.
if (Visited.visitedContext(Ctx->getPrimaryContext()))
  return;

Consumer.EnteredContext(Ctx);

// Outside C++, lookup results for the TU live on identifiers.
if (isa<TranslationUnitDecl>(Ctx) &&
    !Result.getSema().getLangOpts().CPlusPlus) {
  auto &S = Result.getSema();
  auto &Idents = S.Context.Idents;

  // Ensure all external identifiers are in the identifier table.
  if (LoadExternal)
    if (IdentifierInfoLookup *External = Idents.getExternalIdentifierLookup()) {
      std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
      for (StringRef Name = Iter->Next(); !Name.empty(); Name = Iter->Next())
        Idents.get(Name);
    }

  // Walk all lookup results in the TU for each identifier.
  for (const auto &Ident : Idents) {
    for (auto I = S.IdResolver.begin(Ident.getValue()),
              E = S.IdResolver.end();
         I != E; ++I) {
      if (S.IdResolver.isDeclInScope(*I, Ctx)) {
        if (NamedDecl *ND = Result.getAcceptableDecl(*I)) {
          Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
          Visited.add(ND);
        }
      }
    }
  }

  return;
}

if (CXXRecordDecl *Class = dyn_cast<CXXRecordDecl>(Ctx))
  Result.getSema().ForceDeclarationOfImplicitMembers(Class);

// We sometimes skip loading namespace-level results (they tend to be huge).
bool Load = LoadExternal ||
            !(isa<TranslationUnitDecl>(Ctx) || isa<NamespaceDecl>(Ctx));
// Enumerate all of the results in this context.
for (DeclContextLookupResult R :
     Load ? Ctx->lookups()
          : Ctx->noload_lookups(/*PreserveInternalState=*/false)) {
  for (auto *D : R) {
    if (auto *ND = Result.getAcceptableDecl(D)) {
      Consumer.FoundDecl(ND, Visited.checkHidden(ND), Ctx, InBaseClass);
      Visited.add(ND);
    }
  }
}

// Traverse using directives for qualified name lookup.
if (QualifiedNameLookup) {
  ShadowContextRAII Shadow(Visited);
  for (auto I : Ctx->using_directives()) {
    if (!Result.getSema().isVisible(I))
      continue;
    LookupVisibleDecls(I->getNominatedNamespace(), Result,
                       QualifiedNameLookup, InBaseClass, Consumer, Visited,
                       IncludeDependentBases, LoadExternal);
  }
}

// Traverse the contexts of inherited C++ classes.
if (CXXRecordDecl *Record = dyn_cast<CXXRecordDecl>(Ctx)) {
  if (!Record->hasDefinition())
    return;

  for (const auto &B : Record->bases()) {
    QualType BaseType = B.getType();

    RecordDecl *RD;
    if (BaseType->isDependentType()) {
      if (!IncludeDependentBases) {
        // Don't look into dependent bases, because name lookup can't look
        // there anyway.
        continue;
      }
      const auto *TST = BaseType->getAs<TemplateSpecializationType>();
      if (!TST)
        continue;
      TemplateName TN = TST->getTemplateName();
      const auto *TD =
          dyn_cast_or_null<ClassTemplateDecl>(TN.getAsTemplateDecl());
      if (!TD)
        continue;
      RD = TD->getTemplatedDecl();
    } else {
      const auto *Record = BaseType->getAs<RecordType>();
      if (!Record)
        continue;
      RD = Record->getDecl();
    }

    // FIXME: It would be nice to be able to determine whether referencing
    // a particular member would be ambiguous. For example, given
    //
    //   struct A { int member; };
    //   struct B { int member; };
    //   struct C : A, B { };
    //
    //   void f(C *c) { c->### }
    //
    // accessing 'member' would result in an ambiguity. However, we
    // could be smart enough to qualify the member with the base
    // class, e.g.,
    //
    //   c->B::member
    //
    // or
    //
    //   c->A::member

    // Find results in this base class (and its bases).
    ShadowContextRAII Shadow(Visited);
    LookupVisibleDecls(RD, Result, QualifiedNameLookup, true, Consumer,
                       Visited, IncludeDependentBases, LoadExternal);
  }
}

// Traverse the contexts of Objective-C classes.
if (ObjCInterfaceDecl *IFace = dyn_cast<ObjCInterfaceDecl>(Ctx)) {
  // Traverse categories.
  for (auto *Cat : IFace->visible_categories()) {
    ShadowContextRAII Shadow(Visited);
    LookupVisibleDecls(Cat, Result, QualifiedNameLookup, false, Consumer,
                       Visited, IncludeDependentBases, LoadExternal);
  }

  // Traverse protocols.
  for (auto *I : IFace->all_referenced_protocols()) {
    ShadowContextRAII Shadow(Visited);
    LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
                       Visited, IncludeDependentBases, LoadExternal);
  }

  // Traverse the superclass.
  if (IFace->getSuperClass()) {
    ShadowContextRAII Shadow(Visited);
    LookupVisibleDecls(IFace->getSuperClass(), Result, QualifiedNameLookup,
                       true, Consumer, Visited, IncludeDependentBases,
                       LoadExternal);
  }

  // If there is an implementation, traverse it. We do this to find
  // synthesized ivars.
  if (IFace->getImplementation()) {
    ShadowContextRAII Shadow(Visited);
    LookupVisibleDecls(IFace->getImplementation(), Result,
                       QualifiedNameLookup, InBaseClass, Consumer, Visited,
                       IncludeDependentBases, LoadExternal);
  }
} else if (ObjCProtocolDecl *Protocol = dyn_cast<ObjCProtocolDecl>(Ctx)) {
  for (auto *I : Protocol->protocols()) {
    ShadowContextRAII Shadow(Visited);
    LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
                       Visited, IncludeDependentBases, LoadExternal);
  }
} else if (ObjCCategoryDecl *Category = dyn_cast<ObjCCategoryDecl>(Ctx)) {
  for (auto *I : Category->protocols()) {
    ShadowContextRAII Shadow(Visited);
    LookupVisibleDecls(I, Result, QualifiedNameLookup, false, Consumer,
                       Visited, IncludeDependentBases, LoadExternal);
  }

  // If there is an implementation, traverse it.
  if (Category->getImplementation()) {
    ShadowContextRAII Shadow(Visited);
    LookupVisibleDecls(Category->getImplementation(), Result,
                       QualifiedNameLookup, true, Consumer, Visited,
                       IncludeDependentBases, LoadExternal);
  }
}
3689}

3691static void LookupVisibleDecls(Scope *S, LookupResult &Result,
                             UnqualUsingDirectiveSet &UDirs,
                             VisibleDeclConsumer &Consumer,
                             VisibleDeclsRecord &Visited,
                             bool LoadExternal) {
if (!S)
  return;

if (!S->getEntity() ||
    (!S->getParent() &&
     !Visited.alreadyVisitedContext(S->getEntity())) ||
    (S->getEntity())->isFunctionOrMethod()) {
  FindLocalExternScope FindLocals(Result);
  // Walk through the declarations in this Scope. The consumer might add new
  // decls to the scope as part of deserialization, so make a copy first.
  SmallVector<Decl *, 8> ScopeDecls(S->decls().begin(), S->decls().end());
  for (Decl *D : ScopeDecls) {
    if (NamedDecl *ND = dyn_cast<NamedDecl>(D))
      if ((ND = Result.getAcceptableDecl(ND))) {
        Consumer.FoundDecl(ND, Visited.checkHidden(ND), nullptr, false);
        Visited.add(ND);
      }
  }
}

// FIXME: C++ [temp.local]p8
DeclContext *Entity = nullptr;
if (S->getEntity()) {
  // Look into this scope's declaration context, along with any of its
  // parent lookup contexts (e.g., enclosing classes), up to the point
  // where we hit the context stored in the next outer scope.
  Entity = S->getEntity();
  DeclContext *OuterCtx = findOuterContext(S).first; // FIXME

  for (DeclContext *Ctx = Entity; Ctx && !Ctx->Equals(OuterCtx);
       Ctx = Ctx->getLookupParent()) {
    if (ObjCMethodDecl *Method = dyn_cast<ObjCMethodDecl>(Ctx)) {
      if (Method->isInstanceMethod()) {
        // For instance methods, look for ivars in the method's interface.
        LookupResult IvarResult(Result.getSema(), Result.getLookupName(),
                                Result.getNameLoc(), Sema::LookupMemberName);
        if (ObjCInterfaceDecl *IFace = Method->getClassInterface()) {
          LookupVisibleDecls(IFace, IvarResult, /*QualifiedNameLookup=*/false,
                             /*InBaseClass=*/false, Consumer, Visited,
                             /*IncludeDependentBases=*/false, LoadExternal);
        }
      }

      // We've already performed all of the name lookup that we need
      // to for Objective-C methods; the next context will be the
      // outer scope.
      break;
    }

    if (Ctx->isFunctionOrMethod())
      continue;

    LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/false,
                       /*InBaseClass=*/false, Consumer, Visited,
                       /*IncludeDependentBases=*/false, LoadExternal);
  }
} else if (!S->getParent()) {
  // Look into the translation unit scope. We walk through the translation
  // unit's declaration context, because the Scope itself won't have all of
  // the declarations if we loaded a precompiled header.
  // FIXME: We would like the translation unit's Scope object to point to the
  // translation unit, so we don't need this special "if" branch. However,
  // doing so would force the normal C++ name-lookup code to look into the
  // translation unit decl when the IdentifierInfo chains would suffice.
  // Once we fix that problem (which is part of a more general "don't look
  // in DeclContexts unless we have to" optimization), we can eliminate this.
  Entity = Result.getSema().Context.getTranslationUnitDecl();
  LookupVisibleDecls(Entity, Result, /*QualifiedNameLookup=*/false,
                     /*InBaseClass=*/false, Consumer, Visited,
                     /*IncludeDependentBases=*/false, LoadExternal);
}

if (Entity) {
  // Lookup visible declarations in any namespaces found by using
  // directives.
  for (const UnqualUsingEntry &UUE : UDirs.getNamespacesFor(Entity))
    LookupVisibleDecls(const_cast<DeclContext *>(UUE.getNominatedNamespace()),
                       Result, /*QualifiedNameLookup=*/false,
                       /*InBaseClass=*/false, Consumer, Visited,
                       /*IncludeDependentBases=*/false, LoadExternal);
}

// Lookup names in the parent scope.
ShadowContextRAII Shadow(Visited);
LookupVisibleDecls(S->getParent(), Result, UDirs, Consumer, Visited,
                   LoadExternal);
3782}

3784void Sema::LookupVisibleDecls(Scope *S, LookupNameKind Kind,
                            VisibleDeclConsumer &Consumer,
                            bool IncludeGlobalScope, bool LoadExternal) {
// Determine the set of using directives available during
// unqualified name lookup.
Scope *Initial = S;
UnqualUsingDirectiveSet UDirs(*this);
if (getLangOpts().CPlusPlus) {
  // Find the first namespace or translation-unit scope.
  while (S && !isNamespaceOrTranslationUnitScope(S))
    S = S->getParent();

  UDirs.visitScopeChain(Initial, S);
}
UDirs.done();

// Look for visible declarations.
LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
Result.setAllowHidden(Consumer.includeHiddenDecls());
VisibleDeclsRecord Visited;
if (!IncludeGlobalScope)
  Visited.visitedContext(Context.getTranslationUnitDecl());
ShadowContextRAII Shadow(Visited);
::LookupVisibleDecls(Initial, Result, UDirs, Consumer, Visited, LoadExternal);
3808}

3810void Sema::LookupVisibleDecls(DeclContext *Ctx, LookupNameKind Kind,
                            VisibleDeclConsumer &Consumer,
                            bool IncludeGlobalScope,
                            bool IncludeDependentBases, bool LoadExternal) {
LookupResult Result(*this, DeclarationName(), SourceLocation(), Kind);
Result.setAllowHidden(Consumer.includeHiddenDecls());
VisibleDeclsRecord Visited;
if (!IncludeGlobalScope)
  Visited.visitedContext(Context.getTranslationUnitDecl());
ShadowContextRAII Shadow(Visited);
::LookupVisibleDecls(Ctx, Result, /*QualifiedNameLookup=*/true,
                     /*InBaseClass=*/false, Consumer, Visited,
                     IncludeDependentBases, LoadExternal);
3823}

3825/// LookupOrCreateLabel - Do a name lookup of a label with the specified name.
3826/// If GnuLabelLoc is a valid source location, then this is a definition
3827/// of an __label__ label name, otherwise it is a normal label definition
3828/// or use.
3829LabelDecl *Sema::LookupOrCreateLabel(IdentifierInfo *II, SourceLocation Loc,
                                   SourceLocation GnuLabelLoc) {
// Do a lookup to see if we have a label with this name already.
NamedDecl *Res = nullptr;

if (GnuLabelLoc.isValid()) {
  // Local label definitions always shadow existing labels.
  Res = LabelDecl::Create(Context, CurContext, Loc, II, GnuLabelLoc);
  Scope *S = CurScope;
  PushOnScopeChains(Res, S, true);
  return cast<LabelDecl>(Res);
}

// Not a GNU local label.
Res = LookupSingleName(CurScope, II, Loc, LookupLabel, NotForRedeclaration);
// If we found a label, check to see if it is in the same context as us.
// When in a Block, we don't want to reuse a label in an enclosing function.
if (Res && Res->getDeclContext() != CurContext)
  Res = nullptr;
if (!Res) {
  // If not forward referenced or defined already, create the backing decl.
  Res = LabelDecl::Create(Context, CurContext, Loc, II);
  Scope *S = CurScope->getFnParent();
  assert(S && "Not in a function?")(static_cast <bool> (S && "Not in a function?")
 ? void (0) : __assert_fail ("S && \"Not in a function?\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 3852, __extension__ __PRETTY_FUNCTION__));
  PushOnScopeChains(Res, S, true);
}
return cast<LabelDecl>(Res);
3856}

3858//===----------------------------------------------------------------------===//
3859// Typo correction
3860//===----------------------------------------------------------------------===//

3862static bool isCandidateViable(CorrectionCandidateCallback &CCC,
                            TypoCorrection &Candidate) {
Candidate.setCallbackDistance(CCC.RankCandidate(Candidate));
return Candidate.getEditDistance(false) != TypoCorrection::InvalidDistance;
3866}

3868static void LookupPotentialTypoResult(Sema &SemaRef,
                                    LookupResult &Res,
                                    IdentifierInfo *Name,
                                    Scope *S, CXXScopeSpec *SS,
                                    DeclContext *MemberContext,
                                    bool EnteringContext,
                                    bool isObjCIvarLookup,
                                    bool FindHidden);

3877/// Check whether the declarations found for a typo correction are
3878/// visible. Set the correction's RequiresImport flag to true if none of the
3879/// declarations are visible, false otherwise.
3880static void checkCorrectionVisibility(Sema &SemaRef, TypoCorrection &TC) {
TypoCorrection::decl_iterator DI = TC.begin(), DE = TC.end();

for (/**/; DI != DE; ++DI)
  if (!LookupResult::isVisible(SemaRef, *DI))
    break;
// No filtering needed if all decls are visible.
if (DI == DE) {
  TC.setRequiresImport(false);
  return;
}

llvm::SmallVector<NamedDecl*, 4> NewDecls(TC.begin(), DI);
bool AnyVisibleDecls = !NewDecls.empty();

for (/**/; DI != DE; ++DI) {
  if (LookupResult::isVisible(SemaRef, *DI)) {
    if (!AnyVisibleDecls) {
      // Found a visible decl, discard all hidden ones.
      AnyVisibleDecls = true;
      NewDecls.clear();
    }
    NewDecls.push_back(*DI);
  } else if (!AnyVisibleDecls && !(*DI)->isModulePrivate())
    NewDecls.push_back(*DI);
}

if (NewDecls.empty())
  TC = TypoCorrection();
else {
  TC.setCorrectionDecls(NewDecls);
  TC.setRequiresImport(!AnyVisibleDecls);
}
3913}

3915// Fill the supplied vector with the IdentifierInfo pointers for each piece of
3916// the given NestedNameSpecifier (i.e. given a NestedNameSpecifier "foo::bar::",
3917// fill the vector with the IdentifierInfo pointers for "foo" and "bar").
3918static void getNestedNameSpecifierIdentifiers(
  NestedNameSpecifier *NNS,
  SmallVectorImpl<const IdentifierInfo*> &Identifiers) {
if (NestedNameSpecifier *Prefix = NNS->getPrefix())
  getNestedNameSpecifierIdentifiers(Prefix, Identifiers);
else
  Identifiers.clear();

const IdentifierInfo *II = nullptr;

switch (NNS->getKind()) {
case NestedNameSpecifier::Identifier:
  II = NNS->getAsIdentifier();
  break;

case NestedNameSpecifier::Namespace:
  if (NNS->getAsNamespace()->isAnonymousNamespace())
    return;
  II = NNS->getAsNamespace()->getIdentifier();
  break;

case NestedNameSpecifier::NamespaceAlias:
  II = NNS->getAsNamespaceAlias()->getIdentifier();
  break;

case NestedNameSpecifier::TypeSpecWithTemplate:
case NestedNameSpecifier::TypeSpec:
  II = QualType(NNS->getAsType(), 0).getBaseTypeIdentifier();
  break;

case NestedNameSpecifier::Global:
case NestedNameSpecifier::Super:
  return;
}

if (II)
  Identifiers.push_back(II);
3955}

3957void TypoCorrectionConsumer::FoundDecl(NamedDecl *ND, NamedDecl *Hiding,
                                     DeclContext *Ctx, bool InBaseClass) {
// Don't consider hidden names for typo correction.
if (Hiding)
  return;

// Only consider entities with identifiers for names, ignoring
// special names (constructors, overloaded operators, selectors,
// etc.).
IdentifierInfo *Name = ND->getIdentifier();
if (!Name)
  return;

// Only consider visible declarations and declarations from modules with
// names that exactly match.
if (!LookupResult::isVisible(SemaRef, ND) && Name != Typo)
  return;

FoundName(Name->getName());
3976}

3978void TypoCorrectionConsumer::FoundName(StringRef Name) {
// Compute the edit distance between the typo and the name of this
// entity, and add the identifier to the list of results.
addName(Name, nullptr);
3982}

3984void TypoCorrectionConsumer::addKeywordResult(StringRef Keyword) {
// Compute the edit distance between the typo and this keyword,
// and add the keyword to the list of results.
addName(Keyword, nullptr, nullptr, true);
3988}

3990void TypoCorrectionConsumer::addName(StringRef Name, NamedDecl *ND,
                                   NestedNameSpecifier *NNS, bool isKeyword) {
// Use a simple length-based heuristic to determine the minimum possible
// edit distance. If the minimum isn't good enough, bail out early.
StringRef TypoStr = Typo->getName();
unsigned MinED = abs((int)Name.size() - (int)TypoStr.size());
if (MinED && TypoStr.size() / MinED < 3)
  return;

// Compute an upper bound on the allowable edit distance, so that the
// edit-distance algorithm can short-circuit.
unsigned UpperBound = (TypoStr.size() + 2) / 3 + 1;
unsigned ED = TypoStr.edit_distance(Name, true, UpperBound);
if (ED >= UpperBound) return;

TypoCorrection TC(&SemaRef.Context.Idents.get(Name), ND, NNS, ED);
if (isKeyword) TC.makeKeyword();
TC.setCorrectionRange(nullptr, Result.getLookupNameInfo());
addCorrection(TC);
4009}

4011static const unsigned MaxTypoDistanceResultSets = 5;

4013void TypoCorrectionConsumer::addCorrection(TypoCorrection Correction) {
StringRef TypoStr = Typo->getName();
StringRef Name = Correction.getCorrectionAsIdentifierInfo()->getName();

// For very short typos, ignore potential corrections that have a different
// base identifier from the typo or which have a normalized edit distance
// longer than the typo itself.
if (TypoStr.size() < 3 &&
    (Name != TypoStr || Correction.getEditDistance(true) > TypoStr.size()))
  return;

// If the correction is resolved but is not viable, ignore it.
if (Correction.isResolved()) {
  checkCorrectionVisibility(SemaRef, Correction);
  if (!Correction || !isCandidateViable(*CorrectionValidator, Correction))
    return;
}

TypoResultList &CList =
    CorrectionResults[Correction.getEditDistance(false)][Name];

if (!CList.empty() && !CList.back().isResolved())
  CList.pop_back();
if (NamedDecl *NewND = Correction.getCorrectionDecl()) {
  std::string CorrectionStr = Correction.getAsString(SemaRef.getLangOpts());
  for (TypoResultList::iterator RI = CList.begin(), RIEnd = CList.end();
       RI != RIEnd; ++RI) {
    // If the Correction refers to a decl already in the result list,
    // replace the existing result if the string representation of Correction
    // comes before the current result alphabetically, then stop as there is
    // nothing more to be done to add Correction to the candidate set.
    if (RI->getCorrectionDecl() == NewND) {
      if (CorrectionStr < RI->getAsString(SemaRef.getLangOpts()))
        *RI = Correction;
      return;
    }
  }
}
if (CList.empty() || Correction.isResolved())
  CList.push_back(Correction);

while (CorrectionResults.size() > MaxTypoDistanceResultSets)
  CorrectionResults.erase(std::prev(CorrectionResults.end()));
4056}

4058void TypoCorrectionConsumer::addNamespaces(
  const llvm::MapVector<NamespaceDecl *, bool> &KnownNamespaces) {
SearchNamespaces = true;

for (auto KNPair : KnownNamespaces)
  Namespaces.addNameSpecifier(KNPair.first);

bool SSIsTemplate = false;
if (NestedNameSpecifier *NNS =
        (SS && SS->isValid()) ? SS->getScopeRep() : nullptr) {
  if (const Type *T = NNS->getAsType())
    SSIsTemplate = T->getTypeClass() == Type::TemplateSpecialization;
}
// Do not transform this into an iterator-based loop. The loop body can
// trigger the creation of further types (through lazy deserialization) and
// invalide iterators into this list.
auto &Types = SemaRef.getASTContext().getTypes();
for (unsigned I = 0; I != Types.size(); ++I) {
  const auto *TI = Types[I];
  if (CXXRecordDecl *CD = TI->getAsCXXRecordDecl()) {
    CD = CD->getCanonicalDecl();
    if (!CD->isDependentType() && !CD->isAnonymousStructOrUnion() &&
        !CD->isUnion() && CD->getIdentifier() &&
        (SSIsTemplate || !isa<ClassTemplateSpecializationDecl>(CD)) &&
        (CD->isBeingDefined() || CD->isCompleteDefinition()))
      Namespaces.addNameSpecifier(CD);
  }
}
4086}

4088const TypoCorrection &TypoCorrectionConsumer::getNextCorrection() {
if (++CurrentTCIndex < ValidatedCorrections.size())
  return ValidatedCorrections[CurrentTCIndex];

CurrentTCIndex = ValidatedCorrections.size();
while (!CorrectionResults.empty()) {
  auto DI = CorrectionResults.begin();
  if (DI->second.empty()) {
    CorrectionResults.erase(DI);
    continue;
  }

  auto RI = DI->second.begin();
  if (RI->second.empty()) {
    DI->second.erase(RI);
    performQualifiedLookups();
    continue;
  }

  TypoCorrection TC = RI->second.pop_back_val();
  if (TC.isResolved() || TC.requiresImport() || resolveCorrection(TC)) {
    ValidatedCorrections.push_back(TC);
    return ValidatedCorrections[CurrentTCIndex];
  }
}
return ValidatedCorrections[0];  // The empty correction.
4114}

4116bool TypoCorrectionConsumer::resolveCorrection(TypoCorrection &Candidate) {
IdentifierInfo *Name = Candidate.getCorrectionAsIdentifierInfo();
DeclContext *TempMemberContext = MemberContext;
CXXScopeSpec *TempSS = SS.get();
4120retry_lookup:
LookupPotentialTypoResult(SemaRef, Result, Name, S, TempSS, TempMemberContext,
                          EnteringContext,
                          CorrectionValidator->IsObjCIvarLookup,
                          Name == Typo && !Candidate.WillReplaceSpecifier());
switch (Result.getResultKind()) {
case LookupResult::NotFound:
case LookupResult::NotFoundInCurrentInstantiation:
case LookupResult::FoundUnresolvedValue:
  if (TempSS) {
    // Immediately retry the lookup without the given CXXScopeSpec
    TempSS = nullptr;
    Candidate.WillReplaceSpecifier(true);
    goto retry_lookup;
  }
  if (TempMemberContext) {
    if (SS && !TempSS)
      TempSS = SS.get();
    TempMemberContext = nullptr;
    goto retry_lookup;
  }
  if (SearchNamespaces)
    QualifiedResults.push_back(Candidate);
  break;

case LookupResult::Ambiguous:
  // We don't deal with ambiguities.
  break;

case LookupResult::Found:
case LookupResult::FoundOverloaded:
  // Store all of the Decls for overloaded symbols
  for (auto *TRD : Result)
    Candidate.addCorrectionDecl(TRD);
  checkCorrectionVisibility(SemaRef, Candidate);
  if (!isCandidateViable(*CorrectionValidator, Candidate)) {
    if (SearchNamespaces)
      QualifiedResults.push_back(Candidate);
    break;
  }
  Candidate.setCorrectionRange(SS.get(), Result.getLookupNameInfo());
  return true;
}
return false;
4164}

4166void TypoCorrectionConsumer::performQualifiedLookups() {
unsigned TypoLen = Typo->getName().size();
for (const TypoCorrection &QR : QualifiedResults) {
  for (const auto &NSI : Namespaces) {
    DeclContext *Ctx = NSI.DeclCtx;
    const Type *NSType = NSI.NameSpecifier->getAsType();

    // If the current NestedNameSpecifier refers to a class and the
    // current correction candidate is the name of that class, then skip
    // it as it is unlikely a qualified version of the class' constructor
    // is an appropriate correction.
    if (CXXRecordDecl *NSDecl = NSType ? NSType->getAsCXXRecordDecl() :
                                         nullptr) {
      if (NSDecl->getIdentifier() == QR.getCorrectionAsIdentifierInfo())
        continue;
    }

    TypoCorrection TC(QR);
    TC.ClearCorrectionDecls();
    TC.setCorrectionSpecifier(NSI.NameSpecifier);
    TC.setQualifierDistance(NSI.EditDistance);
    TC.setCallbackDistance(0); // Reset the callback distance

    // If the current correction candidate and namespace combination are
    // too far away from the original typo based on the normalized edit
    // distance, then skip performing a qualified name lookup.
    unsigned TmpED = TC.getEditDistance(true);
    if (QR.getCorrectionAsIdentifierInfo() != Typo && TmpED &&
        TypoLen / TmpED < 3)
      continue;

    Result.clear();
    Result.setLookupName(QR.getCorrectionAsIdentifierInfo());
    if (!SemaRef.LookupQualifiedName(Result, Ctx))
      continue;

    // Any corrections added below will be validated in subsequent
    // iterations of the main while() loop over the Consumer's contents.
    switch (Result.getResultKind()) {
    case LookupResult::Found:
    case LookupResult::FoundOverloaded: {
      if (SS && SS->isValid()) {
        std::string NewQualified = TC.getAsString(SemaRef.getLangOpts());
        std::string OldQualified;
        llvm::raw_string_ostream OldOStream(OldQualified);
        SS->getScopeRep()->print(OldOStream, SemaRef.getPrintingPolicy());
        OldOStream << Typo->getName();
        // If correction candidate would be an identical written qualified
        // identifer, then the existing CXXScopeSpec probably included a
        // typedef that didn't get accounted for properly.
        if (OldOStream.str() == NewQualified)
          break;
      }
      for (LookupResult::iterator TRD = Result.begin(), TRDEnd = Result.end();
           TRD != TRDEnd; ++TRD) {
        if (SemaRef.CheckMemberAccess(TC.getCorrectionRange().getBegin(),
                                      NSType ? NSType->getAsCXXRecordDecl()
                                             : nullptr,
                                      TRD.getPair()) == Sema::AR_accessible)
          TC.addCorrectionDecl(*TRD);
      }
      if (TC.isResolved()) {
        TC.setCorrectionRange(SS.get(), Result.getLookupNameInfo());
        addCorrection(TC);
      }
      break;
    }
    case LookupResult::NotFound:
    case LookupResult::NotFoundInCurrentInstantiation:
    case LookupResult::Ambiguous:
    case LookupResult::FoundUnresolvedValue:
      break;
    }
  }
}
QualifiedResults.clear();
4242}

4244TypoCorrectionConsumer::NamespaceSpecifierSet::NamespaceSpecifierSet(
  ASTContext &Context, DeclContext *CurContext, CXXScopeSpec *CurScopeSpec)
  : Context(Context), CurContextChain(buildContextChain(CurContext)) {
if (NestedNameSpecifier *NNS =
        CurScopeSpec ? CurScopeSpec->getScopeRep() : nullptr) {
  llvm::raw_string_ostream SpecifierOStream(CurNameSpecifier);
  NNS->print(SpecifierOStream, Context.getPrintingPolicy());

  getNestedNameSpecifierIdentifiers(NNS, CurNameSpecifierIdentifiers);
}
// Build the list of identifiers that would be used for an absolute
// (from the global context) NestedNameSpecifier referring to the current
// context.
for (DeclContext *C : llvm::reverse(CurContextChain)) {
  if (auto *ND = dyn_cast_or_null<NamespaceDecl>(C))
    CurContextIdentifiers.push_back(ND->getIdentifier());
}

// Add the global context as a NestedNameSpecifier
SpecifierInfo SI = {cast<DeclContext>(Context.getTranslationUnitDecl()),
                    NestedNameSpecifier::GlobalSpecifier(Context), 1};
DistanceMap[1].push_back(SI);
4266}

4268auto TypoCorrectionConsumer::NamespaceSpecifierSet::buildContextChain(
  DeclContext *Start) -> DeclContextList {
assert(Start && "Building a context chain from a null context")(static_cast <bool> (Start && "Building a context chain from a null context"
) ? void (0) : __assert_fail ("Start && \"Building a context chain from a null context\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 4270, __extension__ __PRETTY_FUNCTION__));
DeclContextList Chain;
for (DeclContext *DC = Start->getPrimaryContext(); DC != nullptr;
     DC = DC->getLookupParent()) {
  NamespaceDecl *ND = dyn_cast_or_null<NamespaceDecl>(DC);
  if (!DC->isInlineNamespace() && !DC->isTransparentContext() &&
      !(ND && ND->isAnonymousNamespace()))
    Chain.push_back(DC->getPrimaryContext());
}
return Chain;
4280}

4282unsigned
4283TypoCorrectionConsumer::NamespaceSpecifierSet::buildNestedNameSpecifier(
  DeclContextList &DeclChain, NestedNameSpecifier *&NNS) {
unsigned NumSpecifiers = 0;
for (DeclContext *C : llvm::reverse(DeclChain)) {
  if (auto *ND = dyn_cast_or_null<NamespaceDecl>(C)) {
    NNS = NestedNameSpecifier::Create(Context, NNS, ND);
    ++NumSpecifiers;
  } else if (auto *RD = dyn_cast_or_null<RecordDecl>(C)) {
    NNS = NestedNameSpecifier::Create(Context, NNS, RD->isTemplateDecl(),
                                      RD->getTypeForDecl());
    ++NumSpecifiers;
  }
}
return NumSpecifiers;
4297}

4299void TypoCorrectionConsumer::NamespaceSpecifierSet::addNameSpecifier(
  DeclContext *Ctx) {
NestedNameSpecifier *NNS = nullptr;
unsigned NumSpecifiers = 0;
DeclContextList NamespaceDeclChain(buildContextChain(Ctx));
DeclContextList FullNamespaceDeclChain(NamespaceDeclChain);

// Eliminate common elements from the two DeclContext chains.
for (DeclContext *C : llvm::reverse(CurContextChain)) {
  if (NamespaceDeclChain.empty() || NamespaceDeclChain.back() != C)
    break;
  NamespaceDeclChain.pop_back();
}

// Build the NestedNameSpecifier from what is left of the NamespaceDeclChain
NumSpecifiers = buildNestedNameSpecifier(NamespaceDeclChain, NNS);

// Add an explicit leading '::' specifier if needed.
if (NamespaceDeclChain.empty()) {
  // Rebuild the NestedNameSpecifier as a globally-qualified specifier.
  NNS = NestedNameSpecifier::GlobalSpecifier(Context);
  NumSpecifiers =
      buildNestedNameSpecifier(FullNamespaceDeclChain, NNS);
} else if (NamedDecl *ND =
               dyn_cast_or_null<NamedDecl>(NamespaceDeclChain.back())) {
  IdentifierInfo *Name = ND->getIdentifier();
  bool SameNameSpecifier = false;
  if (std::find(CurNameSpecifierIdentifiers.begin(),
                CurNameSpecifierIdentifiers.end(),
                Name) != CurNameSpecifierIdentifiers.end()) {
    std::string NewNameSpecifier;
    llvm::raw_string_ostream SpecifierOStream(NewNameSpecifier);
    SmallVector<const IdentifierInfo *, 4> NewNameSpecifierIdentifiers;
    getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
    NNS->print(SpecifierOStream, Context.getPrintingPolicy());
    SpecifierOStream.flush();
    SameNameSpecifier = NewNameSpecifier == CurNameSpecifier;
  }
  if (SameNameSpecifier ||
      std::find(CurContextIdentifiers.begin(), CurContextIdentifiers.end(),
                Name) != CurContextIdentifiers.end()) {
    // Rebuild the NestedNameSpecifier as a globally-qualified specifier.
    NNS = NestedNameSpecifier::GlobalSpecifier(Context);
    NumSpecifiers =
        buildNestedNameSpecifier(FullNamespaceDeclChain, NNS);
  }
}

// If the built NestedNameSpecifier would be replacing an existing
// NestedNameSpecifier, use the number of component identifiers that
// would need to be changed as the edit distance instead of the number
// of components in the built NestedNameSpecifier.
if (NNS && !CurNameSpecifierIdentifiers.empty()) {
  SmallVector<const IdentifierInfo*, 4> NewNameSpecifierIdentifiers;
  getNestedNameSpecifierIdentifiers(NNS, NewNameSpecifierIdentifiers);
  NumSpecifiers = llvm::ComputeEditDistance(
      llvm::makeArrayRef(CurNameSpecifierIdentifiers),
      llvm::makeArrayRef(NewNameSpecifierIdentifiers));
}

SpecifierInfo SI = {Ctx, NNS, NumSpecifiers};
DistanceMap[NumSpecifiers].push_back(SI);
4361}

4363/// Perform name lookup for a possible result for typo correction.
4364static void LookupPotentialTypoResult(Sema &SemaRef,
                                    LookupResult &Res,
                                    IdentifierInfo *Name,
                                    Scope *S, CXXScopeSpec *SS,
                                    DeclContext *MemberContext,
                                    bool EnteringContext,
                                    bool isObjCIvarLookup,
                                    bool FindHidden) {
Res.suppressDiagnostics();
Res.clear();
Res.setLookupName(Name);
Res.setAllowHidden(FindHidden);
if (MemberContext) {
  if (ObjCInterfaceDecl *Class = dyn_cast<ObjCInterfaceDecl>(MemberContext)) {
    if (isObjCIvarLookup) {
      if (ObjCIvarDecl *Ivar = Class->lookupInstanceVariable(Name)) {
        Res.addDecl(Ivar);
        Res.resolveKind();
        return;
      }
    }

    if (ObjCPropertyDecl *Prop = Class->FindPropertyDeclaration(
            Name, ObjCPropertyQueryKind::OBJC_PR_query_instance)) {
      Res.addDecl(Prop);
      Res.resolveKind();
      return;
    }
  }

  SemaRef.LookupQualifiedName(Res, MemberContext);
  return;
}

SemaRef.LookupParsedName(Res, S, SS, /*AllowBuiltinCreation=*/false,
                         EnteringContext);

// Fake ivar lookup; this should really be part of
// LookupParsedName.
if (ObjCMethodDecl *Method = SemaRef.getCurMethodDecl()) {
  if (Method->isInstanceMethod() && Method->getClassInterface() &&
      (Res.empty() ||
       (Res.isSingleResult() &&
        Res.getFoundDecl()->isDefinedOutsideFunctionOrMethod()))) {
     if (ObjCIvarDecl *IV
           = Method->getClassInterface()->lookupInstanceVariable(Name)) {
       Res.addDecl(IV);
       Res.resolveKind();
     }
   }
}
4415}

4417/// Add keywords to the consumer as possible typo corrections.
4418static void AddKeywordsToConsumer(Sema &SemaRef,
                                TypoCorrectionConsumer &Consumer,
                                Scope *S, CorrectionCandidateCallback &CCC,
                                bool AfterNestedNameSpecifier) {
if (AfterNestedNameSpecifier) {
  // For 'X::', we know exactly which keywords can appear next.
  Consumer.addKeywordResult("template");
  if (CCC.WantExpressionKeywords)
    Consumer.addKeywordResult("operator");
  return;
}

if (CCC.WantObjCSuper)
  Consumer.addKeywordResult("super");

if (CCC.WantTypeSpecifiers) {
  // Add type-specifier keywords to the set of results.
  static const char *const CTypeSpecs[] = {
    "char", "const", "double", "enum", "float", "int", "long", "short",
    "signed", "struct", "union", "unsigned", "void", "volatile", 
    "_Complex", "_Imaginary",
    // storage-specifiers as well
    "extern", "inline", "static", "typedef"
  };

  const unsigned NumCTypeSpecs = llvm::array_lengthof(CTypeSpecs);
  for (unsigned I = 0; I != NumCTypeSpecs; ++I)
    Consumer.addKeywordResult(CTypeSpecs[I]);

  if (SemaRef.getLangOpts().C99)
    Consumer.addKeywordResult("restrict");
  if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus)
    Consumer.addKeywordResult("bool");
  else if (SemaRef.getLangOpts().C99)
    Consumer.addKeywordResult("_Bool");
  
  if (SemaRef.getLangOpts().CPlusPlus) {
    Consumer.addKeywordResult("class");
    Consumer.addKeywordResult("typename");
    Consumer.addKeywordResult("wchar_t");

    if (SemaRef.getLangOpts().CPlusPlus11) {
      Consumer.addKeywordResult("char16_t");
      Consumer.addKeywordResult("char32_t");
      Consumer.addKeywordResult("constexpr");
      Consumer.addKeywordResult("decltype");
      Consumer.addKeywordResult("thread_local");
    }
  }

  if (SemaRef.getLangOpts().GNUKeywords)
    Consumer.addKeywordResult("typeof");
} else if (CCC.WantFunctionLikeCasts) {
  static const char *const CastableTypeSpecs[] = {
    "char", "double", "float", "int", "long", "short",
    "signed", "unsigned", "void"
  };
  for (auto *kw : CastableTypeSpecs)
    Consumer.addKeywordResult(kw);
}

if (CCC.WantCXXNamedCasts && SemaRef.getLangOpts().CPlusPlus) {
  Consumer.addKeywordResult("const_cast");
  Consumer.addKeywordResult("dynamic_cast");
  Consumer.addKeywordResult("reinterpret_cast");
  Consumer.addKeywordResult("static_cast");
}

if (CCC.WantExpressionKeywords) {
  Consumer.addKeywordResult("sizeof");
  if (SemaRef.getLangOpts().Bool || SemaRef.getLangOpts().CPlusPlus) {
    Consumer.addKeywordResult("false");
    Consumer.addKeywordResult("true");
  }

  if (SemaRef.getLangOpts().CPlusPlus) {
    static const char *const CXXExprs[] = {
      "delete", "new", "operator", "throw", "typeid"
    };
    const unsigned NumCXXExprs = llvm::array_lengthof(CXXExprs);
    for (unsigned I = 0; I != NumCXXExprs; ++I)
      Consumer.addKeywordResult(CXXExprs[I]);

    if (isa<CXXMethodDecl>(SemaRef.CurContext) &&
        cast<CXXMethodDecl>(SemaRef.CurContext)->isInstance())
      Consumer.addKeywordResult("this");

    if (SemaRef.getLangOpts().CPlusPlus11) {
      Consumer.addKeywordResult("alignof");
      Consumer.addKeywordResult("nullptr");
    }
  }

  if (SemaRef.getLangOpts().C11) {
    // FIXME: We should not suggest _Alignof if the alignof macro
    // is present.
    Consumer.addKeywordResult("_Alignof");
  }
}

if (CCC.WantRemainingKeywords) {
  if (SemaRef.getCurFunctionOrMethodDecl() || SemaRef.getCurBlock()) {
    // Statements.
    static const char *const CStmts[] = {
      "do", "else", "for", "goto", "if", "return", "switch", "while" };
    const unsigned NumCStmts = llvm::array_lengthof(CStmts);
    for (unsigned I = 0; I != NumCStmts; ++I)
      Consumer.addKeywordResult(CStmts[I]);

    if (SemaRef.getLangOpts().CPlusPlus) {
      Consumer.addKeywordResult("catch");
      Consumer.addKeywordResult("try");
    }

    if (S && S->getBreakParent())
      Consumer.addKeywordResult("break");

    if (S && S->getContinueParent())
      Consumer.addKeywordResult("continue");

    if (SemaRef.getCurFunction() &&
        !SemaRef.getCurFunction()->SwitchStack.empty()) {
      Consumer.addKeywordResult("case");
      Consumer.addKeywordResult("default");
    }
  } else {
    if (SemaRef.getLangOpts().CPlusPlus) {
      Consumer.addKeywordResult("namespace");
      Consumer.addKeywordResult("template");
    }

    if (S && S->isClassScope()) {
      Consumer.addKeywordResult("explicit");
      Consumer.addKeywordResult("friend");
      Consumer.addKeywordResult("mutable");
      Consumer.addKeywordResult("private");
      Consumer.addKeywordResult("protected");
      Consumer.addKeywordResult("public");
      Consumer.addKeywordResult("virtual");
    }
  }

  if (SemaRef.getLangOpts().CPlusPlus) {
    Consumer.addKeywordResult("using");

    if (SemaRef.getLangOpts().CPlusPlus11)
      Consumer.addKeywordResult("static_assert");
  }
}
4567}

4569std::unique_ptr<TypoCorrectionConsumer> Sema::makeTypoCorrectionConsumer(
  const DeclarationNameInfo &TypoName, Sema::LookupNameKind LookupKind,
  Scope *S, CXXScopeSpec *SS,
  std::unique_ptr<CorrectionCandidateCallback> CCC,
  DeclContext *MemberContext, bool EnteringContext,
  const ObjCObjectPointerType *OPT, bool ErrorRecovery) {

if (Diags.hasFatalErrorOccurred() || !getLangOpts().SpellChecking ||
3
←
Assuming the condition is false→
4
←
Assuming the condition is false→
6
←
Taking false branch→
    DisableTypoCorrection)
5
←
Assuming the condition is false→
  return nullptr;

// In Microsoft mode, don't perform typo correction in a template member
// function dependent context because it interferes with the "lookup into
// dependent bases of class templates" feature.
if (getLangOpts().MSVCCompat && CurContext->isDependentContext() &&
7
←
Assuming the condition is false→
    isa<CXXMethodDecl>(CurContext))
  return nullptr;

// We only attempt to correct typos for identifiers.
IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
if (!Typo)
8
←
Assuming 'Typo' is non-null→
9
←
Taking false branch→
  return nullptr;

// If the scope specifier itself was invalid, don't try to correct
// typos.
if (SS && SS->isInvalid())
10
←
Assuming 'SS' is null→
  return nullptr;

// Never try to correct typos during any kind of code synthesis.
if (!CodeSynthesisContexts.empty())
11
←
Taking false branch→
  return nullptr;

// Don't try to correct 'super'.
if (S && S->isInObjcMethodScope() && Typo == getSuperIdentifier())
12
←
Assuming 'S' is null→
  return nullptr;

// Abort if typo correction already failed for this specific typo.
IdentifierSourceLocations::iterator locs = TypoCorrectionFailures.find(Typo);
if (locs != TypoCorrectionFailures.end() &&
13
←
Assuming the condition is false→
14
←
Taking false branch→
    locs->second.count(TypoName.getLoc()))
  return nullptr;

// Don't try to correct the identifier "vector" when in AltiVec mode.
// TODO: Figure out why typo correction misbehaves in this case, fix it, and
// remove this workaround.
if ((getLangOpts().AltiVec || getLangOpts().ZVector) && Typo->isStr("vector"))
15
←
Assuming the condition is false→
16
←
Assuming the condition is false→
  return nullptr;

// Provide a stop gap for files that are just seriously broken.  Trying
// to correct all typos can turn into a HUGE performance penalty, causing
// some files to take minutes to get rejected by the parser.
unsigned Limit = getDiagnostics().getDiagnosticOptions().SpellCheckingLimit;
if (Limit && TyposCorrected >= Limit)
17
←
Assuming 'Limit' is 0→
  return nullptr;
++TyposCorrected;

// If we're handling a missing symbol error, using modules, and the
// special search all modules option is used, look for a missing import.
if (ErrorRecovery && getLangOpts().Modules &&
    getLangOpts().ModulesSearchAll) {
  // The following has the side effect of loading the missing module.
  getModuleLoader().lookupMissingImports(Typo->getName(),
                                         TypoName.getLocStart());
}

CorrectionCandidateCallback &CCCRef = *CCC;
auto Consumer = llvm::make_unique<TypoCorrectionConsumer>(
18
←
Calling 'make_unique<clang::TypoCorrectionConsumer, clang::Sema &, const clang::DeclarationNameInfo &, clang::Sema::LookupNameKind &, clang::Scope *&, clang::CXXScopeSpec *&, std::unique_ptr<clang::CorrectionCandidateCallback, std::default_delete<clang::CorrectionCandidateCallback> >, clang::DeclContext *&, bool &>'→
25
←
Returning; memory was released→
    *this, TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
    EnteringContext);

// Perform name lookup to find visible, similarly-named entities.
bool IsUnqualifiedLookup = false;
DeclContext *QualifiedDC = MemberContext;
if (MemberContext) {
26
←
Assuming 'MemberContext' is null→
27
←
Taking false branch→
  LookupVisibleDecls(MemberContext, LookupKind, *Consumer);

  // Look in qualified interfaces.
  if (OPT) {
    for (auto *I : OPT->quals())
      LookupVisibleDecls(I, LookupKind, *Consumer);
  }
} else if (SS && SS->isSet()) {
  QualifiedDC = computeDeclContext(*SS, EnteringContext);
  if (!QualifiedDC)
    return nullptr;

  LookupVisibleDecls(QualifiedDC, LookupKind, *Consumer);
} else {
  IsUnqualifiedLookup = true;
}

// Determine whether we are going to search in the various namespaces for
// corrections.
bool SearchNamespaces
  = getLangOpts().CPlusPlus &&
28
←
Assuming the condition is false→
    (IsUnqualifiedLookup || (SS && SS->isSet()));

if (IsUnqualifiedLookup || SearchNamespaces) {
  // For unqualified lookup, look through all of the names that we have
  // seen in this translation unit.
  // FIXME: Re-add the ability to skip very unlikely potential corrections.
  for (const auto &I : Context.Idents)
    Consumer->FoundName(I.getKey());

  // Walk through identifiers in external identifier sources.
  // FIXME: Re-add the ability to skip very unlikely potential corrections.
  if (IdentifierInfoLookup *External
29
←
Assuming 'External' is null→
30
←
Taking false branch→
                          = Context.Idents.getExternalIdentifierLookup()) {
    std::unique_ptr<IdentifierIterator> Iter(External->getIdentifiers());
    do {
      StringRef Name = Iter->Next();
      if (Name.empty())
        break;

      Consumer->FoundName(Name);
    } while (true);
  }
}

AddKeywordsToConsumer(*this, *Consumer, S, CCCRef, SS && SS->isNotEmpty());
31
←
Use of memory after it is freed

// Build the NestedNameSpecifiers for the KnownNamespaces, if we're going
// to search those namespaces.
if (SearchNamespaces) {
  // Load any externally-known namespaces.
  if (ExternalSource && !LoadedExternalKnownNamespaces) {
    SmallVector<NamespaceDecl *, 4> ExternalKnownNamespaces;
    LoadedExternalKnownNamespaces = true;
    ExternalSource->ReadKnownNamespaces(ExternalKnownNamespaces);
    for (auto *N : ExternalKnownNamespaces)
      KnownNamespaces[N] = true;
  }

  Consumer->addNamespaces(KnownNamespaces);
}

return Consumer;
4706}

4708/// Try to "correct" a typo in the source code by finding
4709/// visible declarations whose names are similar to the name that was
4710/// present in the source code.
4711///
4712/// \param TypoName the \c DeclarationNameInfo structure that contains
4713/// the name that was present in the source code along with its location.
4714///
4715/// \param LookupKind the name-lookup criteria used to search for the name.
4716///
4717/// \param S the scope in which name lookup occurs.
4718///
4719/// \param SS the nested-name-specifier that precedes the name we're
4720/// looking for, if present.
4721///
4722/// \param CCC A CorrectionCandidateCallback object that provides further
4723/// validation of typo correction candidates. It also provides flags for
4724/// determining the set of keywords permitted.
4725///
4726/// \param MemberContext if non-NULL, the context in which to look for
4727/// a member access expression.
4728///
4729/// \param EnteringContext whether we're entering the context described by
4730/// the nested-name-specifier SS.
4731///
4732/// \param OPT when non-NULL, the search for visible declarations will
4733/// also walk the protocols in the qualified interfaces of \p OPT.
4734///
4735/// \returns a \c TypoCorrection containing the corrected name if the typo
4736/// along with information such as the \c NamedDecl where the corrected name
4737/// was declared, and any additional \c NestedNameSpecifier needed to access
4738/// it (C++ only). The \c TypoCorrection is empty if there is no correction.
4739TypoCorrection Sema::CorrectTypo(const DeclarationNameInfo &TypoName,
                               Sema::LookupNameKind LookupKind,
                               Scope *S, CXXScopeSpec *SS,
                               std::unique_ptr<CorrectionCandidateCallback> CCC,
                               CorrectTypoKind Mode,
                               DeclContext *MemberContext,
                               bool EnteringContext,
                               const ObjCObjectPointerType *OPT,
                               bool RecordFailure) {
assert(CCC && "CorrectTypo requires a CorrectionCandidateCallback")(static_cast <bool> (CCC && "CorrectTypo requires a CorrectionCandidateCallback"
) ? void (0) : __assert_fail ("CCC && \"CorrectTypo requires a CorrectionCandidateCallback\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 4748, __extension__ __PRETTY_FUNCTION__));

// Always let the ExternalSource have the first chance at correction, even
// if we would otherwise have given up.
if (ExternalSource) {
  if (TypoCorrection Correction = ExternalSource->CorrectTypo(
      TypoName, LookupKind, S, SS, *CCC, MemberContext, EnteringContext, OPT))
    return Correction;
}

// Ugly hack equivalent to CTC == CTC_ObjCMessageReceiver;
// WantObjCSuper is only true for CTC_ObjCMessageReceiver and for
// some instances of CTC_Unknown, while WantRemainingKeywords is true
// for CTC_Unknown but not for CTC_ObjCMessageReceiver.
bool ObjCMessageReceiver = CCC->WantObjCSuper && !CCC->WantRemainingKeywords;

IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
auto Consumer = makeTypoCorrectionConsumer(
    TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
    EnteringContext, OPT, Mode == CTK_ErrorRecovery);

if (!Consumer)
  return TypoCorrection();

// If we haven't found anything, we're done.
if (Consumer->empty())
  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);

// Make sure the best edit distance (prior to adding any namespace qualifiers)
// is not more that about a third of the length of the typo's identifier.
unsigned ED = Consumer->getBestEditDistance(true);
unsigned TypoLen = Typo->getName().size();
if (ED > 0 && TypoLen / ED < 3)
  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);

TypoCorrection BestTC = Consumer->getNextCorrection();
TypoCorrection SecondBestTC = Consumer->getNextCorrection();
if (!BestTC)
  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);

ED = BestTC.getEditDistance();

if (TypoLen >= 3 && ED > 0 && TypoLen / ED < 3) {
  // If this was an unqualified lookup and we believe the callback
  // object wouldn't have filtered out possible corrections, note
  // that no correction was found.
  return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);
}

// If only a single name remains, return that result.
if (!SecondBestTC ||
    SecondBestTC.getEditDistance(false) > BestTC.getEditDistance(false)) {
  const TypoCorrection &Result = BestTC;

  // Don't correct to a keyword that's the same as the typo; the keyword
  // wasn't actually in scope.
  if (ED == 0 && Result.isKeyword())
    return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);

  TypoCorrection TC = Result;
  TC.setCorrectionRange(SS, TypoName);
  checkCorrectionVisibility(*this, TC);
  return TC;
} else if (SecondBestTC && ObjCMessageReceiver) {
  // Prefer 'super' when we're completing in a message-receiver
  // context.

  if (BestTC.getCorrection().getAsString() != "super") {
    if (SecondBestTC.getCorrection().getAsString() == "super")
      BestTC = SecondBestTC;
    else if ((*Consumer)["super"].front().isKeyword())
      BestTC = (*Consumer)["super"].front();
  }
  // Don't correct to a keyword that's the same as the typo; the keyword
  // wasn't actually in scope.
  if (BestTC.getEditDistance() == 0 ||
      BestTC.getCorrection().getAsString() != "super")
    return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure);

  BestTC.setCorrectionRange(SS, TypoName);
  return BestTC;
}

// Record the failure's location if needed and return an empty correction. If
// this was an unqualified lookup and we believe the callback object did not
// filter out possible corrections, also cache the failure for the typo.
return FailedCorrection(Typo, TypoName.getLoc(), RecordFailure && !SecondBestTC);
4835}

4837/// Try to "correct" a typo in the source code by finding
4838/// visible declarations whose names are similar to the name that was
4839/// present in the source code.
4840///
4841/// \param TypoName the \c DeclarationNameInfo structure that contains
4842/// the name that was present in the source code along with its location.
4843///
4844/// \param LookupKind the name-lookup criteria used to search for the name.
4845///
4846/// \param S the scope in which name lookup occurs.
4847///
4848/// \param SS the nested-name-specifier that precedes the name we're
4849/// looking for, if present.
4850///
4851/// \param CCC A CorrectionCandidateCallback object that provides further
4852/// validation of typo correction candidates. It also provides flags for
4853/// determining the set of keywords permitted.
4854///
4855/// \param TDG A TypoDiagnosticGenerator functor that will be used to print
4856/// diagnostics when the actual typo correction is attempted.
4857///
4858/// \param TRC A TypoRecoveryCallback functor that will be used to build an
4859/// Expr from a typo correction candidate.
4860///
4861/// \param MemberContext if non-NULL, the context in which to look for
4862/// a member access expression.
4863///
4864/// \param EnteringContext whether we're entering the context described by
4865/// the nested-name-specifier SS.
4866///
4867/// \param OPT when non-NULL, the search for visible declarations will
4868/// also walk the protocols in the qualified interfaces of \p OPT.
4869///
4870/// \returns a new \c TypoExpr that will later be replaced in the AST with an
4871/// Expr representing the result of performing typo correction, or nullptr if
4872/// typo correction is not possible. If nullptr is returned, no diagnostics will
4873/// be emitted and it is the responsibility of the caller to emit any that are
4874/// needed.
4875TypoExpr *Sema::CorrectTypoDelayed(
  const DeclarationNameInfo &TypoName, Sema::LookupNameKind LookupKind,
  Scope *S, CXXScopeSpec *SS,
  std::unique_ptr<CorrectionCandidateCallback> CCC,
  TypoDiagnosticGenerator TDG, TypoRecoveryCallback TRC, CorrectTypoKind Mode,
  DeclContext *MemberContext, bool EnteringContext,
  const ObjCObjectPointerType *OPT) {
assert(CCC && "CorrectTypoDelayed requires a CorrectionCandidateCallback")(static_cast <bool> (CCC && "CorrectTypoDelayed requires a CorrectionCandidateCallback"
) ? void (0) : __assert_fail ("CCC && \"CorrectTypoDelayed requires a CorrectionCandidateCallback\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 4882, __extension__ __PRETTY_FUNCTION__));

auto Consumer = makeTypoCorrectionConsumer(
2
←
Calling 'Sema::makeTypoCorrectionConsumer'→
    TypoName, LookupKind, S, SS, std::move(CCC), MemberContext,
    EnteringContext, OPT, Mode == CTK_ErrorRecovery);
1
Assuming 'Mode' is not equal to CTK_ErrorRecovery→

// Give the external sema source a chance to correct the typo.
TypoCorrection ExternalTypo;
if (ExternalSource && Consumer) {
  ExternalTypo = ExternalSource->CorrectTypo(
      TypoName, LookupKind, S, SS, *Consumer->getCorrectionValidator(),
      MemberContext, EnteringContext, OPT);
  if (ExternalTypo)
    Consumer->addCorrection(ExternalTypo);
}

if (!Consumer || Consumer->empty())
  return nullptr;

// Make sure the best edit distance (prior to adding any namespace qualifiers)
// is not more that about a third of the length of the typo's identifier.
unsigned ED = Consumer->getBestEditDistance(true);
IdentifierInfo *Typo = TypoName.getName().getAsIdentifierInfo();
if (!ExternalTypo && ED > 0 && Typo->getName().size() / ED < 3)
  return nullptr;

ExprEvalContexts.back().NumTypos++;
return createDelayedTypo(std::move(Consumer), std::move(TDG), std::move(TRC));
4910}

4912void TypoCorrection::addCorrectionDecl(NamedDecl *CDecl) {
if (!CDecl) return;

if (isKeyword())
  CorrectionDecls.clear();

CorrectionDecls.push_back(CDecl);

if (!CorrectionName)
  CorrectionName = CDecl->getDeclName();
4922}

4924std::string TypoCorrection::getAsString(const LangOptions &LO) const {
if (CorrectionNameSpec) {
  std::string tmpBuffer;
  llvm::raw_string_ostream PrefixOStream(tmpBuffer);
  CorrectionNameSpec->print(PrefixOStream, PrintingPolicy(LO));
  PrefixOStream << CorrectionName;
  return PrefixOStream.str();
}

return CorrectionName.getAsString();
4934}

4936bool CorrectionCandidateCallback::ValidateCandidate(
  const TypoCorrection &candidate) {
if (!candidate.isResolved())
  return true;

if (candidate.isKeyword())
  return WantTypeSpecifiers || WantExpressionKeywords || WantCXXNamedCasts ||
         WantRemainingKeywords || WantObjCSuper;

bool HasNonType = false;
bool HasStaticMethod = false;
bool HasNonStaticMethod = false;
for (Decl *D : candidate) {
  if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(D))
    D = FTD->getTemplatedDecl();
  if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(D)) {
    if (Method->isStatic())
      HasStaticMethod = true;
    else
      HasNonStaticMethod = true;
  }
  if (!isa<TypeDecl>(D))
    HasNonType = true;
}

if (IsAddressOfOperand && HasNonStaticMethod && !HasStaticMethod &&
    !candidate.getCorrectionSpecifier())
  return false;

return WantTypeSpecifiers || HasNonType;
4966}

4968FunctionCallFilterCCC::FunctionCallFilterCCC(Sema &SemaRef, unsigned NumArgs,
                                           bool HasExplicitTemplateArgs,
                                           MemberExpr *ME)
  : NumArgs(NumArgs), HasExplicitTemplateArgs(HasExplicitTemplateArgs),
    CurContext(SemaRef.CurContext), MemberFn(ME) {
WantTypeSpecifiers = false;
WantFunctionLikeCasts = SemaRef.getLangOpts().CPlusPlus && NumArgs == 1;
WantRemainingKeywords = false;
4976}

4978bool FunctionCallFilterCCC::ValidateCandidate(const TypoCorrection &candidate) {
if (!candidate.getCorrectionDecl())
  return candidate.isKeyword();

for (auto *C : candidate) {
  FunctionDecl *FD = nullptr;
  NamedDecl *ND = C->getUnderlyingDecl();
  if (FunctionTemplateDecl *FTD = dyn_cast<FunctionTemplateDecl>(ND))
    FD = FTD->getTemplatedDecl();
  if (!HasExplicitTemplateArgs && !FD) {
    if (!(FD = dyn_cast<FunctionDecl>(ND)) && isa<ValueDecl>(ND)) {
      // If the Decl is neither a function nor a template function,
      // determine if it is a pointer or reference to a function. If so,
      // check against the number of arguments expected for the pointee.
      QualType ValType = cast<ValueDecl>(ND)->getType();
      if (ValType.isNull())
        continue;
      if (ValType->isAnyPointerType() || ValType->isReferenceType())
        ValType = ValType->getPointeeType();
      if (const FunctionProtoType *FPT = ValType->getAs<FunctionProtoType>())
        if (FPT->getNumParams() == NumArgs)
          return true;
    }
  }

  // Skip the current candidate if it is not a FunctionDecl or does not accept
  // the current number of arguments.
  if (!FD || !(FD->getNumParams() >= NumArgs &&
               FD->getMinRequiredArguments() <= NumArgs))
    continue;

  // If the current candidate is a non-static C++ method, skip the candidate
  // unless the method being corrected--or the current DeclContext, if the
  // function being corrected is not a method--is a method in the same class
  // or a descendent class of the candidate's parent class.
  if (CXXMethodDecl *MD = dyn_cast<CXXMethodDecl>(FD)) {
    if (MemberFn || !MD->isStatic()) {
      CXXMethodDecl *CurMD =
          MemberFn
              ? dyn_cast_or_null<CXXMethodDecl>(MemberFn->getMemberDecl())
              : dyn_cast_or_null<CXXMethodDecl>(CurContext);
      CXXRecordDecl *CurRD =
          CurMD ? CurMD->getParent()->getCanonicalDecl() : nullptr;
      CXXRecordDecl *RD = MD->getParent()->getCanonicalDecl();
      if (!CurRD || (CurRD != RD && !CurRD->isDerivedFrom(RD)))
        continue;
    }
  }
  return true;
}
return false;
5029}

5031void Sema::diagnoseTypo(const TypoCorrection &Correction,
                      const PartialDiagnostic &TypoDiag,
                      bool ErrorRecovery) {
diagnoseTypo(Correction, TypoDiag, PDiag(diag::note_previous_decl),
             ErrorRecovery);
5036}

5038/// Find which declaration we should import to provide the definition of
5039/// the given declaration.
5040static NamedDecl *getDefinitionToImport(NamedDecl *D) {
if (VarDecl *VD = dyn_cast<VarDecl>(D))
  return VD->getDefinition();
if (FunctionDecl *FD = dyn_cast<FunctionDecl>(D))
  return FD->getDefinition();
if (TagDecl *TD = dyn_cast<TagDecl>(D))
  return TD->getDefinition();
if (ObjCInterfaceDecl *ID = dyn_cast<ObjCInterfaceDecl>(D))
  return ID->getDefinition();
if (ObjCProtocolDecl *PD = dyn_cast<ObjCProtocolDecl>(D))
  return PD->getDefinition();
if (TemplateDecl *TD = dyn_cast<TemplateDecl>(D))
  return getDefinitionToImport(TD->getTemplatedDecl());
return nullptr;
5054}

5056void Sema::diagnoseMissingImport(SourceLocation Loc, NamedDecl *Decl,
                               MissingImportKind MIK, bool Recover) {
// Suggest importing a module providing the definition of this entity, if
// possible.
NamedDecl *Def = getDefinitionToImport(Decl);
if (!Def)
  Def = Decl;

Module *Owner = getOwningModule(Decl);
assert(Owner && "definition of hidden declaration is not in a module")(static_cast <bool> (Owner && "definition of hidden declaration is not in a module"
) ? void (0) : __assert_fail ("Owner && \"definition of hidden declaration is not in a module\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 5065, __extension__ __PRETTY_FUNCTION__));

llvm::SmallVector<Module*, 8> OwningModules;
OwningModules.push_back(Owner);
auto Merged = Context.getModulesWithMergedDefinition(Decl);
OwningModules.insert(OwningModules.end(), Merged.begin(), Merged.end());

diagnoseMissingImport(Loc, Decl, Decl->getLocation(), OwningModules, MIK,
                      Recover);
5074}

5076/// Get a "quoted.h" or <angled.h> include path to use in a diagnostic
5077/// suggesting the addition of a #include of the specified file.
5078static std::string getIncludeStringForHeader(Preprocessor &PP,
                                           const FileEntry *E) {
bool IsSystem;
auto Path =
    PP.getHeaderSearchInfo().suggestPathToFileForDiagnostics(E, &IsSystem);
return (IsSystem ? '<' : '"') + Path + (IsSystem ? '>' : '"');
5084}

5086void Sema::diagnoseMissingImport(SourceLocation UseLoc, NamedDecl *Decl,
                               SourceLocation DeclLoc,
                               ArrayRef<Module *> Modules,
                               MissingImportKind MIK, bool Recover) {
assert(!Modules.empty())(static_cast <bool> (!Modules.empty()) ? void (0) : __assert_fail
 ("!Modules.empty()", "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 5090, __extension__ __PRETTY_FUNCTION__));

// Weed out duplicates from module list.
llvm::SmallVector<Module*, 8> UniqueModules;
llvm::SmallDenseSet<Module*, 8> UniqueModuleSet;
for (auto *M : Modules)
  if (UniqueModuleSet.insert(M).second)
    UniqueModules.push_back(M);
Modules = UniqueModules;

if (Modules.size() > 1) {
  std::string ModuleList;
  unsigned N = 0;
  for (Module *M : Modules) {
    ModuleList += "\n        ";
    if (++N == 5 && N != Modules.size()) {
      ModuleList += "[...]";
      break;
    }
    ModuleList += M->getFullModuleName();
  }

  Diag(UseLoc, diag::err_module_unimported_use_multiple)
    << (int)MIK << Decl << ModuleList;
} else if (const FileEntry *E = PP.getModuleHeaderToIncludeForDiagnostics(
               UseLoc, Modules[0], DeclLoc)) {
  // The right way to make the declaration visible is to include a header;
  // suggest doing so.
  //
  // FIXME: Find a smart place to suggest inserting a #include, and add
  // a FixItHint there.
  Diag(UseLoc, diag::err_module_unimported_use_header)
    << (int)MIK << Decl << Modules[0]->getFullModuleName()
    << getIncludeStringForHeader(PP, E);
} else {
  // FIXME: Add a FixItHint that imports the corresponding module.
  Diag(UseLoc, diag::err_module_unimported_use)
    << (int)MIK << Decl << Modules[0]->getFullModuleName();
}

unsigned DiagID;
switch (MIK) {
case MissingImportKind::Declaration:
  DiagID = diag::note_previous_declaration;
  break;
case MissingImportKind::Definition:
  DiagID = diag::note_previous_definition;
  break;
case MissingImportKind::DefaultArgument:
  DiagID = diag::note_default_argument_declared_here;
  break;
case MissingImportKind::ExplicitSpecialization:
  DiagID = diag::note_explicit_specialization_declared_here;
  break;
case MissingImportKind::PartialSpecialization:
  DiagID = diag::note_partial_specialization_declared_here;
  break;
}
Diag(DeclLoc, DiagID);

// Try to recover by implicitly importing this module.
if (Recover)
  createImplicitModuleImportForErrorRecovery(UseLoc, Modules[0]);
5153}

5155/// Diagnose a successfully-corrected typo. Separated from the correction
5156/// itself to allow external validation of the result, etc.
5157///
5158/// \param Correction The result of performing typo correction.
5159/// \param TypoDiag The diagnostic to produce. This will have the corrected
5160///        string added to it (and usually also a fixit).
5161/// \param PrevNote A note to use when indicating the location of the entity to
5162///        which we are correcting. Will have the correction string added to it.
5163/// \param ErrorRecovery If \c true (the default), the caller is going to
5164///        recover from the typo as if the corrected string had been typed.
5165///        In this case, \c PDiag must be an error, and we will attach a fixit
5166///        to it.
5167void Sema::diagnoseTypo(const TypoCorrection &Correction,
                      const PartialDiagnostic &TypoDiag,
                      const PartialDiagnostic &PrevNote,
                      bool ErrorRecovery) {
std::string CorrectedStr = Correction.getAsString(getLangOpts());
std::string CorrectedQuotedStr = Correction.getQuoted(getLangOpts());
FixItHint FixTypo = FixItHint::CreateReplacement(
    Correction.getCorrectionRange(), CorrectedStr);

// Maybe we're just missing a module import.
if (Correction.requiresImport()) {
  NamedDecl *Decl = Correction.getFoundDecl();
  assert(Decl && "import required but no declaration to import")(static_cast <bool> (Decl && "import required but no declaration to import"
) ? void (0) : __assert_fail ("Decl && \"import required but no declaration to import\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 5179, __extension__ __PRETTY_FUNCTION__));

  diagnoseMissingImport(Correction.getCorrectionRange().getBegin(), Decl,
                        MissingImportKind::Declaration, ErrorRecovery);
  return;
}

Diag(Correction.getCorrectionRange().getBegin(), TypoDiag)
  << CorrectedQuotedStr << (ErrorRecovery ? FixTypo : FixItHint());

NamedDecl *ChosenDecl =
    Correction.isKeyword() ? nullptr : Correction.getFoundDecl();
if (PrevNote.getDiagID() && ChosenDecl)
  Diag(ChosenDecl->getLocation(), PrevNote)
    << CorrectedQuotedStr << (ErrorRecovery ? FixItHint() : FixTypo);

// Add any extra diagnostics.
for (const PartialDiagnostic &PD : Correction.getExtraDiagnostics())
  Diag(Correction.getCorrectionRange().getBegin(), PD);
5198}

5200TypoExpr *Sema::createDelayedTypo(std::unique_ptr<TypoCorrectionConsumer> TCC,
                                TypoDiagnosticGenerator TDG,
                                TypoRecoveryCallback TRC) {
assert(TCC && "createDelayedTypo requires a valid TypoCorrectionConsumer")(static_cast <bool> (TCC && "createDelayedTypo requires a valid TypoCorrectionConsumer"
) ? void (0) : __assert_fail ("TCC && \"createDelayedTypo requires a valid TypoCorrectionConsumer\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 5203, __extension__ __PRETTY_FUNCTION__));
auto TE = new (Context) TypoExpr(Context.DependentTy);
auto &State = DelayedTypos[TE];
State.Consumer = std::move(TCC);
State.DiagHandler = std::move(TDG);
State.RecoveryHandler = std::move(TRC);
return TE;
5210}

5212const Sema::TypoExprState &Sema::getTypoExprState(TypoExpr *TE) const {
auto Entry = DelayedTypos.find(TE);
assert(Entry != DelayedTypos.end() &&(static_cast <bool> (Entry != DelayedTypos.end() &&
 "Failed to get the state for a TypoExpr!") ? void (0) : __assert_fail
 ("Entry != DelayedTypos.end() && \"Failed to get the state for a TypoExpr!\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 5215, __extension__ __PRETTY_FUNCTION__))
       "Failed to get the state for a TypoExpr!")(static_cast <bool> (Entry != DelayedTypos.end() &&
 "Failed to get the state for a TypoExpr!") ? void (0) : __assert_fail
 ("Entry != DelayedTypos.end() && \"Failed to get the state for a TypoExpr!\""
, "/build/llvm-toolchain-snapshot-7~svn338205/tools/clang/lib/Sema/SemaLookup.cpp"
, 5215, __extension__ __PRETTY_FUNCTION__));
return Entry->second;
5217}

5219void Sema::clearDelayedTypo(TypoExpr *TE) {
DelayedTypos.erase(TE);
5221}

5223void Sema::ActOnPragmaDump(Scope *S, SourceLocation IILoc, IdentifierInfo *II) {
DeclarationNameInfo Name(II, IILoc);
LookupResult R(*this, Name, LookupAnyName, Sema::NotForRedeclaration);
R.suppressDiagnostics();
R.setHideTags(false);
LookupName(R, S);
R.dump();
5230}

←

/build/llvm-toolchain-snapshot-7~svn338205/include/llvm/ADT/STLExtras.h

→

1//===- llvm/ADT/STLExtras.h - Useful STL related functions ------*- C++ -*-===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file contains some templates that are useful if you are working with the
11// STL at all.
12//
13// No library is required when using these functions.
14//
15//===----------------------------------------------------------------------===//
16 
17#ifndef LLVM_ADT_STLEXTRAS_H
18#define LLVM_ADT_STLEXTRAS_H
19 
20#include "llvm/ADT/Optional.h"
21#include "llvm/ADT/SmallVector.h"
22#include "llvm/ADT/iterator.h"
23#include "llvm/ADT/iterator_range.h"
24#include "llvm/Support/ErrorHandling.h"
25#include <algorithm>
26#include <cassert>
27#include <cstddef>
28#include <cstdint>
29#include <cstdlib>
30#include <functional>
31#include <initializer_list>
32#include <iterator>
33#include <limits>
34#include <memory>
35#include <tuple>
36#include <type_traits>
37#include <utility>
38 
39#ifdef EXPENSIVE_CHECKS
40#include <random> // for std::mt19937
41#endif
42 
43namespace llvm {
44 
45// Only used by compiler if both template types are the same.  Useful when
46// using SFINAE to test for the existence of member functions.
47template <typename T, T> struct SameType;
48 
49namespace detail {
50 
51template <typename RangeT>
52using IterOfRange = decltype(std::begin(std::declval<RangeT &>()));
53 
54template <typename RangeT>
55using ValueOfRange = typename std::remove_reference<decltype(
56    *std::begin(std::declval<RangeT &>()))>::type;
57 
58} // end namespace detail
59 
60//===----------------------------------------------------------------------===//
61//     Extra additions to <type_traits>
62//===----------------------------------------------------------------------===//
63 
64template <typename T>
65struct negation : std::integral_constant<bool, !bool(T::value)> {};
66 
67template <typename...> struct conjunction : std::true_type {};
68template <typename B1> struct conjunction<B1> : B1 {};
69template <typename B1, typename... Bn>
70struct conjunction<B1, Bn...>
71    : std::conditional<bool(B1::value), conjunction<Bn...>, B1>::type {};
72 
73//===----------------------------------------------------------------------===//
74//     Extra additions to <functional>
75//===----------------------------------------------------------------------===//
76 
77template <class Ty> struct identity {
78  using argument_type = Ty;
79 
80  Ty &operator()(Ty &self) const {
81    return self;
82  }
83  const Ty &operator()(const Ty &self) const {
84    return self;
85  }
86};
87 
88template <class Ty> struct less_ptr {
89  bool operator()(const Ty* left, const Ty* right) const {
90    return *left < *right;
91  }
92};
93 
94template <class Ty> struct greater_ptr {
95  bool operator()(const Ty* left, const Ty* right) const {
96    return *right < *left;
97  }
98};
99 
100/// An efficient, type-erasing, non-owning reference to a callable. This is
101/// intended for use as the type of a function parameter that is not used
102/// after the function in question returns.
103///
104/// This class does not own the callable, so it is not in general safe to store
105/// a function_ref.
106template<typename Fn> class function_ref;
107 
108template<typename Ret, typename ...Params>
109class function_ref<Ret(Params...)> {
110  Ret (*callback)(intptr_t callable, Params ...params) = nullptr;
111  intptr_t callable;
112 
113  template<typename Callable>
114  static Ret callback_fn(intptr_t callable, Params ...params) {
115    return (*reinterpret_cast<Callable*>(callable))(
116        std::forward<Params>(params)...);
117  }
118 
119public:
120  function_ref() = default;
121  function_ref(std::nullptr_t) {}
122 
123  template <typename Callable>
124  function_ref(Callable &&callable,
125               typename std::enable_if<
126                   !std::is_same<typename std::remove_reference<Callable>::type,
127                                 function_ref>::value>::type * = nullptr)
128      : callback(callback_fn<typename std::remove_reference<Callable>::type>),
129        callable(reinterpret_cast<intptr_t>(&callable)) {}
130 
131  Ret operator()(Params ...params) const {
132    return callback(callable, std::forward<Params>(params)...);
133  }
134 
135  operator bool() const { return callback; }
136};
137 
138// deleter - Very very very simple method that is used to invoke operator
139// delete on something.  It is used like this:
140//
141//   for_each(V.begin(), B.end(), deleter<Interval>);
142template <class T>
143inline void deleter(T *Ptr) {
144  delete Ptr;
145}
146 
147//===----------------------------------------------------------------------===//
148//     Extra additions to <iterator>
149//===----------------------------------------------------------------------===//
150 
151namespace adl_detail {
152 
153using std::begin;
154 
155template <typename ContainerTy>
156auto adl_begin(ContainerTy &&container)
157    -> decltype(begin(std::forward<ContainerTy>(container))) {
158  return begin(std::forward<ContainerTy>(container));
159}
160 
161using std::end;
162 
163template <typename ContainerTy>
164auto adl_end(ContainerTy &&container)
165    -> decltype(end(std::forward<ContainerTy>(container))) {
166  return end(std::forward<ContainerTy>(container));
167}
168 
169using std::swap;
170 
171template <typename T>
172void adl_swap(T &&lhs, T &&rhs) noexcept(noexcept(swap(std::declval<T>(),
173                                                       std::declval<T>()))) {
174  swap(std::forward<T>(lhs), std::forward<T>(rhs));
175}
176 
177} // end namespace adl_detail
178 
179template <typename ContainerTy>
180auto adl_begin(ContainerTy &&container)
181    -> decltype(adl_detail::adl_begin(std::forward<ContainerTy>(container))) {
182  return adl_detail::adl_begin(std::forward<ContainerTy>(container));
183}
184 
185template <typename ContainerTy>
186auto adl_end(ContainerTy &&container)
187    -> decltype(adl_detail::adl_end(std::forward<ContainerTy>(container))) {
188  return adl_detail::adl_end(std::forward<ContainerTy>(container));
189}
190 
191template <typename T>
192void adl_swap(T &&lhs, T &&rhs) noexcept(
193    noexcept(adl_detail::adl_swap(std::declval<T>(), std::declval<T>()))) {
194  adl_detail::adl_swap(std::forward<T>(lhs), std::forward<T>(rhs));
195}
196 
197// mapped_iterator - This is a simple iterator adapter that causes a function to
198// be applied whenever operator* is invoked on the iterator.
199 
200template <typename ItTy, typename FuncTy,
201          typename FuncReturnTy =
202            decltype(std::declval<FuncTy>()(*std::declval<ItTy>()))>
203class mapped_iterator
204    : public iterator_adaptor_base<
205             mapped_iterator<ItTy, FuncTy>, ItTy,
206             typename std::iterator_traits<ItTy>::iterator_category,
207             typename std::remove_reference<FuncReturnTy>::type> {
208public:
209  mapped_iterator(ItTy U, FuncTy F)
210    : mapped_iterator::iterator_adaptor_base(std::move(U)), F(std::move(F)) {}
211 
212  ItTy getCurrent() { return this->I; }
213 
214  FuncReturnTy operator*() { return F(*this->I); }
215 
216private:
217  FuncTy F;
218};
219 
220// map_iterator - Provide a convenient way to create mapped_iterators, just like
221// make_pair is useful for creating pairs...
222template <class ItTy, class FuncTy>
223inline mapped_iterator<ItTy, FuncTy> map_iterator(ItTy I, FuncTy F) {
224  return mapped_iterator<ItTy, FuncTy>(std::move(I), std::move(F));
225}
226 
227/// Helper to determine if type T has a member called rbegin().
228template <typename Ty> class has_rbegin_impl {
229  using yes = char[1];
230  using no = char[2];
231 
232  template <typename Inner>
233  static yes& test(Inner *I, decltype(I->rbegin()) * = nullptr);
234 
235  template <typename>
236  static no& test(...);
237 
238public:
239  static const bool value = sizeof(test<Ty>(nullptr)) == sizeof(yes);
240};
241 
242/// Metafunction to determine if T& or T has a member called rbegin().
243template <typename Ty>
244struct has_rbegin : has_rbegin_impl<typename std::remove_reference<Ty>::type> {
245};
246 
247// Returns an iterator_range over the given container which iterates in reverse.
248// Note that the container must have rbegin()/rend() methods for this to work.
249template <typename ContainerTy>
250auto reverse(ContainerTy &&C,
251             typename std::enable_if<has_rbegin<ContainerTy>::value>::type * =
252                 nullptr) -> decltype(make_range(C.rbegin(), C.rend())) {
253  return make_range(C.rbegin(), C.rend());
254}
255 
256// Returns a std::reverse_iterator wrapped around the given iterator.
257template <typename IteratorTy>
258std::reverse_iterator<IteratorTy> make_reverse_iterator(IteratorTy It) {
259  return std::reverse_iterator<IteratorTy>(It);
260}
261 
262// Returns an iterator_range over the given container which iterates in reverse.
263// Note that the container must have begin()/end() methods which return
264// bidirectional iterators for this to work.
265template <typename ContainerTy>
266auto reverse(
267    ContainerTy &&C,
268    typename std::enable_if<!has_rbegin<ContainerTy>::value>::type * = nullptr)
269    -> decltype(make_range(llvm::make_reverse_iterator(std::end(C)),
270                           llvm::make_reverse_iterator(std::begin(C)))) {
271  return make_range(llvm::make_reverse_iterator(std::end(C)),
272                    llvm::make_reverse_iterator(std::begin(C)));
273}
274 
275/// An iterator adaptor that filters the elements of given inner iterators.
276///
277/// The predicate parameter should be a callable object that accepts the wrapped
278/// iterator's reference type and returns a bool. When incrementing or
279/// decrementing the iterator, it will call the predicate on each element and
280/// skip any where it returns false.
281///
282/// \code
283///   int A[] = { 1, 2, 3, 4 };
284///   auto R = make_filter_range(A, [](int N) { return N % 2 == 1; });
285///   // R contains { 1, 3 }.
286/// \endcode
287///
288/// Note: filter_iterator_base implements support for forward iteration.
289/// filter_iterator_impl exists to provide support for bidirectional iteration,
290/// conditional on whether the wrapped iterator supports it.
291template <typename WrappedIteratorT, typename PredicateT, typename IterTag>
292class filter_iterator_base
293    : public iterator_adaptor_base<
294          filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
295          WrappedIteratorT,
296          typename std::common_type<
297              IterTag, typename std::iterator_traits<
298                           WrappedIteratorT>::iterator_category>::type> {
299  using BaseT = iterator_adaptor_base<
300      filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>,
301      WrappedIteratorT,
302      typename std::common_type<
303          IterTag, typename std::iterator_traits<
304                       WrappedIteratorT>::iterator_category>::type>;
305 
306protected:
307  WrappedIteratorT End;
308  PredicateT Pred;
309 
310  void findNextValid() {
311    while (this->I != End && !Pred(*this->I))
312      BaseT::operator++();
313  }
314 
315  // Construct the iterator. The begin iterator needs to know where the end
316  // is, so that it can properly stop when it gets there. The end iterator only
317  // needs the predicate to support bidirectional iteration.
318  filter_iterator_base(WrappedIteratorT Begin, WrappedIteratorT End,
319                       PredicateT Pred)
320      : BaseT(Begin), End(End), Pred(Pred) {
321    findNextValid();
322  }
323 
324public:
325  using BaseT::operator++;
326 
327  filter_iterator_base &operator++() {
328    BaseT::operator++();
329    findNextValid();
330    return *this;
331  }
332};
333 
334/// Specialization of filter_iterator_base for forward iteration only.
335template <typename WrappedIteratorT, typename PredicateT,
336          typename IterTag = std::forward_iterator_tag>
337class filter_iterator_impl
338    : public filter_iterator_base<WrappedIteratorT, PredicateT, IterTag> {
339  using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT, IterTag>;
340 
341public:
342  filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
343                       PredicateT Pred)
344      : BaseT(Begin, End, Pred) {}
345};
346 
347/// Specialization of filter_iterator_base for bidirectional iteration.
348template <typename WrappedIteratorT, typename PredicateT>
349class filter_iterator_impl<WrappedIteratorT, PredicateT,
350                           std::bidirectional_iterator_tag>
351    : public filter_iterator_base<WrappedIteratorT, PredicateT,
352                                  std::bidirectional_iterator_tag> {
353  using BaseT = filter_iterator_base<WrappedIteratorT, PredicateT,
354                                     std::bidirectional_iterator_tag>;
355  void findPrevValid() {
356    while (!this->Pred(*this->I))
357      BaseT::operator--();
358  }
359 
360public:
361  using BaseT::operator--;
362 
363  filter_iterator_impl(WrappedIteratorT Begin, WrappedIteratorT End,
364                       PredicateT Pred)
365      : BaseT(Begin, End, Pred) {}
366 
367  filter_iterator_impl &operator--() {
368    BaseT::operator--();
369    findPrevValid();
370    return *this;
371  }
372};
373 
374namespace detail {
375 
376template <bool is_bidirectional> struct fwd_or_bidi_tag_impl {
377  using type = std::forward_iterator_tag;
378};
379 
380template <> struct fwd_or_bidi_tag_impl<true> {
381  using type = std::bidirectional_iterator_tag;
382};
383 
384/// Helper which sets its type member to forward_iterator_tag if the category
385/// of \p IterT does not derive from bidirectional_iterator_tag, and to
386/// bidirectional_iterator_tag otherwise.
387template <typename IterT> struct fwd_or_bidi_tag {
388  using type = typename fwd_or_bidi_tag_impl<std::is_base_of<
389      std::bidirectional_iterator_tag,
390      typename std::iterator_traits<IterT>::iterator_category>::value>::type;
391};
392 
393} // namespace detail
394 
395/// Defines filter_iterator to a suitable specialization of
396/// filter_iterator_impl, based on the underlying iterator's category.
397template <typename WrappedIteratorT, typename PredicateT>
398using filter_iterator = filter_iterator_impl<
399    WrappedIteratorT, PredicateT,
400    typename detail::fwd_or_bidi_tag<WrappedIteratorT>::type>;
401 
402/// Convenience function that takes a range of elements and a predicate,
403/// and return a new filter_iterator range.
404///
405/// FIXME: Currently if RangeT && is a rvalue reference to a temporary, the
406/// lifetime of that temporary is not kept by the returned range object, and the
407/// temporary is going to be dropped on the floor after the make_iterator_range
408/// full expression that contains this function call.
409template <typename RangeT, typename PredicateT>
410iterator_range<filter_iterator<detail::IterOfRange<RangeT>, PredicateT>>
411make_filter_range(RangeT &&Range, PredicateT Pred) {
412  using FilterIteratorT =
413      filter_iterator<detail::IterOfRange<RangeT>, PredicateT>;
414  return make_range(
415      FilterIteratorT(std::begin(std::forward<RangeT>(Range)),
416                      std::end(std::forward<RangeT>(Range)), Pred),
417      FilterIteratorT(std::end(std::forward<RangeT>(Range)),
418                      std::end(std::forward<RangeT>(Range)), Pred));
419}
420 
421// forward declarations required by zip_shortest/zip_first
422template <typename R, typename UnaryPredicate>
423bool all_of(R &&range, UnaryPredicate P);
424 
425template <size_t... I> struct index_sequence;
426 
427template <class... Ts> struct index_sequence_for;
428 
429namespace detail {
430 
431using std::declval;
432 
433// We have to alias this since inlining the actual type at the usage site
434// in the parameter list of iterator_facade_base<> below ICEs MSVC 2017.
435template<typename... Iters> struct ZipTupleType {
436  using type = std::tuple<decltype(*declval<Iters>())...>;
437};
438 
439template <typename ZipType, typename... Iters>
440using zip_traits = iterator_facade_base<
441    ZipType, typename std::common_type<std::bidirectional_iterator_tag,
442                                       typename std::iterator_traits<
443                                           Iters>::iterator_category...>::type,
444    // ^ TODO: Implement random access methods.
445    typename ZipTupleType<Iters...>::type,
446    typename std::iterator_traits<typename std::tuple_element<
447        0, std::tuple<Iters...>>::type>::difference_type,
448    // ^ FIXME: This follows boost::make_zip_iterator's assumption that all
449    // inner iterators have the same difference_type. It would fail if, for
450    // instance, the second field's difference_type were non-numeric while the
451    // first is.
452    typename ZipTupleType<Iters...>::type *,
453    typename ZipTupleType<Iters...>::type>;
454 
455template <typename ZipType, typename... Iters>
456struct zip_common : public zip_traits<ZipType, Iters...> {
457  using Base = zip_traits<ZipType, Iters...>;
458  using value_type = typename Base::value_type;
459 
460  std::tuple<Iters...> iterators;
461 
462protected:
463  template <size_t... Ns> value_type deref(index_sequence<Ns...>) const {
464    return value_type(*std::get<Ns>(iterators)...);
465  }
466 
467  template <size_t... Ns>
468  decltype(iterators) tup_inc(index_sequence<Ns...>) const {
469    return std::tuple<Iters...>(std::next(std::get<Ns>(iterators))...);
470  }
471 
472  template <size_t... Ns>
473  decltype(iterators) tup_dec(index_sequence<Ns...>) const {
474    return std::tuple<Iters...>(std::prev(std::get<Ns>(iterators))...);
475  }
476 
477public:
478  zip_common(Iters &&... ts) : iterators(std::forward<Iters>(ts)...) {}
479 
480  value_type operator*() { return deref(index_sequence_for<Iters...>{}); }
481 
482  const value_type operator*() const {
483    return deref(index_sequence_for<Iters...>{});
484  }
485 
486  ZipType &operator++() {
487    iterators = tup_inc(index_sequence_for<Iters...>{});
488    return *reinterpret_cast<ZipType *>(this);
489  }
490 
491  ZipType &operator--() {
492    static_assert(Base::IsBidirectional,
493                  "All inner iterators must be at least bidirectional.");
494    iterators = tup_dec(index_sequence_for<Iters...>{});
495    return *reinterpret_cast<ZipType *>(this);
496  }
497};
498 
499template <typename... Iters>
500struct zip_first : public zip_common<zip_first<Iters...>, Iters...> {
501  using Base = zip_common<zip_first<Iters...>, Iters...>;
502 
503  bool operator==(const zip_first<Iters...> &other) const {
504    return std::get<0>(this->iterators) == std::get<0>(other.iterators);
505  }
506 
507  zip_first(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
508};
509 
510template <typename... Iters>
511class zip_shortest : public zip_common<zip_shortest<Iters...>, Iters...> {
512  template <size_t... Ns>
513  bool test(const zip_shortest<Iters...> &other, index_sequence<Ns...>) const {
514    return all_of(std::initializer_list<bool>{std::get<Ns>(this->iterators) !=
515                                              std::get<Ns>(other.iterators)...},
516                  identity<bool>{});
517  }
518 
519public:
520  using Base = zip_common<zip_shortest<Iters...>, Iters...>;
521 
522  zip_shortest(Iters &&... ts) : Base(std::forward<Iters>(ts)...) {}
523 
524  bool operator==(const zip_shortest<Iters...> &other) const {
525    return !test(other, index_sequence_for<Iters...>{});
526  }
527};
528 
529template <template <typename...> class ItType, typename... Args> class zippy {
530public:
531  using iterator = ItType<decltype(std::begin(std::declval<Args>()))...>;
532  using iterator_category = typename iterator::iterator_category;
533  using value_type = typename iterator::value_type;
534  using difference_type = typename iterator::difference_type;
535  using pointer = typename iterator::pointer;
536  using reference = typename iterator::reference;
537 
538private:
539  std::tuple<Args...> ts;
540 
541  template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) const {
542    return iterator(std::begin(std::get<Ns>(ts))...);
543  }
544  template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) const {
545    return iterator(std::end(std::get<Ns>(ts))...);
546  }
547 
548public:
549  zippy(Args &&... ts_) : ts(std::forward<Args>(ts_)...) {}
550 
551  iterator begin() const { return begin_impl(index_sequence_for<Args...>{}); }
552  iterator end() const { return end_impl(index_sequence_for<Args...>{}); }
553};
554 
555} // end namespace detail
556 
557/// zip iterator for two or more iteratable types.
558template <typename T, typename U, typename... Args>
559detail::zippy<detail::zip_shortest, T, U, Args...> zip(T &&t, U &&u,
560                                                       Args &&... args) {
561  return detail::zippy<detail::zip_shortest, T, U, Args...>(
562      std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
563}
564 
565/// zip iterator that, for the sake of efficiency, assumes the first iteratee to
566/// be the shortest.
567template <typename T, typename U, typename... Args>
568detail::zippy<detail::zip_first, T, U, Args...> zip_first(T &&t, U &&u,
569                                                          Args &&... args) {
570  return detail::zippy<detail::zip_first, T, U, Args...>(
571      std::forward<T>(t), std::forward<U>(u), std::forward<Args>(args)...);
572}
573 
574/// Iterator wrapper that concatenates sequences together.
575///
576/// This can concatenate different iterators, even with different types, into
577/// a single iterator provided the value types of all the concatenated
578/// iterators expose `reference` and `pointer` types that can be converted to
579/// `ValueT &` and `ValueT *` respectively. It doesn't support more
580/// interesting/customized pointer or reference types.
581///
582/// Currently this only supports forward or higher iterator categories as
583/// inputs and always exposes a forward iterator interface.
584template <typename ValueT, typename... IterTs>
585class concat_iterator
586    : public iterator_facade_base<concat_iterator<ValueT, IterTs...>,
587                                  std::forward_iterator_tag, ValueT> {
588  using BaseT = typename concat_iterator::iterator_facade_base;
589 
590  /// We store both the current and end iterators for each concatenated
591  /// sequence in a tuple of pairs.
592  ///
593  /// Note that something like iterator_range seems nice at first here, but the
594  /// range properties are of little benefit and end up getting in the way
595  /// because we need to do mutation on the current iterators.
596  std::tuple<std::pair<IterTs, IterTs>...> IterPairs;
597 
598  /// Attempts to increment a specific iterator.
599  ///
600  /// Returns true if it was able to increment the iterator. Returns false if
601  /// the iterator is already at the end iterator.
602  template <size_t Index> bool incrementHelper() {
603    auto &IterPair = std::get<Index>(IterPairs);
604    if (IterPair.first == IterPair.second)
605      return false;
606 
607    ++IterPair.first;
608    return true;
609  }
610 
611  /// Increments the first non-end iterator.
612  ///
613  /// It is an error to call this with all iterators at the end.
614  template <size_t... Ns> void increment(index_sequence<Ns...>) {
615    // Build a sequence of functions to increment each iterator if possible.
616    bool (concat_iterator::*IncrementHelperFns[])() = {
617        &concat_iterator::incrementHelper<Ns>...};
618 
619    // Loop over them, and stop as soon as we succeed at incrementing one.
620    for (auto &IncrementHelperFn : IncrementHelperFns)
621      if ((this->*IncrementHelperFn)())
622        return;
623 
624    llvm_unreachable("Attempted to increment an end concat iterator!")::llvm::llvm_unreachable_internal("Attempted to increment an end concat iterator!"
, "/build/llvm-toolchain-snapshot-7~svn338205/include/llvm/ADT/STLExtras.h"
, 624);
625  }
626 
627  /// Returns null if the specified iterator is at the end. Otherwise,
628  /// dereferences the iterator and returns the address of the resulting
629  /// reference.
630  template <size_t Index> ValueT *getHelper() const {
631    auto &IterPair = std::get<Index>(IterPairs);
632    if (IterPair.first == IterPair.second)
633      return nullptr;
634 
635    return &*IterPair.first;
636  }
637 
638  /// Finds the first non-end iterator, dereferences, and returns the resulting
639  /// reference.
640  ///
641  /// It is an error to call this with all iterators at the end.
642  template <size_t... Ns> ValueT &get(index_sequence<Ns...>) const {
643    // Build a sequence of functions to get from iterator if possible.
644    ValueT *(concat_iterator::*GetHelperFns[])() const = {
645        &concat_iterator::getHelper<Ns>...};
646 
647    // Loop over them, and return the first result we find.
648    for (auto &GetHelperFn : GetHelperFns)
649      if (ValueT *P = (this->*GetHelperFn)())
650        return *P;
651 
652    llvm_unreachable("Attempted to get a pointer from an end concat iterator!")::llvm::llvm_unreachable_internal("Attempted to get a pointer from an end concat iterator!"
, "/build/llvm-toolchain-snapshot-7~svn338205/include/llvm/ADT/STLExtras.h"
, 652);
653  }
654 
655public:
656  /// Constructs an iterator from a squence of ranges.
657  ///
658  /// We need the full range to know how to switch between each of the
659  /// iterators.
660  template <typename... RangeTs>
661  explicit concat_iterator(RangeTs &&... Ranges)
662      : IterPairs({std::begin(Ranges), std::end(Ranges)}...) {}
663 
664  using BaseT::operator++;
665 
666  concat_iterator &operator++() {
667    increment(index_sequence_for<IterTs...>());
668    return *this;
669  }
670 
671  ValueT &operator*() const { return get(index_sequence_for<IterTs...>()); }
672 
673  bool operator==(const concat_iterator &RHS) const {
674    return IterPairs == RHS.IterPairs;
675  }
676};
677 
678namespace detail {
679 
680/// Helper to store a sequence of ranges being concatenated and access them.
681///
682/// This is designed to facilitate providing actual storage when temporaries
683/// are passed into the constructor such that we can use it as part of range
684/// based for loops.
685template <typename ValueT, typename... RangeTs> class concat_range {
686public:
687  using iterator =
688      concat_iterator<ValueT,
689                      decltype(std::begin(std::declval<RangeTs &>()))...>;
690 
691private:
692  std::tuple<RangeTs...> Ranges;
693 
694  template <size_t... Ns> iterator begin_impl(index_sequence<Ns...>) {
695    return iterator(std::get<Ns>(Ranges)...);
696  }
697  template <size_t... Ns> iterator end_impl(index_sequence<Ns...>) {
698    return iterator(make_range(std::end(std::get<Ns>(Ranges)),
699                               std::end(std::get<Ns>(Ranges)))...);
700  }
701 
702public:
703  concat_range(RangeTs &&... Ranges)
704      : Ranges(std::forward<RangeTs>(Ranges)...) {}
705 
706  iterator begin() { return begin_impl(index_sequence_for<RangeTs...>{}); }
707  iterator end() { return end_impl(index_sequence_for<RangeTs...>{}); }
708};
709 
710} // end namespace detail
711 
712/// Concatenated range across two or more ranges.
713///
714/// The desired value type must be explicitly specified.
715template <typename ValueT, typename... RangeTs>
716detail::concat_range<ValueT, RangeTs...> concat(RangeTs &&... Ranges) {
717  static_assert(sizeof...(RangeTs) > 1,
718                "Need more than one range to concatenate!");
719  return detail::concat_range<ValueT, RangeTs...>(
720      std::forward<RangeTs>(Ranges)...);
721}
722 
723//===----------------------------------------------------------------------===//
724//     Extra additions to <utility>
725//===----------------------------------------------------------------------===//
726 
727/// Function object to check whether the first component of a std::pair
728/// compares less than the first component of another std::pair.
729struct less_first {
730  template <typename T> bool operator()(const T &lhs, const T &rhs) const {
731    return lhs.first < rhs.first;
732  }
733};
734 
735/// Function object to check whether the second component of a std::pair
736/// compares less than the second component of another std::pair.
737struct less_second {
738  template <typename T> bool operator()(const T &lhs, const T &rhs) const {
739    return lhs.second < rhs.second;
740  }
741};
742 
743// A subset of N3658. More stuff can be added as-needed.
744 
745/// Represents a compile-time sequence of integers.
746template <class T, T... I> struct integer_sequence {
747  using value_type = T;
748 
749  static constexpr size_t size() { return sizeof...(I); }
750};
751 
752/// Alias for the common case of a sequence of size_ts.
753template <size_t... I>
754struct index_sequence : integer_sequence<std::size_t, I...> {};
755 
756template <std::size_t N, std::size_t... I>
757struct build_index_impl : build_index_impl<N - 1, N - 1, I...> {};
758template <std::size_t... I>
759struct build_index_impl<0, I...> : index_sequence<I...> {};
760 
761/// Creates a compile-time integer sequence for a parameter pack.
762template <class... Ts>
763struct index_sequence_for : build_index_impl<sizeof...(Ts)> {};
764 
765/// Utility type to build an inheritance chain that makes it easy to rank
766/// overload candidates.
767template <int N> struct rank : rank<N - 1> {};
768template <> struct rank<0> {};
769 
770/// traits class for checking whether type T is one of any of the given
771/// types in the variadic list.
772template <typename T, typename... Ts> struct is_one_of {
773  static const bool value = false;
774};
775 
776template <typename T, typename U, typename... Ts>
777struct is_one_of<T, U, Ts...> {
778  static const bool value =
779      std::is_same<T, U>::value || is_one_of<T, Ts...>::value;
780};
781 
782/// traits class for checking whether type T is a base class for all
783///  the given types in the variadic list.
784template <typename T, typename... Ts> struct are_base_of {
785  static const bool value = true;
786};
787 
788template <typename T, typename U, typename... Ts>
789struct are_base_of<T, U, Ts...> {
790  static const bool value =
791      std::is_base_of<T, U>::value && are_base_of<T, Ts...>::value;
792};
793 
794//===----------------------------------------------------------------------===//
795//     Extra additions for arrays
796//===----------------------------------------------------------------------===//
797 
798/// Find the length of an array.
799template <class T, std::size_t N>
800constexpr inline size_t array_lengthof(T (&)[N]) {
801  return N;
802}
803 
804/// Adapt std::less<T> for array_pod_sort.
805template<typename T>
806inline int array_pod_sort_comparator(const void *P1, const void *P2) {
807  if (std::less<T>()(*reinterpret_cast<const T*>(P1),
808                     *reinterpret_cast<const T*>(P2)))
809    return -1;
810  if (std::less<T>()(*reinterpret_cast<const T*>(P2),
811                     *reinterpret_cast<const T*>(P1)))
812    return 1;
813  return 0;
814}
815 
816/// get_array_pod_sort_comparator - This is an internal helper function used to
817/// get type deduction of T right.
818template<typename T>
819inline int (*get_array_pod_sort_comparator(const T &))
820             (const void*, const void*) {
821  return array_pod_sort_comparator<T>;
822}
823 
824/// array_pod_sort - This sorts an array with the specified start and end
825/// extent.  This is just like std::sort, except that it calls qsort instead of
826/// using an inlined template.  qsort is slightly slower than std::sort, but
827/// most sorts are not performance critical in LLVM and std::sort has to be
828/// template instantiated for each type, leading to significant measured code
829/// bloat.  This function should generally be used instead of std::sort where
830/// possible.
831///
832/// This function assumes that you have simple POD-like types that can be
833/// compared with std::less and can be moved with memcpy.  If this isn't true,
834/// you should use std::sort.
835///
836/// NOTE: If qsort_r were portable, we could allow a custom comparator and
837/// default to std::less.
838template<class IteratorTy>
839inline void array_pod_sort(IteratorTy Start, IteratorTy End) {
840  // Don't inefficiently call qsort with one element or trigger undefined
841  // behavior with an empty sequence.
842  auto NElts = End - Start;
843  if (NElts <= 1) return;
844#ifdef EXPENSIVE_CHECKS
845  std::mt19937 Generator(std::random_device{}());
846  std::shuffle(Start, End, Generator);
847#endif
848  qsort(&*Start, NElts, sizeof(*Start), get_array_pod_sort_comparator(*Start));
849}
850 
851template <class IteratorTy>
852inline void array_pod_sort(
853    IteratorTy Start, IteratorTy End,
854    int (*Compare)(
855        const typename std::iterator_traits<IteratorTy>::value_type *,
856        const typename std::iterator_traits<IteratorTy>::value_type *)) {
857  // Don't inefficiently call qsort with one element or trigger undefined
858  // behavior with an empty sequence.
859  auto NElts = End - Start;
860  if (NElts <= 1) return;
861#ifdef EXPENSIVE_CHECKS
862  std::mt19937 Generator(std::random_device{}());
863  std::shuffle(Start, End, Generator);
864#endif
865  qsort(&*Start, NElts, sizeof(*Start),
866        reinterpret_cast<int (*)(const void *, const void *)>(Compare));
867}
868 
869// Provide wrappers to std::sort which shuffle the elements before sorting
870// to help uncover non-deterministic behavior (PR35135).
871template <typename IteratorTy>
872inline void sort(IteratorTy Start, IteratorTy End) {
873#ifdef EXPENSIVE_CHECKS
874  std::mt19937 Generator(std::random_device{}());
875  std::shuffle(Start, End, Generator);
876#endif
877  std::sort(Start, End);
878}
879 
880template <typename IteratorTy, typename Compare>
881inline void sort(IteratorTy Start, IteratorTy End, Compare Comp) {
882#ifdef EXPENSIVE_CHECKS
883  std::mt19937 Generator(std::random_device{}());
884  std::shuffle(Start, End, Generator);
885#endif
886  std::sort(Start, End, Comp);
887}
888 
889//===----------------------------------------------------------------------===//
890//     Extra additions to <algorithm>
891//===----------------------------------------------------------------------===//
892 
893/// For a container of pointers, deletes the pointers and then clears the
894/// container.
895template<typename Container>
896void DeleteContainerPointers(Container &C) {
897  for (auto V : C)
898    delete V;
899  C.clear();
900}
901 
902/// In a container of pairs (usually a map) whose second element is a pointer,
903/// deletes the second elements and then clears the container.
904template<typename Container>
905void DeleteContainerSeconds(Container &C) {
906  for (auto &V : C)
907    delete V.second;
908  C.clear();
909}
910 
911/// Provide wrappers to std::for_each which take ranges instead of having to
912/// pass begin/end explicitly.
913template <typename R, typename UnaryPredicate>
914UnaryPredicate for_each(R &&Range, UnaryPredicate P) {
915  return std::for_each(adl_begin(Range), adl_end(Range), P);
916}
917 
918/// Provide wrappers to std::all_of which take ranges instead of having to pass
919/// begin/end explicitly.
920template <typename R, typename UnaryPredicate>
921bool all_of(R &&Range, UnaryPredicate P) {
922  return std::all_of(adl_begin(Range), adl_end(Range), P);
923}
924 
925/// Provide wrappers to std::any_of which take ranges instead of having to pass
926/// begin/end explicitly.
927template <typename R, typename UnaryPredicate>
928bool any_of(R &&Range, UnaryPredicate P) {
929  return std::any_of(adl_begin(Range), adl_end(Range), P);
930}
931 
932/// Provide wrappers to std::none_of which take ranges instead of having to pass
933/// begin/end explicitly.
934template <typename R, typename UnaryPredicate>
935bool none_of(R &&Range, UnaryPredicate P) {
936  return std::none_of(adl_begin(Range), adl_end(Range), P);
937}
938 
939/// Provide wrappers to std::find which take ranges instead of having to pass
940/// begin/end explicitly.
941template <typename R, typename T>
942auto find(R &&Range, const T &Val) -> decltype(adl_begin(Range)) {
943  return std::find(adl_begin(Range), adl_end(Range), Val);
944}
945 
946/// Provide wrappers to std::find_if which take ranges instead of having to pass
947/// begin/end explicitly.
948template <typename R, typename UnaryPredicate>
949auto find_if(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
950  return std::find_if(adl_begin(Range), adl_end(Range), P);
951}
952 
953template <typename R, typename UnaryPredicate>
954auto find_if_not(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
955  return std::find_if_not(adl_begin(Range), adl_end(Range), P);
956}
957 
958/// Provide wrappers to std::remove_if which take ranges instead of having to
959/// pass begin/end explicitly.
960template <typename R, typename UnaryPredicate>
961auto remove_if(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
962  return std::remove_if(adl_begin(Range), adl_end(Range), P);
963}
964 
965/// Provide wrappers to std::copy_if which take ranges instead of having to
966/// pass begin/end explicitly.
967template <typename R, typename OutputIt, typename UnaryPredicate>
968OutputIt copy_if(R &&Range, OutputIt Out, UnaryPredicate P) {
969  return std::copy_if(adl_begin(Range), adl_end(Range), Out, P);
970}
971 
972template <typename R, typename OutputIt>
973OutputIt copy(R &&Range, OutputIt Out) {
974  return std::copy(adl_begin(Range), adl_end(Range), Out);
975}
976 
977/// Wrapper function around std::find to detect if an element exists
978/// in a container.
979template <typename R, typename E>
980bool is_contained(R &&Range, const E &Element) {
981  return std::find(adl_begin(Range), adl_end(Range), Element) != adl_end(Range);
982}
983 
984/// Wrapper function around std::count to count the number of times an element
985/// \p Element occurs in the given range \p Range.
986template <typename R, typename E>
987auto count(R &&Range, const E &Element) ->
988    typename std::iterator_traits<decltype(adl_begin(Range))>::difference_type {
989  return std::count(adl_begin(Range), adl_end(Range), Element);
990}
991 
992/// Wrapper function around std::count_if to count the number of times an
993/// element satisfying a given predicate occurs in a range.
994template <typename R, typename UnaryPredicate>
995auto count_if(R &&Range, UnaryPredicate P) ->
996    typename std::iterator_traits<decltype(adl_begin(Range))>::difference_type {
997  return std::count_if(adl_begin(Range), adl_end(Range), P);
998}
999 
1000/// Wrapper function around std::transform to apply a function to a range and
1001/// store the result elsewhere.
1002template <typename R, typename OutputIt, typename UnaryPredicate>
1003OutputIt transform(R &&Range, OutputIt d_first, UnaryPredicate P) {
1004  return std::transform(adl_begin(Range), adl_end(Range), d_first, P);
1005}
1006 
1007/// Provide wrappers to std::partition which take ranges instead of having to
1008/// pass begin/end explicitly.
1009template <typename R, typename UnaryPredicate>
1010auto partition(R &&Range, UnaryPredicate P) -> decltype(adl_begin(Range)) {
1011  return std::partition(adl_begin(Range), adl_end(Range), P);
1012}
1013 
1014/// Provide wrappers to std::lower_bound which take ranges instead of having to
1015/// pass begin/end explicitly.
1016template <typename R, typename ForwardIt>
1017auto lower_bound(R &&Range, ForwardIt I) -> decltype(adl_begin(Range)) {
1018  return std::lower_bound(adl_begin(Range), adl_end(Range), I);
1019}
1020 
1021/// Given a range of type R, iterate the entire range and return a
1022/// SmallVector with elements of the vector.  This is useful, for example,
1023/// when you want to iterate a range and then sort the results.
1024template <unsigned Size, typename R>
1025SmallVector<typename std::remove_const<detail::ValueOfRange<R>>::type, Size>
1026to_vector(R &&Range) {
1027  return {adl_begin(Range), adl_end(Range)};
1028}
1029 
1030/// Provide a container algorithm similar to C++ Library Fundamentals v2's
1031/// `erase_if` which is equivalent to:
1032///
1033///   C.erase(remove_if(C, pred), C.end());
1034///
1035/// This version works for any container with an erase method call accepting
1036/// two iterators.
1037template <typename Container, typename UnaryPredicate>
1038void erase_if(Container &C, UnaryPredicate P) {
1039  C.erase(remove_if(C, P), C.end());
1040}
1041 
1042/// Get the size of a range. This is a wrapper function around std::distance
1043/// which is only enabled when the operation is O(1).
1044template <typename R>
1045auto size(R &&Range, typename std::enable_if<
1046                         std::is_same<typename std::iterator_traits<decltype(
1047                                          Range.begin())>::iterator_category,
1048                                      std::random_access_iterator_tag>::value,
1049                         void>::type * = nullptr)
1050    -> decltype(std::distance(Range.begin(), Range.end())) {
1051  return std::distance(Range.begin(), Range.end());
1052}
1053 
1054//===----------------------------------------------------------------------===//
1055//     Extra additions to <memory>
1056//===----------------------------------------------------------------------===//
1057 
1058// Implement make_unique according to N3656.
1059 
1060/// Constructs a `new T()` with the given args and returns a
1061///        `unique_ptr<T>` which owns the object.
1062///
1063/// Example:
1064///
1065///     auto p = make_unique<int>();
1066///     auto p = make_unique<std::tuple<int, int>>(0, 1);
1067template <class T, class... Args>
1068typename std::enable_if<!std::is_array<T>::value, std::unique_ptr<T>>::type
1069make_unique(Args &&... args) {
1070  return std::unique_ptr<T>(new T(std::forward<Args>(args)...));
19
←
Calling '~unique_ptr'→
24
←
Returning from '~unique_ptr'→
1071}
1072 
1073/// Constructs a `new T[n]` with the given args and returns a
1074///        `unique_ptr<T[]>` which owns the object.
1075///
1076/// \param n size of the new array.
1077///
1078/// Example:
1079///
1080///     auto p = make_unique<int[]>(2); // value-initializes the array with 0's.
1081template <class T>
1082typename std::enable_if<std::is_array<T>::value && std::extent<T>::value == 0,
1083                        std::unique_ptr<T>>::type
1084make_unique(size_t n) {
1085  return std::unique_ptr<T>(new typename std::remove_extent<T>::type[n]());
1086}
1087 
1088/// This function isn't used and is only here to provide better compile errors.
1089template <class T, class... Args>
1090typename std::enable_if<std::extent<T>::value != 0>::type
1091make_unique(Args &&...) = delete;
1092 
1093struct FreeDeleter {
1094  void operator()(void* v) {
1095    ::free(v);
1096  }
1097};
1098 
1099template<typename First, typename Second>
1100struct pair_hash {
1101  size_t operator()(const std::pair<First, Second> &P) const {
1102    return std::hash<First>()(P.first) * 31 + std::hash<Second>()(P.second);
1103  }
1104};
1105 
1106/// A functor like C++14's std::less<void> in its absence.
1107struct less {
1108  template <typename A, typename B> bool operator()(A &&a, B &&b) const {
1109    return std::forward<A>(a) < std::forward<B>(b);
1110  }
1111};
1112 
1113/// A functor like C++14's std::equal<void> in its absence.
1114struct equal {
1115  template <typename A, typename B> bool operator()(A &&a, B &&b) const {
1116    return std::forward<A>(a) == std::forward<B>(b);
1117  }
1118};
1119 
1120/// Binary functor that adapts to any other binary functor after dereferencing
1121/// operands.
1122template <typename T> struct deref {
1123  T func;
1124 
1125  // Could be further improved to cope with non-derivable functors and
1126  // non-binary functors (should be a variadic template member function
1127  // operator()).
1128  template <typename A, typename B>
1129  auto operator()(A &lhs, B &rhs) const -> decltype(func(*lhs, *rhs)) {
1130    assert(lhs)(static_cast <bool> (lhs) ? void (0) : __assert_fail ("lhs"
, "/build/llvm-toolchain-snapshot-7~svn338205/include/llvm/ADT/STLExtras.h"
, 1130, __extension__ __PRETTY_FUNCTION__));
1131    assert(rhs)(static_cast <bool> (rhs) ? void (0) : __assert_fail ("rhs"
, "/build/llvm-toolchain-snapshot-7~svn338205/include/llvm/ADT/STLExtras.h"
, 1131, __extension__ __PRETTY_FUNCTION__));
1132    return func(*lhs, *rhs);
1133  }
1134};
1135 
1136namespace detail {
1137 
1138template <typename R> class enumerator_iter;
1139 
1140template <typename R> struct result_pair {
1141  friend class enumerator_iter<R>;
1142 
1143  result_pair() = default;
1144  result_pair(std::size_t Index, IterOfRange<R> Iter)
1145      : Index(Index), Iter(Iter) {}
1146 
1147  result_pair<R> &operator=(const result_pair<R> &Other) {
1148    Index = Other.Index;
1149    Iter = Other.Iter;
1150    return *this;
1151  }
1152 
1153  std::size_t index() const { return Index; }
1154  const ValueOfRange<R> &value() const { return *Iter; }
1155  ValueOfRange<R> &value() { return *Iter; }
1156 
1157private:
1158  std::size_t Index = std::numeric_limits<std::size_t>::max();
1159  IterOfRange<R> Iter;
1160};
1161 
1162template <typename R>
1163class enumerator_iter
1164    : public iterator_facade_base<
1165          enumerator_iter<R>, std::forward_iterator_tag, result_pair<R>,
1166          typename std::iterator_traits<IterOfRange<R>>::difference_type,
1167          typename std::iterator_traits<IterOfRange<R>>::pointer,
1168          typename std::iterator_traits<IterOfRange<R>>::reference> {
1169  using result_type = result_pair<R>;
1170 
1171public:
1172  explicit enumerator_iter(IterOfRange<R> EndIter)
1173      : Result(std::numeric_limits<size_t>::max(), EndIter) {}
1174 
1175  enumerator_iter(std::size_t Index, IterOfRange<R> Iter)
1176      : Result(Index, Iter) {}
1177 
1178  result_type &operator*() { return Result; }
1179  const result_type &operator*() const { return Result; }
1180 
1181  enumerator_iter<R> &operator++() {
1182    assert(Result.Index != std::numeric_limits<size_t>::max())(static_cast <bool> (Result.Index != std::numeric_limits
<size_t>::max()) ? void (0) : __assert_fail ("Result.Index != std::numeric_limits<size_t>::max()"
, "/build/llvm-toolchain-snapshot-7~svn338205/include/llvm/ADT/STLExtras.h"
, 1182, __extension__ __PRETTY_FUNCTION__));
1183    ++Result.Iter;
1184    ++Result.Index;
1185    return *this;
1186  }
1187 
1188  bool operator==(const enumerator_iter<R> &RHS) const {
1189    // Don't compare indices here, only iterators.  It's possible for an end
1190    // iterator to have different indices depending on whether it was created
1191    // by calling std::end() versus incrementing a valid iterator.
1192    return Result.Iter == RHS.Result.Iter;
1193  }
1194 
1195  enumerator_iter<R> &operator=(const enumerator_iter<R> &Other) {
1196    Result = Other.Result;
1197    return *this;
1198  }
1199 
1200private:
1201  result_type Result;
1202};
1203 
1204template <typename R> class enumerator {
1205public:
1206  explicit enumerator(R &&Range) : TheRange(std::forward<R>(Range)) {}
1207 
1208  enumerator_iter<R> begin() {
1209    return enumerator_iter<R>(0, std::begin(TheRange));
1210  }
1211 
1212  enumerator_iter<R> end() {
1213    return enumerator_iter<R>(std::end(TheRange));
1214  }
1215 
1216private:
1217  R TheRange;
1218};
1219 
1220} // end namespace detail
1221 
1222/// Given an input range, returns a new range whose values are are pair (A,B)
1223/// such that A is the 0-based index of the item in the sequence, and B is
1224/// the value from the original sequence.  Example:
1225///
1226/// std::vector<char> Items = {'A', 'B', 'C', 'D'};
1227/// for (auto X : enumerate(Items)) {
1228///   printf("Item %d - %c\n", X.index(), X.value());
1229/// }
1230///
1231/// Output:
1232///   Item 0 - A
1233///   Item 1 - B
1234///   Item 2 - C
1235///   Item 3 - D
1236///
1237template <typename R> detail::enumerator<R> enumerate(R &&TheRange) {
1238  return detail::enumerator<R>(std::forward<R>(TheRange));
1239}
1240 
1241namespace detail {
1242 
1243template <typename F, typename Tuple, std::size_t... I>
1244auto apply_tuple_impl(F &&f, Tuple &&t, index_sequence<I...>)
1245    -> decltype(std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...)) {
1246  return std::forward<F>(f)(std::get<I>(std::forward<Tuple>(t))...);
1247}
1248 
1249} // end namespace detail
1250 
1251/// Given an input tuple (a1, a2, ..., an), pass the arguments of the
1252/// tuple variadically to f as if by calling f(a1, a2, ..., an) and
1253/// return the result.
1254template <typename F, typename Tuple>
1255auto apply_tuple(F &&f, Tuple &&t) -> decltype(detail::apply_tuple_impl(
1256    std::forward<F>(f), std::forward<Tuple>(t),
1257    build_index_impl<
1258        std::tuple_size<typename std::decay<Tuple>::type>::value>{})) {
1259  using Indices = build_index_impl<
1260      std::tuple_size<typename std::decay<Tuple>::type>::value>;
1261 
1262  return detail::apply_tuple_impl(std::forward<F>(f), std::forward<Tuple>(t),
1263                                  Indices{});
1264}
1265 
1266} // end namespace llvm
1267 
1268#endif // LLVM_ADT_STLEXTRAS_H

←

/usr/lib/gcc/x86_64-linux-gnu/8/../../../../include/c++/8/bits/unique_ptr.h

1// unique_ptr implementation -*- C++ -*-

3// Copyright (C) 2008-2018 Free Software Foundation, Inc.
4//
5// This file is part of the GNU ISO C++ Library.  This library is free
6// software; you can redistribute it and/or modify it under the
7// terms of the GNU General Public License as published by the
8// Free Software Foundation; either version 3, or (at your option)
9// any later version.

11// This library is distributed in the hope that it will be useful,
12// but WITHOUT ANY WARRANTY; without even the implied warranty of
13// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14// GNU General Public License for more details.

16// Under Section 7 of GPL version 3, you are granted additional
17// permissions described in the GCC Runtime Library Exception, version
18// 3.1, as published by the Free Software Foundation.

20// You should have received a copy of the GNU General Public License and
21// a copy of the GCC Runtime Library Exception along with this program;
22// see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
23// <http://www.gnu.org/licenses/>.

25/** @file bits/unique_ptr.h
*  This is an internal header file, included by other library headers.
*  Do not attempt to use it directly. @headername{memory}
*/

30#ifndef _UNIQUE_PTR_H1
31#define _UNIQUE_PTR_H1 1

33#include <bits/c++config.h>
34#include <debug/assertions.h>
35#include <type_traits>
36#include <utility>
37#include <tuple>
38#include <bits/stl_function.h>
39#include <bits/functional_hash.h>

41namespace std _GLIBCXX_VISIBILITY(default)__attribute__ ((__visibility__ ("default")))
42{
43_GLIBCXX_BEGIN_NAMESPACE_VERSION

/**
 * @addtogroup pointer_abstractions
 * @{
 */

50#if _GLIBCXX_USE_DEPRECATED1
51#pragma GCC diagnostic push
52#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
template<typename> class auto_ptr;
54#pragma GCC diagnostic pop
55#endif

/// Primary template of default_delete, used by unique_ptr
template<typename _Tp>
  struct default_delete
  {
    /// Default constructor
    constexpr default_delete() noexcept = default;

    /** @brief Converting constructor.
     *
     * Allows conversion from a deleter for arrays of another type, @p _Up,
     * only if @p _Up* is convertible to @p _Tp*.
     */
    template<typename _Up, typename = typename
      enable_if<is_convertible<_Up*, _Tp*>::value>::type>
      default_delete(const default_delete<_Up>&) noexcept { }

    /// Calls @c delete @p __ptr
    void
    operator()(_Tp* __ptr) const
    {
static_assert(!is_void<_Tp>::value,
      "can't delete pointer to incomplete type");
static_assert(sizeof(_Tp)>0,
      "can't delete pointer to incomplete type");
delete __ptr;
22
←
Memory is released→
    }
  };

// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 740 - omit specialization for array objects with a compile time length
/// Specialization for arrays, default_delete.
template<typename _Tp>
  struct default_delete<_Tp[]>
  {
  public:
    /// Default constructor
    constexpr default_delete() noexcept = default;

    /** @brief Converting constructor.
     *
     * Allows conversion from a deleter for arrays of another type, such as
     * a const-qualified version of @p _Tp.
     *
     * Conversions from types derived from @c _Tp are not allowed because
     * it is unsafe to @c delete[] an array of derived types through a
     * pointer to the base type.
     */
    template<typename _Up, typename = typename
      enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value>::type>
      default_delete(const default_delete<_Up[]>&) noexcept { }

    /// Calls @c delete[] @p __ptr
    template<typename _Up>
    typename enable_if<is_convertible<_Up(*)[], _Tp(*)[]>::value>::type
operator()(_Up* __ptr) const
    {
static_assert(sizeof(_Tp)>0,
      "can't delete pointer to incomplete type");
delete [] __ptr;
    }
  };

template <typename _Tp, typename _Dp>
  class __uniq_ptr_impl
  {
    template <typename _Up, typename _Ep, typename = void>
struct _Ptr
{
 using type = _Up*;
};

    template <typename _Up, typename _Ep>
struct
_Ptr<_Up, _Ep, __void_t<typename remove_reference<_Ep>::type::pointer>>
{
 using type = typename remove_reference<_Ep>::type::pointer;
};

  public:
    using _DeleterConstraint = enable_if<
      __and_<__not_<is_pointer<_Dp>>,
      is_default_constructible<_Dp>>::value>;

    using pointer = typename _Ptr<_Tp, _Dp>::type;

    __uniq_ptr_impl() = default;
    __uniq_ptr_impl(pointer __p) : _M_t() { _M_ptr() = __p; }

    template<typename _Del>
    __uniq_ptr_impl(pointer __p, _Del&& __d)
: _M_t(__p, std::forward<_Del>(__d)) { }

    pointer&   _M_ptr() { return std::get<0>(_M_t); }
    pointer    _M_ptr() const { return std::get<0>(_M_t); }
    _Dp&       _M_deleter() { return std::get<1>(_M_t); }
    const _Dp& _M_deleter() const { return std::get<1>(_M_t); }

  private:
    tuple<pointer, _Dp> _M_t;
  };

/// 20.7.1.2 unique_ptr for single objects.
template <typename _Tp, typename _Dp = default_delete<_Tp>>
  class unique_ptr
  {
    template <class _Up>
    using _DeleterConstraint =
typename __uniq_ptr_impl<_Tp, _Up>::_DeleterConstraint::type;

    __uniq_ptr_impl<_Tp, _Dp> _M_t;

  public:
    using pointer	  = typename __uniq_ptr_impl<_Tp, _Dp>::pointer;
    using element_type  = _Tp;
    using deleter_type  = _Dp;

    // helper template for detecting a safe conversion from another
    // unique_ptr
    template<typename _Up, typename _Ep>
using __safe_conversion_up = __and_<
       is_convertible<typename unique_ptr<_Up, _Ep>::pointer, pointer>,
              __not_<is_array<_Up>>,
              __or_<__and_<is_reference<deleter_type>,
                           is_same<deleter_type, _Ep>>,
                    __and_<__not_<is_reference<deleter_type>>,
                           is_convertible<_Ep, deleter_type>>
              >
            >;

    // Constructors.

    /// Default constructor, creates a unique_ptr that owns nothing.
    template <typename _Up = _Dp,
typename = _DeleterConstraint<_Up>>
constexpr unique_ptr() noexcept
: _M_t()
      { }

    /** Takes ownership of a pointer.
     *
     * @param __p  A pointer to an object of @c element_type
     *
     * The deleter will be value-initialized.
     */
    template <typename _Up = _Dp,
typename = _DeleterConstraint<_Up>>
explicit
unique_ptr(pointer __p) noexcept
: _M_t(__p)
      { }

    /** Takes ownership of a pointer.
     *
     * @param __p  A pointer to an object of @c element_type
     * @param __d  A reference to a deleter.
     *
     * The deleter will be initialized with @p __d
     */
    unique_ptr(pointer __p,
 typename conditional<is_reference<deleter_type>::value,
   deleter_type, const deleter_type&>::type __d) noexcept
    : _M_t(__p, __d) { }

    /** Takes ownership of a pointer.
     *
     * @param __p  A pointer to an object of @c element_type
     * @param __d  An rvalue reference to a deleter.
     *
     * The deleter will be initialized with @p std::move(__d)
     */
    unique_ptr(pointer __p,
 typename remove_reference<deleter_type>::type&& __d) noexcept
    : _M_t(std::move(__p), std::move(__d))
    { static_assert(!std::is_reference<deleter_type>::value,
      "rvalue deleter bound to reference"); }

    /// Creates a unique_ptr that owns nothing.
    template <typename _Up = _Dp,
typename = _DeleterConstraint<_Up>>
constexpr unique_ptr(nullptr_t) noexcept : unique_ptr() { }

    // Move constructors.

    /// Move constructor.
    unique_ptr(unique_ptr&& __u) noexcept
    : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { }

    /** @brief Converting constructor from another type
     *
     * Requires that the pointer owned by @p __u is convertible to the
     * type of pointer owned by this object, @p __u does not own an array,
     * and @p __u has a compatible deleter type.
     */
    template<typename _Up, typename _Ep, typename = _Require<
             __safe_conversion_up<_Up, _Ep>,
      typename conditional<is_reference<_Dp>::value,
		    is_same<_Ep, _Dp>,
		    is_convertible<_Ep, _Dp>>::type>>
unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
: _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
{ }

259#if _GLIBCXX_USE_DEPRECATED1
260#pragma GCC diagnostic push
261#pragma GCC diagnostic ignored "-Wdeprecated-declarations"
    /// Converting constructor from @c auto_ptr
    template<typename _Up, typename = _Require<
      is_convertible<_Up*, _Tp*>, is_same<_Dp, default_delete<_Tp>>>>
unique_ptr(auto_ptr<_Up>&& __u) noexcept;
266#pragma GCC diagnostic pop
267#endif

    /// Destructor, invokes the deleter if the stored pointer is not null.
    ~unique_ptr() noexcept
    {
auto& __ptr = _M_t._M_ptr();
if (__ptr != nullptr)
20
←
Taking true branch→
 get_deleter()(__ptr);
21
←
Calling 'default_delete::operator()'→
23
←
Returning; memory was released via 2nd parameter→
__ptr = pointer();
    }

    // Assignment.

    /** @brief Move assignment operator.
     *
     * @param __u  The object to transfer ownership from.
     *
     * Invokes the deleter first if this object owns a pointer.
     */
    unique_ptr&
    operator=(unique_ptr&& __u) noexcept
    {
reset(__u.release());
get_deleter() = std::forward<deleter_type>(__u.get_deleter());
return *this;
    }

    /** @brief Assignment from another type.
     *
     * @param __u  The object to transfer ownership from, which owns a
     *             convertible pointer to a non-array object.
     *
     * Invokes the deleter first if this object owns a pointer.
     */
    template<typename _Up, typename _Ep>
      typename enable_if< __and_<
        __safe_conversion_up<_Up, _Ep>,
        is_assignable<deleter_type&, _Ep&&>
        >::value,
        unique_ptr&>::type
operator=(unique_ptr<_Up, _Ep>&& __u) noexcept
{
 reset(__u.release());
 get_deleter() = std::forward<_Ep>(__u.get_deleter());
 return *this;
}

    /// Reset the %unique_ptr to empty, invoking the deleter if necessary.
    unique_ptr&
    operator=(nullptr_t) noexcept
    {
reset();
return *this;
    }

    // Observers.

    /// Dereference the stored pointer.
    typename add_lvalue_reference<element_type>::type
    operator*() const
    {
__glibcxx_assert(get() != pointer());
return *get();
    }

    /// Return the stored pointer.
    pointer
    operator->() const noexcept
    {
_GLIBCXX_DEBUG_PEDASSERT(get() != pointer());
return get();
    }

    /// Return the stored pointer.
    pointer
    get() const noexcept
    { return _M_t._M_ptr(); }

    /// Return a reference to the stored deleter.
    deleter_type&
    get_deleter() noexcept
    { return _M_t._M_deleter(); }

    /// Return a reference to the stored deleter.
    const deleter_type&
    get_deleter() const noexcept
    { return _M_t._M_deleter(); }

    /// Return @c true if the stored pointer is not null.
    explicit operator bool() const noexcept
    { return get() == pointer() ? false : true; }

    // Modifiers.

    /// Release ownership of any stored pointer.
    pointer
    release() noexcept
    {
pointer __p = get();
_M_t._M_ptr() = pointer();
return __p;
    }

    /** @brief Replace the stored pointer.
     *
     * @param __p  The new pointer to store.
     *
     * The deleter will be invoked if a pointer is already owned.
     */
    void
    reset(pointer __p = pointer()) noexcept
    {
using std::swap;
swap(_M_t._M_ptr(), __p);
if (__p != pointer())
 get_deleter()(__p);
    }

    /// Exchange the pointer and deleter with another object.
    void
    swap(unique_ptr& __u) noexcept
    {
using std::swap;
swap(_M_t, __u._M_t);
    }

    // Disable copy from lvalue.
    unique_ptr(const unique_ptr&) = delete;
    unique_ptr& operator=(const unique_ptr&) = delete;
};

/// 20.7.1.3 unique_ptr for array objects with a runtime length
// [unique.ptr.runtime]
// _GLIBCXX_RESOLVE_LIB_DEFECTS
// DR 740 - omit specialization for array objects with a compile time length
template<typename _Tp, typename _Dp>
  class unique_ptr<_Tp[], _Dp>
  {
    template <typename _Up>
    using _DeleterConstraint =
typename __uniq_ptr_impl<_Tp, _Up>::_DeleterConstraint::type;

    __uniq_ptr_impl<_Tp, _Dp> _M_t;

    template<typename _Up>
using __remove_cv = typename remove_cv<_Up>::type;

    // like is_base_of<_Tp, _Up> but false if unqualified types are the same
    template<typename _Up>
using __is_derived_Tp
 = __and_< is_base_of<_Tp, _Up>,
    __not_<is_same<__remove_cv<_Tp>, __remove_cv<_Up>>> >;

  public:
    using pointer	  = typename __uniq_ptr_impl<_Tp, _Dp>::pointer;
    using element_type  = _Tp;
    using deleter_type  = _Dp;

    // helper template for detecting a safe conversion from another
    // unique_ptr
    template<typename _Up, typename _Ep,
             typename _Up_up = unique_ptr<_Up, _Ep>,
      typename _Up_element_type = typename _Up_up::element_type>
using __safe_conversion_up = __and_<
        is_array<_Up>,
        is_same<pointer, element_type*>,
        is_same<typename _Up_up::pointer, _Up_element_type*>,
        is_convertible<_Up_element_type(*)[], element_type(*)[]>,
        __or_<__and_<is_reference<deleter_type>, is_same<deleter_type, _Ep>>,
              __and_<__not_<is_reference<deleter_type>>,
                     is_convertible<_Ep, deleter_type>>>
      >;

    // helper template for detecting a safe conversion from a raw pointer
    template<typename _Up>
      using __safe_conversion_raw = __and_<
        __or_<__or_<is_same<_Up, pointer>,
                    is_same<_Up, nullptr_t>>,
              __and_<is_pointer<_Up>,
                     is_same<pointer, element_type*>,
                     is_convertible<
                       typename remove_pointer<_Up>::type(*)[],
                       element_type(*)[]>
              >
        >
      >;

    // Constructors.

    /// Default constructor, creates a unique_ptr that owns nothing.
    template <typename _Up = _Dp,
typename = _DeleterConstraint<_Up>>
constexpr unique_ptr() noexcept
: _M_t()
      { }

    /** Takes ownership of a pointer.
     *
     * @param __p  A pointer to an array of a type safely convertible
     * to an array of @c element_type
     *
     * The deleter will be value-initialized.
     */
    template<typename _Up,
      typename _Vp = _Dp,
      typename = _DeleterConstraint<_Vp>,
      typename = typename enable_if<
               __safe_conversion_raw<_Up>::value, bool>::type>
explicit
unique_ptr(_Up __p) noexcept
: _M_t(__p)
      { }

    /** Takes ownership of a pointer.
     *
     * @param __p  A pointer to an array of a type safely convertible
     * to an array of @c element_type
     * @param __d  A reference to a deleter.
     *
     * The deleter will be initialized with @p __d
     */
    template<typename _Up,
             typename = typename enable_if<
               __safe_conversion_raw<_Up>::value, bool>::type>
    unique_ptr(_Up __p,
               typename conditional<is_reference<deleter_type>::value,
               deleter_type, const deleter_type&>::type __d) noexcept
    : _M_t(__p, __d) { }

    /** Takes ownership of a pointer.
     *
     * @param __p  A pointer to an array of a type safely convertible
     * to an array of @c element_type
     * @param __d  A reference to a deleter.
     *
     * The deleter will be initialized with @p std::move(__d)
     */
    template<typename _Up,
             typename = typename enable_if<
               __safe_conversion_raw<_Up>::value, bool>::type>
    unique_ptr(_Up __p, typename
 remove_reference<deleter_type>::type&& __d) noexcept
    : _M_t(std::move(__p), std::move(__d))
    { static_assert(!is_reference<deleter_type>::value,
      "rvalue deleter bound to reference"); }

    /// Move constructor.
    unique_ptr(unique_ptr&& __u) noexcept
    : _M_t(__u.release(), std::forward<deleter_type>(__u.get_deleter())) { }

    /// Creates a unique_ptr that owns nothing.
    template <typename _Up = _Dp,
typename = _DeleterConstraint<_Up>>
constexpr unique_ptr(nullptr_t) noexcept : unique_ptr() { }

    template<typename _Up, typename _Ep,
      typename = _Require<__safe_conversion_up<_Up, _Ep>>>
unique_ptr(unique_ptr<_Up, _Ep>&& __u) noexcept
: _M_t(__u.release(), std::forward<_Ep>(__u.get_deleter()))
{ }

    /// Destructor, invokes the deleter if the stored pointer is not null.
    ~unique_ptr()
    {
auto& __ptr = _M_t._M_ptr();
if (__ptr != nullptr)
 get_deleter()(__ptr);
__ptr = pointer();
    }

    // Assignment.

    /** @brief Move assignment operator.
     *
     * @param __u  The object to transfer ownership from.
     *
     * Invokes the deleter first if this object owns a pointer.
     */
    unique_ptr&
    operator=(unique_ptr&& __u) noexcept
    {
reset(__u.release());
get_deleter() = std::forward<deleter_type>(__u.get_deleter());
return *this;
    }

    /** @brief Assignment from another type.
     *
     * @param __u  The object to transfer ownership from, which owns a
     *             convertible pointer to an array object.
     *
     * Invokes the deleter first if this object owns a pointer.
     */
    template<typename _Up, typename _Ep>
typename
enable_if<__and_<__safe_conversion_up<_Up, _Ep>,
                       is_assignable<deleter_type&, _Ep&&>
                >::value,
                unique_ptr&>::type
operator=(unique_ptr<_Up, _Ep>&& __u) noexcept
{
 reset(__u.release());
 get_deleter() = std::forward<_Ep>(__u.get_deleter());
 return *this;
}

    /// Reset the %unique_ptr to empty, invoking the deleter if necessary.
    unique_ptr&
    operator=(nullptr_t) noexcept
    {
reset();
return *this;
    }

    // Observers.

    /// Access an element of owned array.
    typename std::add_lvalue_reference<element_type>::type
    operator[](size_t __i) const
    {
__glibcxx_assert(get() != pointer());
return get()[__i];
    }

    /// Return the stored pointer.
    pointer
    get() const noexcept
    { return _M_t._M_ptr(); }

    /// Return a reference to the stored deleter.
    deleter_type&
    get_deleter() noexcept
    { return _M_t._M_deleter(); }

    /// Return a reference to the stored deleter.
    const deleter_type&
    get_deleter() const noexcept
    { return _M_t._M_deleter(); }

    /// Return @c true if the stored pointer is not null.
    explicit operator bool() const noexcept
    { return get() == pointer() ? false : true; }

    // Modifiers.

    /// Release ownership of any stored pointer.
    pointer
    release() noexcept
    {
pointer __p = get();
_M_t._M_ptr() = pointer();
return __p;
    }

    /** @brief Replace the stored pointer.
     *
     * @param __p  The new pointer to store.
     *
     * The deleter will be invoked if a pointer is already owned.
     */
    template <typename _Up,
              typename = _Require<
                __or_<is_same<_Up, pointer>,
                      __and_<is_same<pointer, element_type*>,
                             is_pointer<_Up>,
                             is_convertible<
                               typename remove_pointer<_Up>::type(*)[],
                               element_type(*)[]
                             >
                      >
                >
             >>
    void
    reset(_Up __p) noexcept
    {
pointer __ptr = __p;
using std::swap;
swap(_M_t._M_ptr(), __ptr);
if (__ptr != nullptr)
 get_deleter()(__ptr);
    }

    void reset(nullptr_t = nullptr) noexcept
    {
      reset(pointer());
    }

    /// Exchange the pointer and deleter with another object.
    void
    swap(unique_ptr& __u) noexcept
    {
using std::swap;
swap(_M_t, __u._M_t);
    }

    // Disable copy from lvalue.
    unique_ptr(const unique_ptr&) = delete;
    unique_ptr& operator=(const unique_ptr&) = delete;
  };

template<typename _Tp, typename _Dp>
  inline
669#if __cplusplus201103L > 201402L || !defined(__STRICT_ANSI__1) // c++1z or gnu++11
  // Constrained free swap overload, see p0185r1
  typename enable_if<__is_swappable<_Dp>::value>::type
672#else
  void
674#endif
  swap(unique_ptr<_Tp, _Dp>& __x,
unique_ptr<_Tp, _Dp>& __y) noexcept
  { __x.swap(__y); }

679#if __cplusplus201103L > 201402L || !defined(__STRICT_ANSI__1) // c++1z or gnu++11
template<typename _Tp, typename _Dp>
  typename enable_if<!__is_swappable<_Dp>::value>::type
  swap(unique_ptr<_Tp, _Dp>&,
unique_ptr<_Tp, _Dp>&) = delete;
684#endif

template<typename _Tp, typename _Dp,
  typename _Up, typename _Ep>
  inline bool
  operator==(const unique_ptr<_Tp, _Dp>& __x,
      const unique_ptr<_Up, _Ep>& __y)
  { return __x.get() == __y.get(); }

template<typename _Tp, typename _Dp>
  inline bool
  operator==(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept
  { return !__x; }

template<typename _Tp, typename _Dp>
  inline bool
  operator==(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept
  { return !__x; }

template<typename _Tp, typename _Dp,
  typename _Up, typename _Ep>
  inline bool
  operator!=(const unique_ptr<_Tp, _Dp>& __x,
      const unique_ptr<_Up, _Ep>& __y)
  { return __x.get() != __y.get(); }

template<typename _Tp, typename _Dp>
  inline bool
  operator!=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t) noexcept
  { return (bool)__x; }

template<typename _Tp, typename _Dp>
  inline bool
  operator!=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x) noexcept
  { return (bool)__x; }

template<typename _Tp, typename _Dp,
  typename _Up, typename _Ep>
  inline bool
  operator<(const unique_ptr<_Tp, _Dp>& __x,
     const unique_ptr<_Up, _Ep>& __y)
  {
    typedef typename
std::common_type<typename unique_ptr<_Tp, _Dp>::pointer,
                typename unique_ptr<_Up, _Ep>::pointer>::type _CT;
    return std::less<_CT>()(__x.get(), __y.get());
  }

template<typename _Tp, typename _Dp>
  inline bool
  operator<(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
  { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(),
						 nullptr); }

template<typename _Tp, typename _Dp>
  inline bool
  operator<(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
  { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr,
						 __x.get()); }

template<typename _Tp, typename _Dp,
  typename _Up, typename _Ep>
  inline bool
  operator<=(const unique_ptr<_Tp, _Dp>& __x,
      const unique_ptr<_Up, _Ep>& __y)
  { return !(__y < __x); }

template<typename _Tp, typename _Dp>
  inline bool
  operator<=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
  { return !(nullptr < __x); }

template<typename _Tp, typename _Dp>
  inline bool
  operator<=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
  { return !(__x < nullptr); }

template<typename _Tp, typename _Dp,
  typename _Up, typename _Ep>
  inline bool
  operator>(const unique_ptr<_Tp, _Dp>& __x,
     const unique_ptr<_Up, _Ep>& __y)
  { return (__y < __x); }

template<typename _Tp, typename _Dp>
  inline bool
  operator>(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
  { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(nullptr,
						 __x.get()); }

template<typename _Tp, typename _Dp>
  inline bool
  operator>(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
  { return std::less<typename unique_ptr<_Tp, _Dp>::pointer>()(__x.get(),
						 nullptr); }

template<typename _Tp, typename _Dp,
  typename _Up, typename _Ep>
  inline bool
  operator>=(const unique_ptr<_Tp, _Dp>& __x,
      const unique_ptr<_Up, _Ep>& __y)
  { return !(__x < __y); }

template<typename _Tp, typename _Dp>
  inline bool
  operator>=(const unique_ptr<_Tp, _Dp>& __x, nullptr_t)
  { return !(__x < nullptr); }

template<typename _Tp, typename _Dp>
  inline bool
  operator>=(nullptr_t, const unique_ptr<_Tp, _Dp>& __x)
  { return !(nullptr < __x); }

/// std::hash specialization for unique_ptr.
template<typename _Tp, typename _Dp>
  struct hash<unique_ptr<_Tp, _Dp>>
  : public __hash_base<size_t, unique_ptr<_Tp, _Dp>>,
  private __poison_hash<typename unique_ptr<_Tp, _Dp>::pointer>
  {
    size_t
    operator()(const unique_ptr<_Tp, _Dp>& __u) const noexcept
    {
typedef unique_ptr<_Tp, _Dp> _UP;
return std::hash<typename _UP::pointer>()(__u.get());
    }
  };

811#if __cplusplus201103L > 201103L

813#define __cpp_lib_make_unique 201304

template<typename _Tp>
  struct _MakeUniq
  { typedef unique_ptr<_Tp> __single_object; };

template<typename _Tp>
  struct _MakeUniq<_Tp[]>
  { typedef unique_ptr<_Tp[]> __array; };

template<typename _Tp, size_t _Bound>
  struct _MakeUniq<_Tp[_Bound]>
  { struct __invalid_type { }; };

/// std::make_unique for single objects
template<typename _Tp, typename... _Args>
  inline typename _MakeUniq<_Tp>::__single_object
  make_unique(_Args&&... __args)
  { return unique_ptr<_Tp>(new _Tp(std::forward<_Args>(__args)...)); }

/// std::make_unique for arrays of unknown bound
template<typename _Tp>
  inline typename _MakeUniq<_Tp>::__array
  make_unique(size_t __num)
  { return unique_ptr<_Tp>(new remove_extent_t<_Tp>[__num]()); }

/// Disable std::make_unique for arrays of known bound
template<typename _Tp, typename... _Args>
  inline typename _MakeUniq<_Tp>::__invalid_type
  make_unique(_Args&&...) = delete;
843#endif

// @} group pointer_abstractions

847_GLIBCXX_END_NAMESPACE_VERSION
848} // namespace

850#endif /* _UNIQUE_PTR_H */