/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp

Bug Summary

File:	tools/clang/lib/Sema/SemaTemplateDeduction.cpp
Warning:	line 3666, column 31 Called C++ object pointer is null

Annotated Source Code

Press '?' to see keyboard shortcuts

Show analyzer invocation

clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name SemaTemplateDeduction.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -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 -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mthread-model posix -mframe-pointer=none -relaxed-aliasing -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-10/lib/clang/10.0.0 -D CLANG_VENDOR="Debian " -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-10~svn374877/build-llvm/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema -I /build/llvm-toolchain-snapshot-10~svn374877/tools/clang/include -I /build/llvm-toolchain-snapshot-10~svn374877/build-llvm/tools/clang/include -I /build/llvm-toolchain-snapshot-10~svn374877/build-llvm/include -I /build/llvm-toolchain-snapshot-10~svn374877/include -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/x86_64-linux-gnu/c++/6.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/6.3.0/../../../../include/c++/6.3.0/backward -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-10/lib/clang/10.0.0/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-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-10~svn374877/build-llvm/tools/clang/lib/Sema -fdebug-prefix-map=/build/llvm-toolchain-snapshot-10~svn374877=. -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fobjc-runtime=gcc -fno-common -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -o /tmp/scan-build-2019-10-15-233810-7101-1 -x c++ /build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp

/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp

→

1//===- SemaTemplateDeduction.cpp - Template Argument Deduction ------------===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements C++ template argument deduction.
10//
11//===----------------------------------------------------------------------===//

13#include "clang/Sema/TemplateDeduction.h"
14#include "TreeTransform.h"
15#include "TypeLocBuilder.h"
16#include "clang/AST/ASTContext.h"
17#include "clang/AST/ASTLambda.h"
18#include "clang/AST/Decl.h"
19#include "clang/AST/DeclAccessPair.h"
20#include "clang/AST/DeclBase.h"
21#include "clang/AST/DeclCXX.h"
22#include "clang/AST/DeclTemplate.h"
23#include "clang/AST/DeclarationName.h"
24#include "clang/AST/Expr.h"
25#include "clang/AST/ExprCXX.h"
26#include "clang/AST/NestedNameSpecifier.h"
27#include "clang/AST/TemplateBase.h"
28#include "clang/AST/TemplateName.h"
29#include "clang/AST/Type.h"
30#include "clang/AST/TypeLoc.h"
31#include "clang/AST/UnresolvedSet.h"
32#include "clang/Basic/AddressSpaces.h"
33#include "clang/Basic/ExceptionSpecificationType.h"
34#include "clang/Basic/LLVM.h"
35#include "clang/Basic/LangOptions.h"
36#include "clang/Basic/PartialDiagnostic.h"
37#include "clang/Basic/SourceLocation.h"
38#include "clang/Basic/Specifiers.h"
39#include "clang/Sema/Ownership.h"
40#include "clang/Sema/Sema.h"
41#include "clang/Sema/Template.h"
42#include "llvm/ADT/APInt.h"
43#include "llvm/ADT/APSInt.h"
44#include "llvm/ADT/ArrayRef.h"
45#include "llvm/ADT/DenseMap.h"
46#include "llvm/ADT/FoldingSet.h"
47#include "llvm/ADT/Optional.h"
48#include "llvm/ADT/SmallBitVector.h"
49#include "llvm/ADT/SmallPtrSet.h"
50#include "llvm/ADT/SmallVector.h"
51#include "llvm/Support/Casting.h"
52#include "llvm/Support/Compiler.h"
53#include "llvm/Support/ErrorHandling.h"
54#include <algorithm>
55#include <cassert>
56#include <tuple>
57#include <utility>

59namespace clang {

/// Various flags that control template argument deduction.
///
/// These flags can be bitwise-OR'd together.
enum TemplateDeductionFlags {
  /// No template argument deduction flags, which indicates the
  /// strictest results for template argument deduction (as used for, e.g.,
  /// matching class template partial specializations).
  TDF_None = 0,

  /// Within template argument deduction from a function call, we are
  /// matching with a parameter type for which the original parameter was
  /// a reference.
  TDF_ParamWithReferenceType = 0x1,

  /// Within template argument deduction from a function call, we
  /// are matching in a case where we ignore cv-qualifiers.
  TDF_IgnoreQualifiers = 0x02,

  /// Within template argument deduction from a function call,
  /// we are matching in a case where we can perform template argument
  /// deduction from a template-id of a derived class of the argument type.
  TDF_DerivedClass = 0x04,

  /// Allow non-dependent types to differ, e.g., when performing
  /// template argument deduction from a function call where conversions
  /// may apply.
  TDF_SkipNonDependent = 0x08,

  /// Whether we are performing template argument deduction for
  /// parameters and arguments in a top-level template argument
  TDF_TopLevelParameterTypeList = 0x10,

  /// Within template argument deduction from overload resolution per
  /// C++ [over.over] allow matching function types that are compatible in
  /// terms of noreturn and default calling convention adjustments, or
  /// similarly matching a declared template specialization against a
  /// possible template, per C++ [temp.deduct.decl]. In either case, permit
  /// deduction where the parameter is a function type that can be converted
  /// to the argument type.
  TDF_AllowCompatibleFunctionType = 0x20,

  /// Within template argument deduction for a conversion function, we are
  /// matching with an argument type for which the original argument was
  /// a reference.
  TDF_ArgWithReferenceType = 0x40,
};
107}

109using namespace clang;
110using namespace sema;

112/// Compare two APSInts, extending and switching the sign as
113/// necessary to compare their values regardless of underlying type.
114static bool hasSameExtendedValue(llvm::APSInt X, llvm::APSInt Y) {
if (Y.getBitWidth() > X.getBitWidth())
  X = X.extend(Y.getBitWidth());
else if (Y.getBitWidth() < X.getBitWidth())
  Y = Y.extend(X.getBitWidth());

// If there is a signedness mismatch, correct it.
if (X.isSigned() != Y.isSigned()) {
  // If the signed value is negative, then the values cannot be the same.
  if ((Y.isSigned() && Y.isNegative()) || (X.isSigned() && X.isNegative()))
    return false;

  Y.setIsSigned(true);
  X.setIsSigned(true);
}

return X == Y;
131}

133static Sema::TemplateDeductionResult
134DeduceTemplateArguments(Sema &S,
                      TemplateParameterList *TemplateParams,
                      const TemplateArgument &Param,
                      TemplateArgument Arg,
                      TemplateDeductionInfo &Info,
                      SmallVectorImpl<DeducedTemplateArgument> &Deduced);

141static Sema::TemplateDeductionResult
142DeduceTemplateArgumentsByTypeMatch(Sema &S,
                                 TemplateParameterList *TemplateParams,
                                 QualType Param,
                                 QualType Arg,
                                 TemplateDeductionInfo &Info,
                                 SmallVectorImpl<DeducedTemplateArgument> &
                                                    Deduced,
                                 unsigned TDF,
                                 bool PartialOrdering = false,
                                 bool DeducedFromArrayBound = false);

153static Sema::TemplateDeductionResult
154DeduceTemplateArguments(Sema &S, TemplateParameterList *TemplateParams,
                      ArrayRef<TemplateArgument> Params,
                      ArrayRef<TemplateArgument> Args,
                      TemplateDeductionInfo &Info,
                      SmallVectorImpl<DeducedTemplateArgument> &Deduced,
                      bool NumberOfArgumentsMustMatch);

161static void MarkUsedTemplateParameters(ASTContext &Ctx,
                                     const TemplateArgument &TemplateArg,
                                     bool OnlyDeduced, unsigned Depth,
                                     llvm::SmallBitVector &Used);

166static void MarkUsedTemplateParameters(ASTContext &Ctx, QualType T,
                                     bool OnlyDeduced, unsigned Level,
                                     llvm::SmallBitVector &Deduced);

170/// If the given expression is of a form that permits the deduction
171/// of a non-type template parameter, return the declaration of that
172/// non-type template parameter.
173static NonTypeTemplateParmDecl *
174getDeducedParameterFromExpr(TemplateDeductionInfo &Info, Expr *E) {
// If we are within an alias template, the expression may have undergone
// any number of parameter substitutions already.
while (true) {
  if (ImplicitCastExpr *IC = dyn_cast<ImplicitCastExpr>(E))
    E = IC->getSubExpr();
  else if (ConstantExpr *CE = dyn_cast<ConstantExpr>(E))
    E = CE->getSubExpr();
  else if (SubstNonTypeTemplateParmExpr *Subst =
             dyn_cast<SubstNonTypeTemplateParmExpr>(E))
    E = Subst->getReplacement();
  else
    break;
}

if (DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E))
  if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl()))
    if (NTTP->getDepth() == Info.getDeducedDepth())
      return NTTP;

return nullptr;
195}

197/// Determine whether two declaration pointers refer to the same
198/// declaration.
199static bool isSameDeclaration(Decl *X, Decl *Y) {
if (NamedDecl *NX = dyn_cast<NamedDecl>(X))
  X = NX->getUnderlyingDecl();
if (NamedDecl *NY = dyn_cast<NamedDecl>(Y))
  Y = NY->getUnderlyingDecl();

return X->getCanonicalDecl() == Y->getCanonicalDecl();
206}

208/// Verify that the given, deduced template arguments are compatible.
209///
210/// \returns The deduced template argument, or a NULL template argument if
211/// the deduced template arguments were incompatible.
212static DeducedTemplateArgument
213checkDeducedTemplateArguments(ASTContext &Context,
                            const DeducedTemplateArgument &X,
                            const DeducedTemplateArgument &Y) {
// We have no deduction for one or both of the arguments; they're compatible.
if (X.isNull())
  return Y;
if (Y.isNull())
  return X;

// If we have two non-type template argument values deduced for the same
// parameter, they must both match the type of the parameter, and thus must
// match each other's type. As we're only keeping one of them, we must check
// for that now. The exception is that if either was deduced from an array
// bound, the type is permitted to differ.
if (!X.wasDeducedFromArrayBound() && !Y.wasDeducedFromArrayBound()) {
  QualType XType = X.getNonTypeTemplateArgumentType();
  if (!XType.isNull()) {
    QualType YType = Y.getNonTypeTemplateArgumentType();
    if (YType.isNull() || !Context.hasSameType(XType, YType))
      return DeducedTemplateArgument();
  }
}

switch (X.getKind()) {
case TemplateArgument::Null:
  llvm_unreachable("Non-deduced template arguments handled above")::llvm::llvm_unreachable_internal("Non-deduced template arguments handled above"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 238);

case TemplateArgument::Type:
  // If two template type arguments have the same type, they're compatible.
  if (Y.getKind() == TemplateArgument::Type &&
      Context.hasSameType(X.getAsType(), Y.getAsType()))
    return X;

  // If one of the two arguments was deduced from an array bound, the other
  // supersedes it.
  if (X.wasDeducedFromArrayBound() != Y.wasDeducedFromArrayBound())
    return X.wasDeducedFromArrayBound() ? Y : X;

  // The arguments are not compatible.
  return DeducedTemplateArgument();

case TemplateArgument::Integral:
  // If we deduced a constant in one case and either a dependent expression or
  // declaration in another case, keep the integral constant.
  // If both are integral constants with the same value, keep that value.
  if (Y.getKind() == TemplateArgument::Expression ||
      Y.getKind() == TemplateArgument::Declaration ||
      (Y.getKind() == TemplateArgument::Integral &&
       hasSameExtendedValue(X.getAsIntegral(), Y.getAsIntegral())))
    return X.wasDeducedFromArrayBound() ? Y : X;

  // All other combinations are incompatible.
  return DeducedTemplateArgument();

case TemplateArgument::Template:
  if (Y.getKind() == TemplateArgument::Template &&
      Context.hasSameTemplateName(X.getAsTemplate(), Y.getAsTemplate()))
    return X;

  // All other combinations are incompatible.
  return DeducedTemplateArgument();

case TemplateArgument::TemplateExpansion:
  if (Y.getKind() == TemplateArgument::TemplateExpansion &&
      Context.hasSameTemplateName(X.getAsTemplateOrTemplatePattern(),
                                  Y.getAsTemplateOrTemplatePattern()))
    return X;

  // All other combinations are incompatible.
  return DeducedTemplateArgument();

case TemplateArgument::Expression: {
  if (Y.getKind() != TemplateArgument::Expression)
    return checkDeducedTemplateArguments(Context, Y, X);

  // Compare the expressions for equality
  llvm::FoldingSetNodeID ID1, ID2;
  X.getAsExpr()->Profile(ID1, Context, true);
  Y.getAsExpr()->Profile(ID2, Context, true);
  if (ID1 == ID2)
    return X.wasDeducedFromArrayBound() ? Y : X;

  // Differing dependent expressions are incompatible.
  return DeducedTemplateArgument();
}

case TemplateArgument::Declaration:
  assert(!X.wasDeducedFromArrayBound())((!X.wasDeducedFromArrayBound()) ? static_cast<void> (0
) : __assert_fail ("!X.wasDeducedFromArrayBound()", "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 300, __PRETTY_FUNCTION__));

  // If we deduced a declaration and a dependent expression, keep the
  // declaration.
  if (Y.getKind() == TemplateArgument::Expression)
    return X;

  // If we deduced a declaration and an integral constant, keep the
  // integral constant and whichever type did not come from an array
  // bound.
  if (Y.getKind() == TemplateArgument::Integral) {
    if (Y.wasDeducedFromArrayBound())
      return TemplateArgument(Context, Y.getAsIntegral(),
                              X.getParamTypeForDecl());
    return Y;
  }

  // If we deduced two declarations, make sure that they refer to the
  // same declaration.
  if (Y.getKind() == TemplateArgument::Declaration &&
      isSameDeclaration(X.getAsDecl(), Y.getAsDecl()))
    return X;

  // All other combinations are incompatible.
  return DeducedTemplateArgument();

case TemplateArgument::NullPtr:
  // If we deduced a null pointer and a dependent expression, keep the
  // null pointer.
  if (Y.getKind() == TemplateArgument::Expression)
    return X;

  // If we deduced a null pointer and an integral constant, keep the
  // integral constant.
  if (Y.getKind() == TemplateArgument::Integral)
    return Y;

  // If we deduced two null pointers, they are the same.
  if (Y.getKind() == TemplateArgument::NullPtr)
    return X;

  // All other combinations are incompatible.
  return DeducedTemplateArgument();

case TemplateArgument::Pack: {
  if (Y.getKind() != TemplateArgument::Pack ||
      X.pack_size() != Y.pack_size())
    return DeducedTemplateArgument();

  llvm::SmallVector<TemplateArgument, 8> NewPack;
  for (TemplateArgument::pack_iterator XA = X.pack_begin(),
                                    XAEnd = X.pack_end(),
                                       YA = Y.pack_begin();
       XA != XAEnd; ++XA, ++YA) {
    TemplateArgument Merged = checkDeducedTemplateArguments(
        Context, DeducedTemplateArgument(*XA, X.wasDeducedFromArrayBound()),
        DeducedTemplateArgument(*YA, Y.wasDeducedFromArrayBound()));
    if (Merged.isNull())
      return DeducedTemplateArgument();
    NewPack.push_back(Merged);
  }

  return DeducedTemplateArgument(
      TemplateArgument::CreatePackCopy(Context, NewPack),
      X.wasDeducedFromArrayBound() && Y.wasDeducedFromArrayBound());
}
}

llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 368);
369}

371/// Deduce the value of the given non-type template parameter
372/// as the given deduced template argument. All non-type template parameter
373/// deduction is funneled through here.
374static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument(
  Sema &S, TemplateParameterList *TemplateParams,
  NonTypeTemplateParmDecl *NTTP, const DeducedTemplateArgument &NewDeduced,
  QualType ValueType, TemplateDeductionInfo &Info,
  SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
assert(NTTP->getDepth() == Info.getDeducedDepth() &&((NTTP->getDepth() == Info.getDeducedDepth() && "deducing non-type template argument with wrong depth"
) ? static_cast<void> (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"deducing non-type template argument with wrong depth\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 380, __PRETTY_FUNCTION__))
       "deducing non-type template argument with wrong depth")((NTTP->getDepth() == Info.getDeducedDepth() && "deducing non-type template argument with wrong depth"
) ? static_cast<void> (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"deducing non-type template argument with wrong depth\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 380, __PRETTY_FUNCTION__));

DeducedTemplateArgument Result = checkDeducedTemplateArguments(
    S.Context, Deduced[NTTP->getIndex()], NewDeduced);
if (Result.isNull()) {
  Info.Param = NTTP;
  Info.FirstArg = Deduced[NTTP->getIndex()];
  Info.SecondArg = NewDeduced;
  return Sema::TDK_Inconsistent;
}

Deduced[NTTP->getIndex()] = Result;
if (!S.getLangOpts().CPlusPlus17)
  return Sema::TDK_Success;

if (NTTP->isExpandedParameterPack())
  // FIXME: We may still need to deduce parts of the type here! But we
  // don't have any way to find which slice of the type to use, and the
  // type stored on the NTTP itself is nonsense. Perhaps the type of an
  // expanded NTTP should be a pack expansion type?
  return Sema::TDK_Success;

// Get the type of the parameter for deduction. If it's a (dependent) array
// or function type, we will not have decayed it yet, so do that now.
QualType ParamType = S.Context.getAdjustedParameterType(NTTP->getType());
if (auto *Expansion = dyn_cast<PackExpansionType>(ParamType))
  ParamType = Expansion->getPattern();

// FIXME: It's not clear how deduction of a parameter of reference
// type from an argument (of non-reference type) should be performed.
// For now, we just remove reference types from both sides and let
// the final check for matching types sort out the mess.
return DeduceTemplateArgumentsByTypeMatch(
    S, TemplateParams, ParamType.getNonReferenceType(),
    ValueType.getNonReferenceType(), Info, Deduced, TDF_SkipNonDependent,
    /*PartialOrdering=*/false,
    /*ArrayBound=*/NewDeduced.wasDeducedFromArrayBound());
417}

419/// Deduce the value of the given non-type template parameter
420/// from the given integral constant.
421static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument(
  Sema &S, TemplateParameterList *TemplateParams,
  NonTypeTemplateParmDecl *NTTP, const llvm::APSInt &Value,
  QualType ValueType, bool DeducedFromArrayBound, TemplateDeductionInfo &Info,
  SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
return DeduceNonTypeTemplateArgument(
    S, TemplateParams, NTTP,
    DeducedTemplateArgument(S.Context, Value, ValueType,
                            DeducedFromArrayBound),
    ValueType, Info, Deduced);
431}

433/// Deduce the value of the given non-type template parameter
434/// from the given null pointer template argument type.
435static Sema::TemplateDeductionResult DeduceNullPtrTemplateArgument(
  Sema &S, TemplateParameterList *TemplateParams,
  NonTypeTemplateParmDecl *NTTP, QualType NullPtrType,
  TemplateDeductionInfo &Info,
  SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
Expr *Value =
    S.ImpCastExprToType(new (S.Context) CXXNullPtrLiteralExpr(
                            S.Context.NullPtrTy, NTTP->getLocation()),
                        NullPtrType, CK_NullToPointer)
        .get();
return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
                                     DeducedTemplateArgument(Value),
                                     Value->getType(), Info, Deduced);
448}

450/// Deduce the value of the given non-type template parameter
451/// from the given type- or value-dependent expression.
452///
453/// \returns true if deduction succeeded, false otherwise.
454static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument(
  Sema &S, TemplateParameterList *TemplateParams,
  NonTypeTemplateParmDecl *NTTP, Expr *Value, TemplateDeductionInfo &Info,
  SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
                                     DeducedTemplateArgument(Value),
                                     Value->getType(), Info, Deduced);
461}

463/// Deduce the value of the given non-type template parameter
464/// from the given declaration.
465///
466/// \returns true if deduction succeeded, false otherwise.
467static Sema::TemplateDeductionResult DeduceNonTypeTemplateArgument(
  Sema &S, TemplateParameterList *TemplateParams,
  NonTypeTemplateParmDecl *NTTP, ValueDecl *D, QualType T,
  TemplateDeductionInfo &Info,
  SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
D = D ? cast<ValueDecl>(D->getCanonicalDecl()) : nullptr;
TemplateArgument New(D, T);
return DeduceNonTypeTemplateArgument(
    S, TemplateParams, NTTP, DeducedTemplateArgument(New), T, Info, Deduced);
476}

478static Sema::TemplateDeductionResult
479DeduceTemplateArguments(Sema &S,
                      TemplateParameterList *TemplateParams,
                      TemplateName Param,
                      TemplateName Arg,
                      TemplateDeductionInfo &Info,
                      SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
TemplateDecl *ParamDecl = Param.getAsTemplateDecl();
if (!ParamDecl) {
  // The parameter type is dependent and is not a template template parameter,
  // so there is nothing that we can deduce.
  return Sema::TDK_Success;
}

if (TemplateTemplateParmDecl *TempParam
      = dyn_cast<TemplateTemplateParmDecl>(ParamDecl)) {
  // If we're not deducing at this depth, there's nothing to deduce.
  if (TempParam->getDepth() != Info.getDeducedDepth())
    return Sema::TDK_Success;

  DeducedTemplateArgument NewDeduced(S.Context.getCanonicalTemplateName(Arg));
  DeducedTemplateArgument Result = checkDeducedTemplateArguments(S.Context,
                                               Deduced[TempParam->getIndex()],
                                                                 NewDeduced);
  if (Result.isNull()) {
    Info.Param = TempParam;
    Info.FirstArg = Deduced[TempParam->getIndex()];
    Info.SecondArg = NewDeduced;
    return Sema::TDK_Inconsistent;
  }

  Deduced[TempParam->getIndex()] = Result;
  return Sema::TDK_Success;
}

// Verify that the two template names are equivalent.
if (S.Context.hasSameTemplateName(Param, Arg))
  return Sema::TDK_Success;

// Mismatch of non-dependent template parameter to argument.
Info.FirstArg = TemplateArgument(Param);
Info.SecondArg = TemplateArgument(Arg);
return Sema::TDK_NonDeducedMismatch;
521}

523/// Deduce the template arguments by comparing the template parameter
524/// type (which is a template-id) with the template argument type.
525///
526/// \param S the Sema
527///
528/// \param TemplateParams the template parameters that we are deducing
529///
530/// \param Param the parameter type
531///
532/// \param Arg the argument type
533///
534/// \param Info information about the template argument deduction itself
535///
536/// \param Deduced the deduced template arguments
537///
538/// \returns the result of template argument deduction so far. Note that a
539/// "success" result means that template argument deduction has not yet failed,
540/// but it may still fail, later, for other reasons.
541static Sema::TemplateDeductionResult
542DeduceTemplateArguments(Sema &S,
                      TemplateParameterList *TemplateParams,
                      const TemplateSpecializationType *Param,
                      QualType Arg,
                      TemplateDeductionInfo &Info,
                      SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
assert(Arg.isCanonical() && "Argument type must be canonical")((Arg.isCanonical() && "Argument type must be canonical"
) ? static_cast<void> (0) : __assert_fail ("Arg.isCanonical() && \"Argument type must be canonical\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 548, __PRETTY_FUNCTION__));

// Treat an injected-class-name as its underlying template-id.
if (auto *Injected = dyn_cast<InjectedClassNameType>(Arg))
  Arg = Injected->getInjectedSpecializationType();

// Check whether the template argument is a dependent template-id.
if (const TemplateSpecializationType *SpecArg
      = dyn_cast<TemplateSpecializationType>(Arg)) {
  // Perform template argument deduction for the template name.
  if (Sema::TemplateDeductionResult Result
        = DeduceTemplateArguments(S, TemplateParams,
                                  Param->getTemplateName(),
                                  SpecArg->getTemplateName(),
                                  Info, Deduced))
    return Result;


  // Perform template argument deduction on each template
  // argument. Ignore any missing/extra arguments, since they could be
  // filled in by default arguments.
  return DeduceTemplateArguments(S, TemplateParams,
                                 Param->template_arguments(),
                                 SpecArg->template_arguments(), Info, Deduced,
                                 /*NumberOfArgumentsMustMatch=*/false);
}

// If the argument type is a class template specialization, we
// perform template argument deduction using its template
// arguments.
const RecordType *RecordArg = dyn_cast<RecordType>(Arg);
if (!RecordArg) {
  Info.FirstArg = TemplateArgument(QualType(Param, 0));
  Info.SecondArg = TemplateArgument(Arg);
  return Sema::TDK_NonDeducedMismatch;
}

ClassTemplateSpecializationDecl *SpecArg
  = dyn_cast<ClassTemplateSpecializationDecl>(RecordArg->getDecl());
if (!SpecArg) {
  Info.FirstArg = TemplateArgument(QualType(Param, 0));
  Info.SecondArg = TemplateArgument(Arg);
  return Sema::TDK_NonDeducedMismatch;
}

// Perform template argument deduction for the template name.
if (Sema::TemplateDeductionResult Result
      = DeduceTemplateArguments(S,
                                TemplateParams,
                                Param->getTemplateName(),
                             TemplateName(SpecArg->getSpecializedTemplate()),
                                Info, Deduced))
  return Result;

// Perform template argument deduction for the template arguments.
return DeduceTemplateArguments(S, TemplateParams, Param->template_arguments(),
                               SpecArg->getTemplateArgs().asArray(), Info,
                               Deduced, /*NumberOfArgumentsMustMatch=*/true);
606}

608/// Determines whether the given type is an opaque type that
609/// might be more qualified when instantiated.
610static bool IsPossiblyOpaquelyQualifiedType(QualType T) {
switch (T->getTypeClass()) {
case Type::TypeOfExpr:
case Type::TypeOf:
case Type::DependentName:
case Type::Decltype:
case Type::UnresolvedUsing:
case Type::TemplateTypeParm:
  return true;

case Type::ConstantArray:
case Type::IncompleteArray:
case Type::VariableArray:
case Type::DependentSizedArray:
  return IsPossiblyOpaquelyQualifiedType(
                                    cast<ArrayType>(T)->getElementType());

default:
  return false;
}
630}

632/// Helper function to build a TemplateParameter when we don't
633/// know its type statically.
634static TemplateParameter makeTemplateParameter(Decl *D) {
if (TemplateTypeParmDecl *TTP = dyn_cast<TemplateTypeParmDecl>(D))
  return TemplateParameter(TTP);
if (NonTypeTemplateParmDecl *NTTP = dyn_cast<NonTypeTemplateParmDecl>(D))
  return TemplateParameter(NTTP);

return TemplateParameter(cast<TemplateTemplateParmDecl>(D));
641}

643/// If \p Param is an expanded parameter pack, get the number of expansions.
644static Optional<unsigned> getExpandedPackSize(NamedDecl *Param) {
if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(Param))
  if (NTTP->isExpandedParameterPack())
    return NTTP->getNumExpansionTypes();

if (auto *TTP = dyn_cast<TemplateTemplateParmDecl>(Param))
  if (TTP->isExpandedParameterPack())
    return TTP->getNumExpansionTemplateParameters();

return None;
654}

656/// A pack that we're currently deducing.
657struct clang::DeducedPack {
// The index of the pack.
unsigned Index;

// The old value of the pack before we started deducing it.
DeducedTemplateArgument Saved;

// A deferred value of this pack from an inner deduction, that couldn't be
// deduced because this deduction hadn't happened yet.
DeducedTemplateArgument DeferredDeduction;

// The new value of the pack.
SmallVector<DeducedTemplateArgument, 4> New;

// The outer deduction for this pack, if any.
DeducedPack *Outer = nullptr;

DeducedPack(unsigned Index) : Index(Index) {}
675};

677namespace {

679/// A scope in which we're performing pack deduction.
680class PackDeductionScope {
681public:
/// Prepare to deduce the packs named within Pattern.
PackDeductionScope(Sema &S, TemplateParameterList *TemplateParams,
                   SmallVectorImpl<DeducedTemplateArgument> &Deduced,
                   TemplateDeductionInfo &Info, TemplateArgument Pattern)
    : S(S), TemplateParams(TemplateParams), Deduced(Deduced), Info(Info) {
  unsigned NumNamedPacks = addPacks(Pattern);
  finishConstruction(NumNamedPacks);
}

/// Prepare to directly deduce arguments of the parameter with index \p Index.
PackDeductionScope(Sema &S, TemplateParameterList *TemplateParams,
                   SmallVectorImpl<DeducedTemplateArgument> &Deduced,
                   TemplateDeductionInfo &Info, unsigned Index)
    : S(S), TemplateParams(TemplateParams), Deduced(Deduced), Info(Info) {
  addPack(Index);
  finishConstruction(1);
}

700private:
void addPack(unsigned Index) {
  // Save the deduced template argument for the parameter pack expanded
  // by this pack expansion, then clear out the deduction.
  DeducedPack Pack(Index);
  Pack.Saved = Deduced[Index];
  Deduced[Index] = TemplateArgument();

  // FIXME: What if we encounter multiple packs with different numbers of
  // pre-expanded expansions? (This should already have been diagnosed
  // during substitution.)
  if (Optional<unsigned> ExpandedPackExpansions =
          getExpandedPackSize(TemplateParams->getParam(Index)))
    FixedNumExpansions = ExpandedPackExpansions;

  Packs.push_back(Pack);
}

unsigned addPacks(TemplateArgument Pattern) {
  // Compute the set of template parameter indices that correspond to
  // parameter packs expanded by the pack expansion.
  llvm::SmallBitVector SawIndices(TemplateParams->size());

  auto AddPack = [&](unsigned Index) {
    if (SawIndices[Index])
      return;
    SawIndices[Index] = true;
    addPack(Index);
  };

  // First look for unexpanded packs in the pattern.
  SmallVector<UnexpandedParameterPack, 2> Unexpanded;
  S.collectUnexpandedParameterPacks(Pattern, Unexpanded);
  for (unsigned I = 0, N = Unexpanded.size(); I != N; ++I) {
    unsigned Depth, Index;
    std::tie(Depth, Index) = getDepthAndIndex(Unexpanded[I]);
    if (Depth == Info.getDeducedDepth())
      AddPack(Index);
  }
  assert(!Packs.empty() && "Pack expansion without unexpanded packs?")((!Packs.empty() && "Pack expansion without unexpanded packs?"
) ? static_cast<void> (0) : __assert_fail ("!Packs.empty() && \"Pack expansion without unexpanded packs?\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 739, __PRETTY_FUNCTION__));

  unsigned NumNamedPacks = Packs.size();

  // We can also have deduced template parameters that do not actually
  // appear in the pattern, but can be deduced by it (the type of a non-type
  // template parameter pack, in particular). These won't have prevented us
  // from partially expanding the pack.
  llvm::SmallBitVector Used(TemplateParams->size());
  MarkUsedTemplateParameters(S.Context, Pattern, /*OnlyDeduced*/true,
                             Info.getDeducedDepth(), Used);
  for (int Index = Used.find_first(); Index != -1;
       Index = Used.find_next(Index))
    if (TemplateParams->getParam(Index)->isParameterPack())
      AddPack(Index);

  return NumNamedPacks;
}

void finishConstruction(unsigned NumNamedPacks) {
  // Dig out the partially-substituted pack, if there is one.
  const TemplateArgument *PartialPackArgs = nullptr;
  unsigned NumPartialPackArgs = 0;
  std::pair<unsigned, unsigned> PartialPackDepthIndex(-1u, -1u);
  if (auto *Scope = S.CurrentInstantiationScope)
    if (auto *Partial = Scope->getPartiallySubstitutedPack(
            &PartialPackArgs, &NumPartialPackArgs))
      PartialPackDepthIndex = getDepthAndIndex(Partial);

  // This pack expansion will have been partially or fully expanded if
  // it only names explicitly-specified parameter packs (including the
  // partially-substituted one, if any).
  bool IsExpanded = true;
  for (unsigned I = 0; I != NumNamedPacks; ++I) {
    if (Packs[I].Index >= Info.getNumExplicitArgs()) {
      IsExpanded = false;
      IsPartiallyExpanded = false;
      break;
    }
    if (PartialPackDepthIndex ==
          std::make_pair(Info.getDeducedDepth(), Packs[I].Index)) {
      IsPartiallyExpanded = true;
    }
  }

  // Skip over the pack elements that were expanded into separate arguments.
  // If we partially expanded, this is the number of partial arguments.
  if (IsPartiallyExpanded)
    PackElements += NumPartialPackArgs;
  else if (IsExpanded)
    PackElements += *FixedNumExpansions;

  for (auto &Pack : Packs) {
    if (Info.PendingDeducedPacks.size() > Pack.Index)
      Pack.Outer = Info.PendingDeducedPacks[Pack.Index];
    else
      Info.PendingDeducedPacks.resize(Pack.Index + 1);
    Info.PendingDeducedPacks[Pack.Index] = &Pack;

    if (PartialPackDepthIndex ==
          std::make_pair(Info.getDeducedDepth(), Pack.Index)) {
      Pack.New.append(PartialPackArgs, PartialPackArgs + NumPartialPackArgs);
      // We pre-populate the deduced value of the partially-substituted
      // pack with the specified value. This is not entirely correct: the
      // value is supposed to have been substituted, not deduced, but the
      // cases where this is observable require an exact type match anyway.
      //
      // FIXME: If we could represent a "depth i, index j, pack elem k"
      // parameter, we could substitute the partially-substituted pack
      // everywhere and avoid this.
      if (!IsPartiallyExpanded)
        Deduced[Pack.Index] = Pack.New[PackElements];
    }
  }
}

815public:
~PackDeductionScope() {
  for (auto &Pack : Packs)
    Info.PendingDeducedPacks[Pack.Index] = Pack.Outer;
}

/// Determine whether this pack has already been partially expanded into a
/// sequence of (prior) function parameters / template arguments.
bool isPartiallyExpanded() { return IsPartiallyExpanded; }

/// Determine whether this pack expansion scope has a known, fixed arity.
/// This happens if it involves a pack from an outer template that has
/// (notionally) already been expanded.
bool hasFixedArity() { return FixedNumExpansions.hasValue(); }

/// Determine whether the next element of the argument is still part of this
/// pack. This is the case unless the pack is already expanded to a fixed
/// length.
bool hasNextElement() {
  return !FixedNumExpansions || *FixedNumExpansions > PackElements;
}

/// Move to deducing the next element in each pack that is being deduced.
void nextPackElement() {
  // Capture the deduced template arguments for each parameter pack expanded
  // by this pack expansion, add them to the list of arguments we've deduced
  // for that pack, then clear out the deduced argument.
  for (auto &Pack : Packs) {
    DeducedTemplateArgument &DeducedArg = Deduced[Pack.Index];
    if (!Pack.New.empty() || !DeducedArg.isNull()) {
      while (Pack.New.size() < PackElements)
        Pack.New.push_back(DeducedTemplateArgument());
      if (Pack.New.size() == PackElements)
        Pack.New.push_back(DeducedArg);
      else
        Pack.New[PackElements] = DeducedArg;
      DeducedArg = Pack.New.size() > PackElements + 1
                       ? Pack.New[PackElements + 1]
                       : DeducedTemplateArgument();
    }
  }
  ++PackElements;
}

/// Finish template argument deduction for a set of argument packs,
/// producing the argument packs and checking for consistency with prior
/// deductions.
Sema::TemplateDeductionResult
finish(bool TreatNoDeductionsAsNonDeduced = true) {
  // Build argument packs for each of the parameter packs expanded by this
  // pack expansion.
  for (auto &Pack : Packs) {
    // Put back the old value for this pack.
    Deduced[Pack.Index] = Pack.Saved;

    // If we are deducing the size of this pack even if we didn't deduce any
    // values for it, then make sure we build a pack of the right size.
    // FIXME: Should we always deduce the size, even if the pack appears in
    // a non-deduced context?
    if (!TreatNoDeductionsAsNonDeduced)
      Pack.New.resize(PackElements);

    // Build or find a new value for this pack.
    DeducedTemplateArgument NewPack;
    if (PackElements && Pack.New.empty()) {
      if (Pack.DeferredDeduction.isNull()) {
        // We were not able to deduce anything for this parameter pack
        // (because it only appeared in non-deduced contexts), so just
        // restore the saved argument pack.
        continue;
      }

      NewPack = Pack.DeferredDeduction;
      Pack.DeferredDeduction = TemplateArgument();
    } else if (Pack.New.empty()) {
      // If we deduced an empty argument pack, create it now.
      NewPack = DeducedTemplateArgument(TemplateArgument::getEmptyPack());
    } else {
      TemplateArgument *ArgumentPack =
          new (S.Context) TemplateArgument[Pack.New.size()];
      std::copy(Pack.New.begin(), Pack.New.end(), ArgumentPack);
      NewPack = DeducedTemplateArgument(
          TemplateArgument(llvm::makeArrayRef(ArgumentPack, Pack.New.size())),
          // FIXME: This is wrong, it's possible that some pack elements are
          // deduced from an array bound and others are not:
          //   template<typename ...T, T ...V> void g(const T (&...p)[V]);
          //   g({1, 2, 3}, {{}, {}});
          // ... should deduce T = {int, size_t (from array bound)}.
          Pack.New[0].wasDeducedFromArrayBound());
    }

    // Pick where we're going to put the merged pack.
    DeducedTemplateArgument *Loc;
    if (Pack.Outer) {
      if (Pack.Outer->DeferredDeduction.isNull()) {
        // Defer checking this pack until we have a complete pack to compare
        // it against.
        Pack.Outer->DeferredDeduction = NewPack;
        continue;
      }
      Loc = &Pack.Outer->DeferredDeduction;
    } else {
      Loc = &Deduced[Pack.Index];
    }

    // Check the new pack matches any previous value.
    DeducedTemplateArgument OldPack = *Loc;
    DeducedTemplateArgument Result =
        checkDeducedTemplateArguments(S.Context, OldPack, NewPack);

    // If we deferred a deduction of this pack, check that one now too.
    if (!Result.isNull() && !Pack.DeferredDeduction.isNull()) {
      OldPack = Result;
      NewPack = Pack.DeferredDeduction;
      Result = checkDeducedTemplateArguments(S.Context, OldPack, NewPack);
    }

    NamedDecl *Param = TemplateParams->getParam(Pack.Index);
    if (Result.isNull()) {
      Info.Param = makeTemplateParameter(Param);
      Info.FirstArg = OldPack;
      Info.SecondArg = NewPack;
      return Sema::TDK_Inconsistent;
    }

    // If we have a pre-expanded pack and we didn't deduce enough elements
    // for it, fail deduction.
    if (Optional<unsigned> Expansions = getExpandedPackSize(Param)) {
      if (*Expansions != PackElements) {
        Info.Param = makeTemplateParameter(Param);
        Info.FirstArg = Result;
        return Sema::TDK_IncompletePack;
      }
    }

    *Loc = Result;
  }

  return Sema::TDK_Success;
}

956private:
Sema &S;
TemplateParameterList *TemplateParams;
SmallVectorImpl<DeducedTemplateArgument> &Deduced;
TemplateDeductionInfo &Info;
unsigned PackElements = 0;
bool IsPartiallyExpanded = false;
/// The number of expansions, if we have a fully-expanded pack in this scope.
Optional<unsigned> FixedNumExpansions;

SmallVector<DeducedPack, 2> Packs;
967};

969} // namespace

971/// Deduce the template arguments by comparing the list of parameter
972/// types to the list of argument types, as in the parameter-type-lists of
973/// function types (C++ [temp.deduct.type]p10).
974///
975/// \param S The semantic analysis object within which we are deducing
976///
977/// \param TemplateParams The template parameters that we are deducing
978///
979/// \param Params The list of parameter types
980///
981/// \param NumParams The number of types in \c Params
982///
983/// \param Args The list of argument types
984///
985/// \param NumArgs The number of types in \c Args
986///
987/// \param Info information about the template argument deduction itself
988///
989/// \param Deduced the deduced template arguments
990///
991/// \param TDF bitwise OR of the TemplateDeductionFlags bits that describe
992/// how template argument deduction is performed.
993///
994/// \param PartialOrdering If true, we are performing template argument
995/// deduction for during partial ordering for a call
996/// (C++0x [temp.deduct.partial]).
997///
998/// \returns the result of template argument deduction so far. Note that a
999/// "success" result means that template argument deduction has not yet failed,
1000/// but it may still fail, later, for other reasons.
1001static Sema::TemplateDeductionResult
1002DeduceTemplateArguments(Sema &S,
                      TemplateParameterList *TemplateParams,
                      const QualType *Params, unsigned NumParams,
                      const QualType *Args, unsigned NumArgs,
                      TemplateDeductionInfo &Info,
                      SmallVectorImpl<DeducedTemplateArgument> &Deduced,
                      unsigned TDF,
                      bool PartialOrdering = false) {
// C++0x [temp.deduct.type]p10:
//   Similarly, if P has a form that contains (T), then each parameter type
//   Pi of the respective parameter-type- list of P is compared with the
//   corresponding parameter type Ai of the corresponding parameter-type-list
//   of A. [...]
unsigned ArgIdx = 0, ParamIdx = 0;
for (; ParamIdx != NumParams; ++ParamIdx) {
  // Check argument types.
  const PackExpansionType *Expansion
                              = dyn_cast<PackExpansionType>(Params[ParamIdx]);
  if (!Expansion) {
    // Simple case: compare the parameter and argument types at this point.

    // Make sure we have an argument.
    if (ArgIdx >= NumArgs)
      return Sema::TDK_MiscellaneousDeductionFailure;

    if (isa<PackExpansionType>(Args[ArgIdx])) {
      // C++0x [temp.deduct.type]p22:
      //   If the original function parameter associated with A is a function
      //   parameter pack and the function parameter associated with P is not
      //   a function parameter pack, then template argument deduction fails.
      return Sema::TDK_MiscellaneousDeductionFailure;
    }

    if (Sema::TemplateDeductionResult Result
          = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                               Params[ParamIdx], Args[ArgIdx],
                                               Info, Deduced, TDF,
                                               PartialOrdering))
      return Result;

    ++ArgIdx;
    continue;
  }

  // C++0x [temp.deduct.type]p10:
  //   If the parameter-declaration corresponding to Pi is a function
  //   parameter pack, then the type of its declarator- id is compared with
  //   each remaining parameter type in the parameter-type-list of A. Each
  //   comparison deduces template arguments for subsequent positions in the
  //   template parameter packs expanded by the function parameter pack.

  QualType Pattern = Expansion->getPattern();
  PackDeductionScope PackScope(S, TemplateParams, Deduced, Info, Pattern);

  // A pack scope with fixed arity is not really a pack any more, so is not
  // a non-deduced context.
  if (ParamIdx + 1 == NumParams || PackScope.hasFixedArity()) {
    for (; ArgIdx < NumArgs && PackScope.hasNextElement(); ++ArgIdx) {
      // Deduce template arguments from the pattern.
      if (Sema::TemplateDeductionResult Result
            = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, Pattern,
                                                 Args[ArgIdx], Info, Deduced,
                                                 TDF, PartialOrdering))
        return Result;

      PackScope.nextPackElement();
    }
  } else {
    // C++0x [temp.deduct.type]p5:
    //   The non-deduced contexts are:
    //     - A function parameter pack that does not occur at the end of the
    //       parameter-declaration-clause.
    //
    // FIXME: There is no wording to say what we should do in this case. We
    // choose to resolve this by applying the same rule that is applied for a
    // function call: that is, deduce all contained packs to their
    // explicitly-specified values (or to <> if there is no such value).
    //
    // This is seemingly-arbitrarily different from the case of a template-id
    // with a non-trailing pack-expansion in its arguments, which renders the
    // entire template-argument-list a non-deduced context.

    // If the parameter type contains an explicitly-specified pack that we
    // could not expand, skip the number of parameters notionally created
    // by the expansion.
    Optional<unsigned> NumExpansions = Expansion->getNumExpansions();
    if (NumExpansions && !PackScope.isPartiallyExpanded()) {
      for (unsigned I = 0; I != *NumExpansions && ArgIdx < NumArgs;
           ++I, ++ArgIdx)
        PackScope.nextPackElement();
    }
  }

  // Build argument packs for each of the parameter packs expanded by this
  // pack expansion.
  if (auto Result = PackScope.finish())
    return Result;
}

// Make sure we don't have any extra arguments.
if (ArgIdx < NumArgs)
  return Sema::TDK_MiscellaneousDeductionFailure;

return Sema::TDK_Success;
1106}

1108/// Determine whether the parameter has qualifiers that the argument
1109/// lacks. Put another way, determine whether there is no way to add
1110/// a deduced set of qualifiers to the ParamType that would result in
1111/// its qualifiers matching those of the ArgType.
1112static bool hasInconsistentOrSupersetQualifiersOf(QualType ParamType,
                                                QualType ArgType) {
Qualifiers ParamQs = ParamType.getQualifiers();
Qualifiers ArgQs = ArgType.getQualifiers();

if (ParamQs == ArgQs)
  return false;

// Mismatched (but not missing) Objective-C GC attributes.
if (ParamQs.getObjCGCAttr() != ArgQs.getObjCGCAttr() &&
    ParamQs.hasObjCGCAttr())
  return true;

// Mismatched (but not missing) address spaces.
if (ParamQs.getAddressSpace() != ArgQs.getAddressSpace() &&
    ParamQs.hasAddressSpace())
  return true;

// Mismatched (but not missing) Objective-C lifetime qualifiers.
if (ParamQs.getObjCLifetime() != ArgQs.getObjCLifetime() &&
    ParamQs.hasObjCLifetime())
  return true;

// CVR qualifiers inconsistent or a superset.
return (ParamQs.getCVRQualifiers() & ~ArgQs.getCVRQualifiers()) != 0;
1137}

1139/// Compare types for equality with respect to possibly compatible
1140/// function types (noreturn adjustment, implicit calling conventions). If any
1141/// of parameter and argument is not a function, just perform type comparison.
1142///
1143/// \param Param the template parameter type.
1144///
1145/// \param Arg the argument type.
1146bool Sema::isSameOrCompatibleFunctionType(CanQualType Param,
                                        CanQualType Arg) {
const FunctionType *ParamFunction = Param->getAs<FunctionType>(),
                   *ArgFunction   = Arg->getAs<FunctionType>();

// Just compare if not functions.
if (!ParamFunction || !ArgFunction)
  return Param == Arg;

// Noreturn and noexcept adjustment.
QualType AdjustedParam;
if (IsFunctionConversion(Param, Arg, AdjustedParam))
  return Arg == Context.getCanonicalType(AdjustedParam);

// FIXME: Compatible calling conventions.

return Param == Arg;
1163}

1165/// Get the index of the first template parameter that was originally from the
1166/// innermost template-parameter-list. This is 0 except when we concatenate
1167/// the template parameter lists of a class template and a constructor template
1168/// when forming an implicit deduction guide.
1169static unsigned getFirstInnerIndex(FunctionTemplateDecl *FTD) {
auto *Guide = dyn_cast<CXXDeductionGuideDecl>(FTD->getTemplatedDecl());
if (!Guide || !Guide->isImplicit())
  return 0;
return Guide->getDeducedTemplate()->getTemplateParameters()->size();
1174}

1176/// Determine whether a type denotes a forwarding reference.
1177static bool isForwardingReference(QualType Param, unsigned FirstInnerIndex) {
// C++1z [temp.deduct.call]p3:
//   A forwarding reference is an rvalue reference to a cv-unqualified
//   template parameter that does not represent a template parameter of a
//   class template.
if (auto *ParamRef = Param->getAs<RValueReferenceType>()) {
  if (ParamRef->getPointeeType().getQualifiers())
    return false;
  auto *TypeParm = ParamRef->getPointeeType()->getAs<TemplateTypeParmType>();
  return TypeParm && TypeParm->getIndex() >= FirstInnerIndex;
}
return false;
1189}

1191/// Deduce the template arguments by comparing the parameter type and
1192/// the argument type (C++ [temp.deduct.type]).
1193///
1194/// \param S the semantic analysis object within which we are deducing
1195///
1196/// \param TemplateParams the template parameters that we are deducing
1197///
1198/// \param ParamIn the parameter type
1199///
1200/// \param ArgIn the argument type
1201///
1202/// \param Info information about the template argument deduction itself
1203///
1204/// \param Deduced the deduced template arguments
1205///
1206/// \param TDF bitwise OR of the TemplateDeductionFlags bits that describe
1207/// how template argument deduction is performed.
1208///
1209/// \param PartialOrdering Whether we're performing template argument deduction
1210/// in the context of partial ordering (C++0x [temp.deduct.partial]).
1211///
1212/// \returns the result of template argument deduction so far. Note that a
1213/// "success" result means that template argument deduction has not yet failed,
1214/// but it may still fail, later, for other reasons.
1215static Sema::TemplateDeductionResult
1216DeduceTemplateArgumentsByTypeMatch(Sema &S,
                                 TemplateParameterList *TemplateParams,
                                 QualType ParamIn, QualType ArgIn,
                                 TemplateDeductionInfo &Info,
                          SmallVectorImpl<DeducedTemplateArgument> &Deduced,
                                 unsigned TDF,
                                 bool PartialOrdering,
                                 bool DeducedFromArrayBound) {
// We only want to look at the canonical types, since typedefs and
// sugar are not part of template argument deduction.
QualType Param = S.Context.getCanonicalType(ParamIn);
QualType Arg = S.Context.getCanonicalType(ArgIn);

// If the argument type is a pack expansion, look at its pattern.
// This isn't explicitly called out
if (const PackExpansionType *ArgExpansion
                                          = dyn_cast<PackExpansionType>(Arg))
  Arg = ArgExpansion->getPattern();

if (PartialOrdering) {
  // C++11 [temp.deduct.partial]p5:
  //   Before the partial ordering is done, certain transformations are
  //   performed on the types used for partial ordering:
  //     - If P is a reference type, P is replaced by the type referred to.
  const ReferenceType *ParamRef = Param->getAs<ReferenceType>();
  if (ParamRef)
    Param = ParamRef->getPointeeType();

  //     - If A is a reference type, A is replaced by the type referred to.
  const ReferenceType *ArgRef = Arg->getAs<ReferenceType>();
  if (ArgRef)
    Arg = ArgRef->getPointeeType();

  if (ParamRef && ArgRef && S.Context.hasSameUnqualifiedType(Param, Arg)) {
    // C++11 [temp.deduct.partial]p9:
    //   If, for a given type, deduction succeeds in both directions (i.e.,
    //   the types are identical after the transformations above) and both
    //   P and A were reference types [...]:
    //     - if [one type] was an lvalue reference and [the other type] was
    //       not, [the other type] is not considered to be at least as
    //       specialized as [the first type]
    //     - if [one type] is more cv-qualified than [the other type],
    //       [the other type] is not considered to be at least as specialized
    //       as [the first type]
    // Objective-C ARC adds:
    //     - [one type] has non-trivial lifetime, [the other type] has
    //       __unsafe_unretained lifetime, and the types are otherwise
    //       identical
    //
    // A is "considered to be at least as specialized" as P iff deduction
    // succeeds, so we model this as a deduction failure. Note that
    // [the first type] is P and [the other type] is A here; the standard
    // gets this backwards.
    Qualifiers ParamQuals = Param.getQualifiers();
    Qualifiers ArgQuals = Arg.getQualifiers();
    if ((ParamRef->isLValueReferenceType() &&
         !ArgRef->isLValueReferenceType()) ||
        ParamQuals.isStrictSupersetOf(ArgQuals) ||
        (ParamQuals.hasNonTrivialObjCLifetime() &&
         ArgQuals.getObjCLifetime() == Qualifiers::OCL_ExplicitNone &&
         ParamQuals.withoutObjCLifetime() ==
             ArgQuals.withoutObjCLifetime())) {
      Info.FirstArg = TemplateArgument(ParamIn);
      Info.SecondArg = TemplateArgument(ArgIn);
      return Sema::TDK_NonDeducedMismatch;
    }
  }

  // C++11 [temp.deduct.partial]p7:
  //   Remove any top-level cv-qualifiers:
  //     - If P is a cv-qualified type, P is replaced by the cv-unqualified
  //       version of P.
  Param = Param.getUnqualifiedType();
  //     - If A is a cv-qualified type, A is replaced by the cv-unqualified
  //       version of A.
  Arg = Arg.getUnqualifiedType();
} else {
  // C++0x [temp.deduct.call]p4 bullet 1:
  //   - If the original P is a reference type, the deduced A (i.e., the type
  //     referred to by the reference) can be more cv-qualified than the
  //     transformed A.
  if (TDF & TDF_ParamWithReferenceType) {
    Qualifiers Quals;
    QualType UnqualParam = S.Context.getUnqualifiedArrayType(Param, Quals);
    Quals.setCVRQualifiers(Quals.getCVRQualifiers() &
                           Arg.getCVRQualifiers());
    Param = S.Context.getQualifiedType(UnqualParam, Quals);
  }

  if ((TDF & TDF_TopLevelParameterTypeList) && !Param->isFunctionType()) {
    // C++0x [temp.deduct.type]p10:
    //   If P and A are function types that originated from deduction when
    //   taking the address of a function template (14.8.2.2) or when deducing
    //   template arguments from a function declaration (14.8.2.6) and Pi and
    //   Ai are parameters of the top-level parameter-type-list of P and A,
    //   respectively, Pi is adjusted if it is a forwarding reference and Ai
    //   is an lvalue reference, in
    //   which case the type of Pi is changed to be the template parameter
    //   type (i.e., T&& is changed to simply T). [ Note: As a result, when
    //   Pi is T&& and Ai is X&, the adjusted Pi will be T, causing T to be
    //   deduced as X&. - end note ]
    TDF &= ~TDF_TopLevelParameterTypeList;
    if (isForwardingReference(Param, 0) && Arg->isLValueReferenceType())
      Param = Param->getPointeeType();
  }
}

// C++ [temp.deduct.type]p9:
//   A template type argument T, a template template argument TT or a
//   template non-type argument i can be deduced if P and A have one of
//   the following forms:
//
//     T
//     cv-list T
if (const TemplateTypeParmType *TemplateTypeParm
      = Param->getAs<TemplateTypeParmType>()) {
  // Just skip any attempts to deduce from a placeholder type or a parameter
  // at a different depth.
  if (Arg->isPlaceholderType() ||
      Info.getDeducedDepth() != TemplateTypeParm->getDepth())
    return Sema::TDK_Success;

  unsigned Index = TemplateTypeParm->getIndex();
  bool RecanonicalizeArg = false;

  // If the argument type is an array type, move the qualifiers up to the
  // top level, so they can be matched with the qualifiers on the parameter.
  if (isa<ArrayType>(Arg)) {
    Qualifiers Quals;
    Arg = S.Context.getUnqualifiedArrayType(Arg, Quals);
    if (Quals) {
      Arg = S.Context.getQualifiedType(Arg, Quals);
      RecanonicalizeArg = true;
    }
  }

  // The argument type can not be less qualified than the parameter
  // type.
  if (!(TDF & TDF_IgnoreQualifiers) &&
      hasInconsistentOrSupersetQualifiersOf(Param, Arg)) {
    Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index));
    Info.FirstArg = TemplateArgument(Param);
    Info.SecondArg = TemplateArgument(Arg);
    return Sema::TDK_Underqualified;
  }

  // Do not match a function type with a cv-qualified type.
  // http://www.open-std.org/jtc1/sc22/wg21/docs/cwg_active.html#1584
  if (Arg->isFunctionType() && Param.hasQualifiers()) {
    return Sema::TDK_NonDeducedMismatch;
  }

  assert(TemplateTypeParm->getDepth() == Info.getDeducedDepth() &&((TemplateTypeParm->getDepth() == Info.getDeducedDepth() &&
 "saw template type parameter with wrong depth") ? static_cast
<void> (0) : __assert_fail ("TemplateTypeParm->getDepth() == Info.getDeducedDepth() && \"saw template type parameter with wrong depth\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1369, __PRETTY_FUNCTION__))
         "saw template type parameter with wrong depth")((TemplateTypeParm->getDepth() == Info.getDeducedDepth() &&
 "saw template type parameter with wrong depth") ? static_cast
<void> (0) : __assert_fail ("TemplateTypeParm->getDepth() == Info.getDeducedDepth() && \"saw template type parameter with wrong depth\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1369, __PRETTY_FUNCTION__));
  assert(Arg != S.Context.OverloadTy && "Unresolved overloaded function")((Arg != S.Context.OverloadTy && "Unresolved overloaded function"
) ? static_cast<void> (0) : __assert_fail ("Arg != S.Context.OverloadTy && \"Unresolved overloaded function\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1370, __PRETTY_FUNCTION__));
  QualType DeducedType = Arg;

  // Remove any qualifiers on the parameter from the deduced type.
  // We checked the qualifiers for consistency above.
  Qualifiers DeducedQs = DeducedType.getQualifiers();
  Qualifiers ParamQs = Param.getQualifiers();
  DeducedQs.removeCVRQualifiers(ParamQs.getCVRQualifiers());
  if (ParamQs.hasObjCGCAttr())
    DeducedQs.removeObjCGCAttr();
  if (ParamQs.hasAddressSpace())
    DeducedQs.removeAddressSpace();
  if (ParamQs.hasObjCLifetime())
    DeducedQs.removeObjCLifetime();

  // Objective-C ARC:
  //   If template deduction would produce a lifetime qualifier on a type
  //   that is not a lifetime type, template argument deduction fails.
  if (ParamQs.hasObjCLifetime() && !DeducedType->isObjCLifetimeType() &&
      !DeducedType->isDependentType()) {
    Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index));
    Info.FirstArg = TemplateArgument(Param);
    Info.SecondArg = TemplateArgument(Arg);
    return Sema::TDK_Underqualified;
  }

  // Objective-C ARC:
  //   If template deduction would produce an argument type with lifetime type
  //   but no lifetime qualifier, the __strong lifetime qualifier is inferred.
  if (S.getLangOpts().ObjCAutoRefCount &&
      DeducedType->isObjCLifetimeType() &&
      !DeducedQs.hasObjCLifetime())
    DeducedQs.setObjCLifetime(Qualifiers::OCL_Strong);

  DeducedType = S.Context.getQualifiedType(DeducedType.getUnqualifiedType(),
                                           DeducedQs);

  if (RecanonicalizeArg)
    DeducedType = S.Context.getCanonicalType(DeducedType);

  DeducedTemplateArgument NewDeduced(DeducedType, DeducedFromArrayBound);
  DeducedTemplateArgument Result = checkDeducedTemplateArguments(S.Context,
                                                               Deduced[Index],
                                                                 NewDeduced);
  if (Result.isNull()) {
    Info.Param = cast<TemplateTypeParmDecl>(TemplateParams->getParam(Index));
    Info.FirstArg = Deduced[Index];
    Info.SecondArg = NewDeduced;
    return Sema::TDK_Inconsistent;
  }

  Deduced[Index] = Result;
  return Sema::TDK_Success;
}

// Set up the template argument deduction information for a failure.
Info.FirstArg = TemplateArgument(ParamIn);
Info.SecondArg = TemplateArgument(ArgIn);

// If the parameter is an already-substituted template parameter
// pack, do nothing: we don't know which of its arguments to look
// at, so we have to wait until all of the parameter packs in this
// expansion have arguments.
if (isa<SubstTemplateTypeParmPackType>(Param))
  return Sema::TDK_Success;

// Check the cv-qualifiers on the parameter and argument types.
CanQualType CanParam = S.Context.getCanonicalType(Param);
CanQualType CanArg = S.Context.getCanonicalType(Arg);
if (!(TDF & TDF_IgnoreQualifiers)) {
  if (TDF & TDF_ParamWithReferenceType) {
    if (hasInconsistentOrSupersetQualifiersOf(Param, Arg))
      return Sema::TDK_NonDeducedMismatch;
  } else if (TDF & TDF_ArgWithReferenceType) {
    // C++ [temp.deduct.conv]p4:
    //   If the original A is a reference type, A can be more cv-qualified
    //   than the deduced A
    if (!Arg.getQualifiers().compatiblyIncludes(Param.getQualifiers()))
      return Sema::TDK_NonDeducedMismatch;

    // Strip out all extra qualifiers from the argument to figure out the
    // type we're converting to, prior to the qualification conversion.
    Qualifiers Quals;
    Arg = S.Context.getUnqualifiedArrayType(Arg, Quals);
    Arg = S.Context.getQualifiedType(Arg, Param.getQualifiers());
  } else if (!IsPossiblyOpaquelyQualifiedType(Param)) {
    if (Param.getCVRQualifiers() != Arg.getCVRQualifiers())
      return Sema::TDK_NonDeducedMismatch;
  }

  // If the parameter type is not dependent, there is nothing to deduce.
  if (!Param->isDependentType()) {
    if (!(TDF & TDF_SkipNonDependent)) {
      bool NonDeduced =
          (TDF & TDF_AllowCompatibleFunctionType)
              ? !S.isSameOrCompatibleFunctionType(CanParam, CanArg)
              : Param != Arg;
      if (NonDeduced) {
        return Sema::TDK_NonDeducedMismatch;
      }
    }
    return Sema::TDK_Success;
  }
} else if (!Param->isDependentType()) {
  CanQualType ParamUnqualType = CanParam.getUnqualifiedType(),
              ArgUnqualType = CanArg.getUnqualifiedType();
  bool Success =
      (TDF & TDF_AllowCompatibleFunctionType)
          ? S.isSameOrCompatibleFunctionType(ParamUnqualType, ArgUnqualType)
          : ParamUnqualType == ArgUnqualType;
  if (Success)
    return Sema::TDK_Success;
}

switch (Param->getTypeClass()) {
  // Non-canonical types cannot appear here.
1486#define NON_CANONICAL_TYPE(Class, Base) \
case Type::Class: llvm_unreachable("deducing non-canonical type: " #Class)::llvm::llvm_unreachable_internal("deducing non-canonical type: "
 #Class, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1487);
1488#define TYPE(Class, Base)
1489#include "clang/AST/TypeNodes.inc"

  case Type::TemplateTypeParm:
  case Type::SubstTemplateTypeParmPack:
    llvm_unreachable("Type nodes handled above")::llvm::llvm_unreachable_internal("Type nodes handled above",
 "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1493);

  // These types cannot be dependent, so simply check whether the types are
  // the same.
  case Type::Builtin:
  case Type::VariableArray:
  case Type::Vector:
  case Type::FunctionNoProto:
  case Type::Record:
  case Type::Enum:
  case Type::ObjCObject:
  case Type::ObjCInterface:
  case Type::ObjCObjectPointer:
    if (TDF & TDF_SkipNonDependent)
      return Sema::TDK_Success;

    if (TDF & TDF_IgnoreQualifiers) {
      Param = Param.getUnqualifiedType();
      Arg = Arg.getUnqualifiedType();
    }

    return Param == Arg? Sema::TDK_Success : Sema::TDK_NonDeducedMismatch;

  //     _Complex T   [placeholder extension]
  case Type::Complex:
    if (const ComplexType *ComplexArg = Arg->getAs<ComplexType>())
      return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                  cast<ComplexType>(Param)->getElementType(),
                                  ComplexArg->getElementType(),
                                  Info, Deduced, TDF);

    return Sema::TDK_NonDeducedMismatch;

  //     _Atomic T   [extension]
  case Type::Atomic:
    if (const AtomicType *AtomicArg = Arg->getAs<AtomicType>())
      return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                     cast<AtomicType>(Param)->getValueType(),
                                     AtomicArg->getValueType(),
                                     Info, Deduced, TDF);

    return Sema::TDK_NonDeducedMismatch;

  //     T *
  case Type::Pointer: {
    QualType PointeeType;
    if (const PointerType *PointerArg = Arg->getAs<PointerType>()) {
      PointeeType = PointerArg->getPointeeType();
    } else if (const ObjCObjectPointerType *PointerArg
                 = Arg->getAs<ObjCObjectPointerType>()) {
      PointeeType = PointerArg->getPointeeType();
    } else {
      return Sema::TDK_NonDeducedMismatch;
    }

    unsigned SubTDF = TDF & (TDF_IgnoreQualifiers | TDF_DerivedClass);
    return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                   cast<PointerType>(Param)->getPointeeType(),
                                   PointeeType,
                                   Info, Deduced, SubTDF);
  }

  //     T &
  case Type::LValueReference: {
    const LValueReferenceType *ReferenceArg =
        Arg->getAs<LValueReferenceType>();
    if (!ReferenceArg)
      return Sema::TDK_NonDeducedMismatch;

    return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                         cast<LValueReferenceType>(Param)->getPointeeType(),
                         ReferenceArg->getPointeeType(), Info, Deduced, 0);
  }

  //     T && [C++0x]
  case Type::RValueReference: {
    const RValueReferenceType *ReferenceArg =
        Arg->getAs<RValueReferenceType>();
    if (!ReferenceArg)
      return Sema::TDK_NonDeducedMismatch;

    return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                           cast<RValueReferenceType>(Param)->getPointeeType(),
                           ReferenceArg->getPointeeType(),
                           Info, Deduced, 0);
  }

  //     T [] (implied, but not stated explicitly)
  case Type::IncompleteArray: {
    const IncompleteArrayType *IncompleteArrayArg =
      S.Context.getAsIncompleteArrayType(Arg);
    if (!IncompleteArrayArg)
      return Sema::TDK_NonDeducedMismatch;

    unsigned SubTDF = TDF & TDF_IgnoreQualifiers;
    return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                  S.Context.getAsIncompleteArrayType(Param)->getElementType(),
                  IncompleteArrayArg->getElementType(),
                  Info, Deduced, SubTDF);
  }

  //     T [integer-constant]
  case Type::ConstantArray: {
    const ConstantArrayType *ConstantArrayArg =
      S.Context.getAsConstantArrayType(Arg);
    if (!ConstantArrayArg)
      return Sema::TDK_NonDeducedMismatch;

    const ConstantArrayType *ConstantArrayParm =
      S.Context.getAsConstantArrayType(Param);
    if (ConstantArrayArg->getSize() != ConstantArrayParm->getSize())
      return Sema::TDK_NonDeducedMismatch;

    unsigned SubTDF = TDF & TDF_IgnoreQualifiers;
    return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                         ConstantArrayParm->getElementType(),
                                         ConstantArrayArg->getElementType(),
                                         Info, Deduced, SubTDF);
  }

  //     type [i]
  case Type::DependentSizedArray: {
    const ArrayType *ArrayArg = S.Context.getAsArrayType(Arg);
    if (!ArrayArg)
      return Sema::TDK_NonDeducedMismatch;

    unsigned SubTDF = TDF & TDF_IgnoreQualifiers;

    // Check the element type of the arrays
    const DependentSizedArrayType *DependentArrayParm
      = S.Context.getAsDependentSizedArrayType(Param);
    if (Sema::TemplateDeductionResult Result
          = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                        DependentArrayParm->getElementType(),
                                        ArrayArg->getElementType(),
                                        Info, Deduced, SubTDF))
      return Result;

    // Determine the array bound is something we can deduce.
    NonTypeTemplateParmDecl *NTTP
      = getDeducedParameterFromExpr(Info, DependentArrayParm->getSizeExpr());
    if (!NTTP)
      return Sema::TDK_Success;

    // We can perform template argument deduction for the given non-type
    // template parameter.
    assert(NTTP->getDepth() == Info.getDeducedDepth() &&((NTTP->getDepth() == Info.getDeducedDepth() && "saw non-type template parameter with wrong depth"
) ? static_cast<void> (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"saw non-type template parameter with wrong depth\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1640, __PRETTY_FUNCTION__))
           "saw non-type template parameter with wrong depth")((NTTP->getDepth() == Info.getDeducedDepth() && "saw non-type template parameter with wrong depth"
) ? static_cast<void> (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"saw non-type template parameter with wrong depth\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1640, __PRETTY_FUNCTION__));
    if (const ConstantArrayType *ConstantArrayArg
          = dyn_cast<ConstantArrayType>(ArrayArg)) {
      llvm::APSInt Size(ConstantArrayArg->getSize());
      return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, Size,
                                           S.Context.getSizeType(),
                                           /*ArrayBound=*/true,
                                           Info, Deduced);
    }
    if (const DependentSizedArrayType *DependentArrayArg
          = dyn_cast<DependentSizedArrayType>(ArrayArg))
      if (DependentArrayArg->getSizeExpr())
        return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
                                             DependentArrayArg->getSizeExpr(),
                                             Info, Deduced);

    // Incomplete type does not match a dependently-sized array type
    return Sema::TDK_NonDeducedMismatch;
  }

  //     type(*)(T)
  //     T(*)()
  //     T(*)(T)
  case Type::FunctionProto: {
    unsigned SubTDF = TDF & TDF_TopLevelParameterTypeList;
    const FunctionProtoType *FunctionProtoArg =
      dyn_cast<FunctionProtoType>(Arg);
    if (!FunctionProtoArg)
      return Sema::TDK_NonDeducedMismatch;

    const FunctionProtoType *FunctionProtoParam =
      cast<FunctionProtoType>(Param);

    if (FunctionProtoParam->getMethodQuals()
          != FunctionProtoArg->getMethodQuals() ||
        FunctionProtoParam->getRefQualifier()
          != FunctionProtoArg->getRefQualifier() ||
        FunctionProtoParam->isVariadic() != FunctionProtoArg->isVariadic())
      return Sema::TDK_NonDeducedMismatch;

    // Check return types.
    if (auto Result = DeduceTemplateArgumentsByTypeMatch(
            S, TemplateParams, FunctionProtoParam->getReturnType(),
            FunctionProtoArg->getReturnType(), Info, Deduced, 0))
      return Result;

    // Check parameter types.
    if (auto Result = DeduceTemplateArguments(
            S, TemplateParams, FunctionProtoParam->param_type_begin(),
            FunctionProtoParam->getNumParams(),
            FunctionProtoArg->param_type_begin(),
            FunctionProtoArg->getNumParams(), Info, Deduced, SubTDF))
      return Result;

    if (TDF & TDF_AllowCompatibleFunctionType)
      return Sema::TDK_Success;

    // FIXME: Per core-2016/10/1019 (no corresponding core issue yet), permit
    // deducing through the noexcept-specifier if it's part of the canonical
    // type. libstdc++ relies on this.
    Expr *NoexceptExpr = FunctionProtoParam->getNoexceptExpr();
    if (NonTypeTemplateParmDecl *NTTP =
        NoexceptExpr ? getDeducedParameterFromExpr(Info, NoexceptExpr)
                     : nullptr) {
      assert(NTTP->getDepth() == Info.getDeducedDepth() &&((NTTP->getDepth() == Info.getDeducedDepth() && "saw non-type template parameter with wrong depth"
) ? static_cast<void> (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"saw non-type template parameter with wrong depth\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1705, __PRETTY_FUNCTION__))
             "saw non-type template parameter with wrong depth")((NTTP->getDepth() == Info.getDeducedDepth() && "saw non-type template parameter with wrong depth"
) ? static_cast<void> (0) : __assert_fail ("NTTP->getDepth() == Info.getDeducedDepth() && \"saw non-type template parameter with wrong depth\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1705, __PRETTY_FUNCTION__));

      llvm::APSInt Noexcept(1);
      switch (FunctionProtoArg->canThrow()) {
      case CT_Cannot:
        Noexcept = 1;
        LLVM_FALLTHROUGH[[gnu::fallthrough]];

      case CT_Can:
        // We give E in noexcept(E) the "deduced from array bound" treatment.
        // FIXME: Should we?
        return DeduceNonTypeTemplateArgument(
            S, TemplateParams, NTTP, Noexcept, S.Context.BoolTy,
            /*ArrayBound*/true, Info, Deduced);

      case CT_Dependent:
        if (Expr *ArgNoexceptExpr = FunctionProtoArg->getNoexceptExpr())
          return DeduceNonTypeTemplateArgument(
              S, TemplateParams, NTTP, ArgNoexceptExpr, Info, Deduced);
        // Can't deduce anything from throw(T...).
        break;
      }
    }
    // FIXME: Detect non-deduced exception specification mismatches?
    //
    // Careful about [temp.deduct.call] and [temp.deduct.conv], which allow
    // top-level differences in noexcept-specifications.

    return Sema::TDK_Success;
  }

  case Type::InjectedClassName:
    // Treat a template's injected-class-name as if the template
    // specialization type had been used.
    Param = cast<InjectedClassNameType>(Param)
      ->getInjectedSpecializationType();
    assert(isa<TemplateSpecializationType>(Param) &&((isa<TemplateSpecializationType>(Param) && "injected class name is not a template specialization type"
) ? static_cast<void> (0) : __assert_fail ("isa<TemplateSpecializationType>(Param) && \"injected class name is not a template specialization type\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1742, __PRETTY_FUNCTION__))
           "injected class name is not a template specialization type")((isa<TemplateSpecializationType>(Param) && "injected class name is not a template specialization type"
) ? static_cast<void> (0) : __assert_fail ("isa<TemplateSpecializationType>(Param) && \"injected class name is not a template specialization type\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1742, __PRETTY_FUNCTION__));
    LLVM_FALLTHROUGH[[gnu::fallthrough]];

  //     template-name<T> (where template-name refers to a class template)
  //     template-name<i>
  //     TT<T>
  //     TT<i>
  //     TT<>
  case Type::TemplateSpecialization: {
    const TemplateSpecializationType *SpecParam =
        cast<TemplateSpecializationType>(Param);

    // When Arg cannot be a derived class, we can just try to deduce template
    // arguments from the template-id.
    const RecordType *RecordT = Arg->getAs<RecordType>();
    if (!(TDF & TDF_DerivedClass) || !RecordT)
      return DeduceTemplateArguments(S, TemplateParams, SpecParam, Arg, Info,
                                     Deduced);

    SmallVector<DeducedTemplateArgument, 8> DeducedOrig(Deduced.begin(),
                                                        Deduced.end());

    Sema::TemplateDeductionResult Result = DeduceTemplateArguments(
        S, TemplateParams, SpecParam, Arg, Info, Deduced);

    if (Result == Sema::TDK_Success)
      return Result;

    // We cannot inspect base classes as part of deduction when the type
    // is incomplete, so either instantiate any templates necessary to
    // complete the type, or skip over it if it cannot be completed.
    if (!S.isCompleteType(Info.getLocation(), Arg))
      return Result;

    // C++14 [temp.deduct.call] p4b3:
    //   If P is a class and P has the form simple-template-id, then the
    //   transformed A can be a derived class of the deduced A. Likewise if
    //   P is a pointer to a class of the form simple-template-id, the
    //   transformed A can be a pointer to a derived class pointed to by the
    //   deduced A.
    //
    //   These alternatives are considered only if type deduction would
    //   otherwise fail. If they yield more than one possible deduced A, the
    //   type deduction fails.

    // Reset the incorrectly deduced argument from above.
    Deduced = DeducedOrig;

    // Use data recursion to crawl through the list of base classes.
    // Visited contains the set of nodes we have already visited, while
    // ToVisit is our stack of records that we still need to visit.
    llvm::SmallPtrSet<const RecordType *, 8> Visited;
    SmallVector<const RecordType *, 8> ToVisit;
    ToVisit.push_back(RecordT);
    bool Successful = false;
    SmallVector<DeducedTemplateArgument, 8> SuccessfulDeduced;
    while (!ToVisit.empty()) {
      // Retrieve the next class in the inheritance hierarchy.
      const RecordType *NextT = ToVisit.pop_back_val();

      // If we have already seen this type, skip it.
      if (!Visited.insert(NextT).second)
        continue;

      // If this is a base class, try to perform template argument
      // deduction from it.
      if (NextT != RecordT) {
        TemplateDeductionInfo BaseInfo(Info.getLocation());
        Sema::TemplateDeductionResult BaseResult =
            DeduceTemplateArguments(S, TemplateParams, SpecParam,
                                    QualType(NextT, 0), BaseInfo, Deduced);

        // If template argument deduction for this base was successful,
        // note that we had some success. Otherwise, ignore any deductions
        // from this base class.
        if (BaseResult == Sema::TDK_Success) {
          // If we've already seen some success, then deduction fails due to
          // an ambiguity (temp.deduct.call p5).
          if (Successful)
            return Sema::TDK_MiscellaneousDeductionFailure;

          Successful = true;
          std::swap(SuccessfulDeduced, Deduced);

          Info.Param = BaseInfo.Param;
          Info.FirstArg = BaseInfo.FirstArg;
          Info.SecondArg = BaseInfo.SecondArg;
        }

        Deduced = DeducedOrig;
      }

      // Visit base classes
      CXXRecordDecl *Next = cast<CXXRecordDecl>(NextT->getDecl());
      for (const auto &Base : Next->bases()) {
        assert(Base.getType()->isRecordType() &&((Base.getType()->isRecordType() && "Base class that isn't a record?"
) ? static_cast<void> (0) : __assert_fail ("Base.getType()->isRecordType() && \"Base class that isn't a record?\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1838, __PRETTY_FUNCTION__))
               "Base class that isn't a record?")((Base.getType()->isRecordType() && "Base class that isn't a record?"
) ? static_cast<void> (0) : __assert_fail ("Base.getType()->isRecordType() && \"Base class that isn't a record?\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 1838, __PRETTY_FUNCTION__));
        ToVisit.push_back(Base.getType()->getAs<RecordType>());
      }
    }

    if (Successful) {
      std::swap(SuccessfulDeduced, Deduced);
      return Sema::TDK_Success;
    }

    return Result;
  }

  //     T type::*
  //     T T::*
  //     T (type::*)()
  //     type (T::*)()
  //     type (type::*)(T)
  //     type (T::*)(T)
  //     T (type::*)(T)
  //     T (T::*)()
  //     T (T::*)(T)
  case Type::MemberPointer: {
    const MemberPointerType *MemPtrParam = cast<MemberPointerType>(Param);
    const MemberPointerType *MemPtrArg = dyn_cast<MemberPointerType>(Arg);
    if (!MemPtrArg)
      return Sema::TDK_NonDeducedMismatch;

    QualType ParamPointeeType = MemPtrParam->getPointeeType();
    if (ParamPointeeType->isFunctionType())
      S.adjustMemberFunctionCC(ParamPointeeType, /*IsStatic=*/true,
                               /*IsCtorOrDtor=*/false, Info.getLocation());
    QualType ArgPointeeType = MemPtrArg->getPointeeType();
    if (ArgPointeeType->isFunctionType())
      S.adjustMemberFunctionCC(ArgPointeeType, /*IsStatic=*/true,
                               /*IsCtorOrDtor=*/false, Info.getLocation());

    if (Sema::TemplateDeductionResult Result
          = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                               ParamPointeeType,
                                               ArgPointeeType,
                                               Info, Deduced,
                                               TDF & TDF_IgnoreQualifiers))
      return Result;

    return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                         QualType(MemPtrParam->getClass(), 0),
                                         QualType(MemPtrArg->getClass(), 0),
                                         Info, Deduced,
                                         TDF & TDF_IgnoreQualifiers);
  }

  //     (clang extension)
  //
  //     type(^)(T)
  //     T(^)()
  //     T(^)(T)
  case Type::BlockPointer: {
    const BlockPointerType *BlockPtrParam = cast<BlockPointerType>(Param);
    const BlockPointerType *BlockPtrArg = dyn_cast<BlockPointerType>(Arg);

    if (!BlockPtrArg)
      return Sema::TDK_NonDeducedMismatch;

    return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                              BlockPtrParam->getPointeeType(),
                                              BlockPtrArg->getPointeeType(),
                                              Info, Deduced, 0);
  }

  //     (clang extension)
  //
  //     T __attribute__(((ext_vector_type(<integral constant>))))
  case Type::ExtVector: {
    const ExtVectorType *VectorParam = cast<ExtVectorType>(Param);
    if (const ExtVectorType *VectorArg = dyn_cast<ExtVectorType>(Arg)) {
      // Make sure that the vectors have the same number of elements.
      if (VectorParam->getNumElements() != VectorArg->getNumElements())
        return Sema::TDK_NonDeducedMismatch;

      // Perform deduction on the element types.
      return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                                VectorParam->getElementType(),
                                                VectorArg->getElementType(),
                                                Info, Deduced, TDF);
    }

    if (const DependentSizedExtVectorType *VectorArg
                              = dyn_cast<DependentSizedExtVectorType>(Arg)) {
      // We can't check the number of elements, since the argument has a
      // dependent number of elements. This can only occur during partial
      // ordering.

      // Perform deduction on the element types.
      return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                                VectorParam->getElementType(),
                                                VectorArg->getElementType(),
                                                Info, Deduced, TDF);
    }

    return Sema::TDK_NonDeducedMismatch;
  }

  case Type::DependentVector: {
    const auto *VectorParam = cast<DependentVectorType>(Param);

    if (const auto *VectorArg = dyn_cast<VectorType>(Arg)) {
      // Perform deduction on the element types.
      if (Sema::TemplateDeductionResult Result =
              DeduceTemplateArgumentsByTypeMatch(
                  S, TemplateParams, VectorParam->getElementType(),
                  VectorArg->getElementType(), Info, Deduced, TDF))
        return Result;

      // Perform deduction on the vector size, if we can.
      NonTypeTemplateParmDecl *NTTP =
          getDeducedParameterFromExpr(Info, VectorParam->getSizeExpr());
      if (!NTTP)
        return Sema::TDK_Success;

      llvm::APSInt ArgSize(S.Context.getTypeSize(S.Context.IntTy), false);
      ArgSize = VectorArg->getNumElements();
      // Note that we use the "array bound" rules here; just like in that
      // case, we don't have any particular type for the vector size, but
      // we can provide one if necessary.
      return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, ArgSize,
                                           S.Context.UnsignedIntTy, true,
                                           Info, Deduced);
    }

    if (const auto *VectorArg = dyn_cast<DependentVectorType>(Arg)) {
      // Perform deduction on the element types.
      if (Sema::TemplateDeductionResult Result =
              DeduceTemplateArgumentsByTypeMatch(
                  S, TemplateParams, VectorParam->getElementType(),
                  VectorArg->getElementType(), Info, Deduced, TDF))
        return Result;

      // Perform deduction on the vector size, if we can.
      NonTypeTemplateParmDecl *NTTP = getDeducedParameterFromExpr(
          Info, VectorParam->getSizeExpr());
      if (!NTTP)
        return Sema::TDK_Success;

      return DeduceNonTypeTemplateArgument(
          S, TemplateParams, NTTP, VectorArg->getSizeExpr(), Info, Deduced);
    }

    return Sema::TDK_NonDeducedMismatch;
  }

  //     (clang extension)
  //
  //     T __attribute__(((ext_vector_type(N))))
  case Type::DependentSizedExtVector: {
    const DependentSizedExtVectorType *VectorParam
      = cast<DependentSizedExtVectorType>(Param);

    if (const ExtVectorType *VectorArg = dyn_cast<ExtVectorType>(Arg)) {
      // Perform deduction on the element types.
      if (Sema::TemplateDeductionResult Result
            = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                                VectorParam->getElementType(),
                                                 VectorArg->getElementType(),
                                                 Info, Deduced, TDF))
        return Result;

      // Perform deduction on the vector size, if we can.
      NonTypeTemplateParmDecl *NTTP
        = getDeducedParameterFromExpr(Info, VectorParam->getSizeExpr());
      if (!NTTP)
        return Sema::TDK_Success;

      llvm::APSInt ArgSize(S.Context.getTypeSize(S.Context.IntTy), false);
      ArgSize = VectorArg->getNumElements();
      // Note that we use the "array bound" rules here; just like in that
      // case, we don't have any particular type for the vector size, but
      // we can provide one if necessary.
      return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP, ArgSize,
                                           S.Context.IntTy, true, Info,
                                           Deduced);
    }

    if (const DependentSizedExtVectorType *VectorArg
                              = dyn_cast<DependentSizedExtVectorType>(Arg)) {
      // Perform deduction on the element types.
      if (Sema::TemplateDeductionResult Result
          = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                               VectorParam->getElementType(),
                                               VectorArg->getElementType(),
                                               Info, Deduced, TDF))
        return Result;

      // Perform deduction on the vector size, if we can.
      NonTypeTemplateParmDecl *NTTP
        = getDeducedParameterFromExpr(Info, VectorParam->getSizeExpr());
      if (!NTTP)
        return Sema::TDK_Success;

      return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
                                           VectorArg->getSizeExpr(),
                                           Info, Deduced);
    }

    return Sema::TDK_NonDeducedMismatch;
  }

  //     (clang extension)
  //
  //     T __attribute__(((address_space(N))))
  case Type::DependentAddressSpace: {
    const DependentAddressSpaceType *AddressSpaceParam =
        cast<DependentAddressSpaceType>(Param);

    if (const DependentAddressSpaceType *AddressSpaceArg =
            dyn_cast<DependentAddressSpaceType>(Arg)) {
      // Perform deduction on the pointer type.
      if (Sema::TemplateDeductionResult Result =
              DeduceTemplateArgumentsByTypeMatch(
                  S, TemplateParams, AddressSpaceParam->getPointeeType(),
                  AddressSpaceArg->getPointeeType(), Info, Deduced, TDF))
        return Result;

      // Perform deduction on the address space, if we can.
      NonTypeTemplateParmDecl *NTTP = getDeducedParameterFromExpr(
          Info, AddressSpaceParam->getAddrSpaceExpr());
      if (!NTTP)
        return Sema::TDK_Success;

      return DeduceNonTypeTemplateArgument(
          S, TemplateParams, NTTP, AddressSpaceArg->getAddrSpaceExpr(), Info,
          Deduced);
    }

    if (isTargetAddressSpace(Arg.getAddressSpace())) {
      llvm::APSInt ArgAddressSpace(S.Context.getTypeSize(S.Context.IntTy),
                                   false);
      ArgAddressSpace = toTargetAddressSpace(Arg.getAddressSpace());

      // Perform deduction on the pointer types.
      if (Sema::TemplateDeductionResult Result =
              DeduceTemplateArgumentsByTypeMatch(
                  S, TemplateParams, AddressSpaceParam->getPointeeType(),
                  S.Context.removeAddrSpaceQualType(Arg), Info, Deduced, TDF))
        return Result;

      // Perform deduction on the address space, if we can.
      NonTypeTemplateParmDecl *NTTP = getDeducedParameterFromExpr(
          Info, AddressSpaceParam->getAddrSpaceExpr());
      if (!NTTP)
        return Sema::TDK_Success;

      return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
                                           ArgAddressSpace, S.Context.IntTy,
                                           true, Info, Deduced);
    }

    return Sema::TDK_NonDeducedMismatch;
  }

  case Type::TypeOfExpr:
  case Type::TypeOf:
  case Type::DependentName:
  case Type::UnresolvedUsing:
  case Type::Decltype:
  case Type::UnaryTransform:
  case Type::Auto:
  case Type::DeducedTemplateSpecialization:
  case Type::DependentTemplateSpecialization:
  case Type::PackExpansion:
  case Type::Pipe:
    // No template argument deduction for these types
    return Sema::TDK_Success;
}

llvm_unreachable("Invalid Type Class!")::llvm::llvm_unreachable_internal("Invalid Type Class!", "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2113);
2114}

2116static Sema::TemplateDeductionResult
2117DeduceTemplateArguments(Sema &S,
                      TemplateParameterList *TemplateParams,
                      const TemplateArgument &Param,
                      TemplateArgument Arg,
                      TemplateDeductionInfo &Info,
                      SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
// If the template argument is a pack expansion, perform template argument
// deduction against the pattern of that expansion. This only occurs during
// partial ordering.
if (Arg.isPackExpansion())
  Arg = Arg.getPackExpansionPattern();

switch (Param.getKind()) {
case TemplateArgument::Null:
  llvm_unreachable("Null template argument in parameter list")::llvm::llvm_unreachable_internal("Null template argument in parameter list"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2131);

case TemplateArgument::Type:
  if (Arg.getKind() == TemplateArgument::Type)
    return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams,
                                              Param.getAsType(),
                                              Arg.getAsType(),
                                              Info, Deduced, 0);
  Info.FirstArg = Param;
  Info.SecondArg = Arg;
  return Sema::TDK_NonDeducedMismatch;

case TemplateArgument::Template:
  if (Arg.getKind() == TemplateArgument::Template)
    return DeduceTemplateArguments(S, TemplateParams,
                                   Param.getAsTemplate(),
                                   Arg.getAsTemplate(), Info, Deduced);
  Info.FirstArg = Param;
  Info.SecondArg = Arg;
  return Sema::TDK_NonDeducedMismatch;

case TemplateArgument::TemplateExpansion:
  llvm_unreachable("caller should handle pack expansions")::llvm::llvm_unreachable_internal("caller should handle pack expansions"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2153);

case TemplateArgument::Declaration:
  if (Arg.getKind() == TemplateArgument::Declaration &&
      isSameDeclaration(Param.getAsDecl(), Arg.getAsDecl()))
    return Sema::TDK_Success;

  Info.FirstArg = Param;
  Info.SecondArg = Arg;
  return Sema::TDK_NonDeducedMismatch;

case TemplateArgument::NullPtr:
  if (Arg.getKind() == TemplateArgument::NullPtr &&
      S.Context.hasSameType(Param.getNullPtrType(), Arg.getNullPtrType()))
    return Sema::TDK_Success;

  Info.FirstArg = Param;
  Info.SecondArg = Arg;
  return Sema::TDK_NonDeducedMismatch;

case TemplateArgument::Integral:
  if (Arg.getKind() == TemplateArgument::Integral) {
    if (hasSameExtendedValue(Param.getAsIntegral(), Arg.getAsIntegral()))
      return Sema::TDK_Success;

    Info.FirstArg = Param;
    Info.SecondArg = Arg;
    return Sema::TDK_NonDeducedMismatch;
  }

  if (Arg.getKind() == TemplateArgument::Expression) {
    Info.FirstArg = Param;
    Info.SecondArg = Arg;
    return Sema::TDK_NonDeducedMismatch;
  }

  Info.FirstArg = Param;
  Info.SecondArg = Arg;
  return Sema::TDK_NonDeducedMismatch;

case TemplateArgument::Expression:
  if (NonTypeTemplateParmDecl *NTTP
        = getDeducedParameterFromExpr(Info, Param.getAsExpr())) {
    if (Arg.getKind() == TemplateArgument::Integral)
      return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
                                           Arg.getAsIntegral(),
                                           Arg.getIntegralType(),
                                           /*ArrayBound=*/false,
                                           Info, Deduced);
    if (Arg.getKind() == TemplateArgument::NullPtr)
      return DeduceNullPtrTemplateArgument(S, TemplateParams, NTTP,
                                           Arg.getNullPtrType(),
                                           Info, Deduced);
    if (Arg.getKind() == TemplateArgument::Expression)
      return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
                                           Arg.getAsExpr(), Info, Deduced);
    if (Arg.getKind() == TemplateArgument::Declaration)
      return DeduceNonTypeTemplateArgument(S, TemplateParams, NTTP,
                                           Arg.getAsDecl(),
                                           Arg.getParamTypeForDecl(),
                                           Info, Deduced);

    Info.FirstArg = Param;
    Info.SecondArg = Arg;
    return Sema::TDK_NonDeducedMismatch;
  }

  // Can't deduce anything, but that's okay.
  return Sema::TDK_Success;

case TemplateArgument::Pack:
  llvm_unreachable("Argument packs should be expanded by the caller!")::llvm::llvm_unreachable_internal("Argument packs should be expanded by the caller!"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2224);
}

llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2227);
2228}

2230/// Determine whether there is a template argument to be used for
2231/// deduction.
2232///
2233/// This routine "expands" argument packs in-place, overriding its input
2234/// parameters so that \c Args[ArgIdx] will be the available template argument.
2235///
2236/// \returns true if there is another template argument (which will be at
2237/// \c Args[ArgIdx]), false otherwise.
2238static bool hasTemplateArgumentForDeduction(ArrayRef<TemplateArgument> &Args,
                                          unsigned &ArgIdx) {
if (ArgIdx == Args.size())
  return false;

const TemplateArgument &Arg = Args[ArgIdx];
if (Arg.getKind() != TemplateArgument::Pack)
  return true;

assert(ArgIdx == Args.size() - 1 && "Pack not at the end of argument list?")((ArgIdx == Args.size() - 1 && "Pack not at the end of argument list?"
) ? static_cast<void> (0) : __assert_fail ("ArgIdx == Args.size() - 1 && \"Pack not at the end of argument list?\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2247, __PRETTY_FUNCTION__));
Args = Arg.pack_elements();
ArgIdx = 0;
return ArgIdx < Args.size();
2251}

2253/// Determine whether the given set of template arguments has a pack
2254/// expansion that is not the last template argument.
2255static bool hasPackExpansionBeforeEnd(ArrayRef<TemplateArgument> Args) {
bool FoundPackExpansion = false;
for (const auto &A : Args) {
  if (FoundPackExpansion)
    return true;

  if (A.getKind() == TemplateArgument::Pack)
    return hasPackExpansionBeforeEnd(A.pack_elements());

  // FIXME: If this is a fixed-arity pack expansion from an outer level of
  // templates, it should not be treated as a pack expansion.
  if (A.isPackExpansion())
    FoundPackExpansion = true;
}

return false;
2271}

2273static Sema::TemplateDeductionResult
2274DeduceTemplateArguments(Sema &S, TemplateParameterList *TemplateParams,
                      ArrayRef<TemplateArgument> Params,
                      ArrayRef<TemplateArgument> Args,
                      TemplateDeductionInfo &Info,
                      SmallVectorImpl<DeducedTemplateArgument> &Deduced,
                      bool NumberOfArgumentsMustMatch) {
// C++0x [temp.deduct.type]p9:
//   If the template argument list of P contains a pack expansion that is not
//   the last template argument, the entire template argument list is a
//   non-deduced context.
if (hasPackExpansionBeforeEnd(Params))
  return Sema::TDK_Success;

// C++0x [temp.deduct.type]p9:
//   If P has a form that contains <T> or <i>, then each argument Pi of the
//   respective template argument list P is compared with the corresponding
//   argument Ai of the corresponding template argument list of A.
unsigned ArgIdx = 0, ParamIdx = 0;
for (; hasTemplateArgumentForDeduction(Params, ParamIdx); ++ParamIdx) {
  if (!Params[ParamIdx].isPackExpansion()) {
    // The simple case: deduce template arguments by matching Pi and Ai.

    // Check whether we have enough arguments.
    if (!hasTemplateArgumentForDeduction(Args, ArgIdx))
      return NumberOfArgumentsMustMatch
                 ? Sema::TDK_MiscellaneousDeductionFailure
                 : Sema::TDK_Success;

    // C++1z [temp.deduct.type]p9:
    //   During partial ordering, if Ai was originally a pack expansion [and]
    //   Pi is not a pack expansion, template argument deduction fails.
    if (Args[ArgIdx].isPackExpansion())
      return Sema::TDK_MiscellaneousDeductionFailure;

    // Perform deduction for this Pi/Ai pair.
    if (Sema::TemplateDeductionResult Result
          = DeduceTemplateArguments(S, TemplateParams,
                                    Params[ParamIdx], Args[ArgIdx],
                                    Info, Deduced))
      return Result;

    // Move to the next argument.
    ++ArgIdx;
    continue;
  }

  // The parameter is a pack expansion.

  // C++0x [temp.deduct.type]p9:
  //   If Pi is a pack expansion, then the pattern of Pi is compared with
  //   each remaining argument in the template argument list of A. Each
  //   comparison deduces template arguments for subsequent positions in the
  //   template parameter packs expanded by Pi.
  TemplateArgument Pattern = Params[ParamIdx].getPackExpansionPattern();

  // Prepare to deduce the packs within the pattern.
  PackDeductionScope PackScope(S, TemplateParams, Deduced, Info, Pattern);

  // Keep track of the deduced template arguments for each parameter pack
  // expanded by this pack expansion (the outer index) and for each
  // template argument (the inner SmallVectors).
  for (; hasTemplateArgumentForDeduction(Args, ArgIdx) &&
         PackScope.hasNextElement();
       ++ArgIdx) {
    // Deduce template arguments from the pattern.
    if (Sema::TemplateDeductionResult Result
          = DeduceTemplateArguments(S, TemplateParams, Pattern, Args[ArgIdx],
                                    Info, Deduced))
      return Result;

    PackScope.nextPackElement();
  }

  // Build argument packs for each of the parameter packs expanded by this
  // pack expansion.
  if (auto Result = PackScope.finish())
    return Result;
}

return Sema::TDK_Success;
2354}

2356static Sema::TemplateDeductionResult
2357DeduceTemplateArguments(Sema &S,
                      TemplateParameterList *TemplateParams,
                      const TemplateArgumentList &ParamList,
                      const TemplateArgumentList &ArgList,
                      TemplateDeductionInfo &Info,
                      SmallVectorImpl<DeducedTemplateArgument> &Deduced) {
return DeduceTemplateArguments(S, TemplateParams, ParamList.asArray(),
                               ArgList.asArray(), Info, Deduced,
                               /*NumberOfArgumentsMustMatch*/false);
2366}

2368/// Determine whether two template arguments are the same.
2369static bool isSameTemplateArg(ASTContext &Context,
                            TemplateArgument X,
                            const TemplateArgument &Y,
                            bool PackExpansionMatchesPack = false) {
// If we're checking deduced arguments (X) against original arguments (Y),
// we will have flattened packs to non-expansions in X.
if (PackExpansionMatchesPack && X.isPackExpansion() && !Y.isPackExpansion())
  X = X.getPackExpansionPattern();

if (X.getKind() != Y.getKind())
  return false;

switch (X.getKind()) {
  case TemplateArgument::Null:
    llvm_unreachable("Comparing NULL template argument")::llvm::llvm_unreachable_internal("Comparing NULL template argument"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2383);

  case TemplateArgument::Type:
    return Context.getCanonicalType(X.getAsType()) ==
           Context.getCanonicalType(Y.getAsType());

  case TemplateArgument::Declaration:
    return isSameDeclaration(X.getAsDecl(), Y.getAsDecl());

  case TemplateArgument::NullPtr:
    return Context.hasSameType(X.getNullPtrType(), Y.getNullPtrType());

  case TemplateArgument::Template:
  case TemplateArgument::TemplateExpansion:
    return Context.getCanonicalTemplateName(
                  X.getAsTemplateOrTemplatePattern()).getAsVoidPointer() ==
           Context.getCanonicalTemplateName(
                  Y.getAsTemplateOrTemplatePattern()).getAsVoidPointer();

  case TemplateArgument::Integral:
    return hasSameExtendedValue(X.getAsIntegral(), Y.getAsIntegral());

  case TemplateArgument::Expression: {
    llvm::FoldingSetNodeID XID, YID;
    X.getAsExpr()->Profile(XID, Context, true);
    Y.getAsExpr()->Profile(YID, Context, true);
    return XID == YID;
  }

  case TemplateArgument::Pack:
    if (X.pack_size() != Y.pack_size())
      return false;

    for (TemplateArgument::pack_iterator XP = X.pack_begin(),
                                      XPEnd = X.pack_end(),
                                         YP = Y.pack_begin();
         XP != XPEnd; ++XP, ++YP)
      if (!isSameTemplateArg(Context, *XP, *YP, PackExpansionMatchesPack))
        return false;

    return true;
}

llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2426);
2427}

2429/// Allocate a TemplateArgumentLoc where all locations have
2430/// been initialized to the given location.
2431///
2432/// \param Arg The template argument we are producing template argument
2433/// location information for.
2434///
2435/// \param NTTPType For a declaration template argument, the type of
2436/// the non-type template parameter that corresponds to this template
2437/// argument. Can be null if no type sugar is available to add to the
2438/// type from the template argument.
2439///
2440/// \param Loc The source location to use for the resulting template
2441/// argument.
2442TemplateArgumentLoc
2443Sema::getTrivialTemplateArgumentLoc(const TemplateArgument &Arg,
                                  QualType NTTPType, SourceLocation Loc) {
switch (Arg.getKind()) {
case TemplateArgument::Null:
  llvm_unreachable("Can't get a NULL template argument here")::llvm::llvm_unreachable_internal("Can't get a NULL template argument here"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2447);

case TemplateArgument::Type:
  return TemplateArgumentLoc(
      Arg, Context.getTrivialTypeSourceInfo(Arg.getAsType(), Loc));

case TemplateArgument::Declaration: {
  if (NTTPType.isNull())
    NTTPType = Arg.getParamTypeForDecl();
  Expr *E = BuildExpressionFromDeclTemplateArgument(Arg, NTTPType, Loc)
                .getAs<Expr>();
  return TemplateArgumentLoc(TemplateArgument(E), E);
}

case TemplateArgument::NullPtr: {
  if (NTTPType.isNull())
    NTTPType = Arg.getNullPtrType();
  Expr *E = BuildExpressionFromDeclTemplateArgument(Arg, NTTPType, Loc)
                .getAs<Expr>();
  return TemplateArgumentLoc(TemplateArgument(NTTPType, /*isNullPtr*/true),
                             E);
}

case TemplateArgument::Integral: {
  Expr *E =
      BuildExpressionFromIntegralTemplateArgument(Arg, Loc).getAs<Expr>();
  return TemplateArgumentLoc(TemplateArgument(E), E);
}

  case TemplateArgument::Template:
  case TemplateArgument::TemplateExpansion: {
    NestedNameSpecifierLocBuilder Builder;
    TemplateName Template = Arg.getAsTemplate();
    if (DependentTemplateName *DTN = Template.getAsDependentTemplateName())
      Builder.MakeTrivial(Context, DTN->getQualifier(), Loc);
    else if (QualifiedTemplateName *QTN =
                 Template.getAsQualifiedTemplateName())
      Builder.MakeTrivial(Context, QTN->getQualifier(), Loc);

    if (Arg.getKind() == TemplateArgument::Template)
      return TemplateArgumentLoc(Arg, Builder.getWithLocInContext(Context),
                                 Loc);

    return TemplateArgumentLoc(Arg, Builder.getWithLocInContext(Context),
                               Loc, Loc);
  }

case TemplateArgument::Expression:
  return TemplateArgumentLoc(Arg, Arg.getAsExpr());

case TemplateArgument::Pack:
  return TemplateArgumentLoc(Arg, TemplateArgumentLocInfo());
}

llvm_unreachable("Invalid TemplateArgument Kind!")::llvm::llvm_unreachable_internal("Invalid TemplateArgument Kind!"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2501);
2502}

2504/// Convert the given deduced template argument and add it to the set of
2505/// fully-converted template arguments.
2506static bool
2507ConvertDeducedTemplateArgument(Sema &S, NamedDecl *Param,
                             DeducedTemplateArgument Arg,
                             NamedDecl *Template,
                             TemplateDeductionInfo &Info,
                             bool IsDeduced,
                             SmallVectorImpl<TemplateArgument> &Output) {
auto ConvertArg = [&](DeducedTemplateArgument Arg,
                      unsigned ArgumentPackIndex) {
  // Convert the deduced template argument into a template
  // argument that we can check, almost as if the user had written
  // the template argument explicitly.
  TemplateArgumentLoc ArgLoc =
      S.getTrivialTemplateArgumentLoc(Arg, QualType(), Info.getLocation());

  // Check the template argument, converting it as necessary.
  return S.CheckTemplateArgument(
      Param, ArgLoc, Template, Template->getLocation(),
      Template->getSourceRange().getEnd(), ArgumentPackIndex, Output,
      IsDeduced
          ? (Arg.wasDeducedFromArrayBound() ? Sema::CTAK_DeducedFromArrayBound
                                            : Sema::CTAK_Deduced)
          : Sema::CTAK_Specified);
};

if (Arg.getKind() == TemplateArgument::Pack) {
  // This is a template argument pack, so check each of its arguments against
  // the template parameter.
  SmallVector<TemplateArgument, 2> PackedArgsBuilder;
  for (const auto &P : Arg.pack_elements()) {
    // When converting the deduced template argument, append it to the
    // general output list. We need to do this so that the template argument
    // checking logic has all of the prior template arguments available.
    DeducedTemplateArgument InnerArg(P);
    InnerArg.setDeducedFromArrayBound(Arg.wasDeducedFromArrayBound());
    assert(InnerArg.getKind() != TemplateArgument::Pack &&((InnerArg.getKind() != TemplateArgument::Pack && "deduced nested pack"
) ? static_cast<void> (0) : __assert_fail ("InnerArg.getKind() != TemplateArgument::Pack && \"deduced nested pack\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2542, __PRETTY_FUNCTION__))
           "deduced nested pack")((InnerArg.getKind() != TemplateArgument::Pack && "deduced nested pack"
) ? static_cast<void> (0) : __assert_fail ("InnerArg.getKind() != TemplateArgument::Pack && \"deduced nested pack\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2542, __PRETTY_FUNCTION__));
    if (P.isNull()) {
      // We deduced arguments for some elements of this pack, but not for
      // all of them. This happens if we get a conditionally-non-deduced
      // context in a pack expansion (such as an overload set in one of the
      // arguments).
      S.Diag(Param->getLocation(),
             diag::err_template_arg_deduced_incomplete_pack)
        << Arg << Param;
      return true;
    }
    if (ConvertArg(InnerArg, PackedArgsBuilder.size()))
      return true;

    // Move the converted template argument into our argument pack.
    PackedArgsBuilder.push_back(Output.pop_back_val());
  }

  // If the pack is empty, we still need to substitute into the parameter
  // itself, in case that substitution fails.
  if (PackedArgsBuilder.empty()) {
    LocalInstantiationScope Scope(S);
    TemplateArgumentList TemplateArgs(TemplateArgumentList::OnStack, Output);
    MultiLevelTemplateArgumentList Args(TemplateArgs);

    if (auto *NTTP = dyn_cast<NonTypeTemplateParmDecl>(Param)) {
      Sema::InstantiatingTemplate Inst(S, Template->getLocation(), Template,
                                       NTTP, Output,
                                       Template->getSourceRange());
      if (Inst.isInvalid() ||
          S.SubstType(NTTP->getType(), Args, NTTP->getLocation(),
                      NTTP->getDeclName()).isNull())
        return true;
    } else if (auto *TTP = dyn_cast<TemplateTemplateParmDecl>(Param)) {
      Sema::InstantiatingTemplate Inst(S, Template->getLocation(), Template,
                                       TTP, Output,
                                       Template->getSourceRange());
      if (Inst.isInvalid() || !S.SubstDecl(TTP, S.CurContext, Args))
        return true;
    }
    // For type parameters, no substitution is ever required.
  }

  // Create the resulting argument pack.
  Output.push_back(
      TemplateArgument::CreatePackCopy(S.Context, PackedArgsBuilder));
  return false;
}

return ConvertArg(Arg, 0);
2592}

2594// FIXME: This should not be a template, but
2595// ClassTemplatePartialSpecializationDecl sadly does not derive from
2596// TemplateDecl.
2597template<typename TemplateDeclT>
2598static Sema::TemplateDeductionResult ConvertDeducedTemplateArguments(
  Sema &S, TemplateDeclT *Template, bool IsDeduced,
  SmallVectorImpl<DeducedTemplateArgument> &Deduced,
  TemplateDeductionInfo &Info, SmallVectorImpl<TemplateArgument> &Builder,
  LocalInstantiationScope *CurrentInstantiationScope = nullptr,
  unsigned NumAlreadyConverted = 0, bool PartialOverloading = false) {
TemplateParameterList *TemplateParams = Template->getTemplateParameters();

for (unsigned I = 0, N = TemplateParams->size(); I != N; ++I) {
  NamedDecl *Param = TemplateParams->getParam(I);

  // C++0x [temp.arg.explicit]p3:
  //    A trailing template parameter pack (14.5.3) not otherwise deduced will
  //    be deduced to an empty sequence of template arguments.
  // FIXME: Where did the word "trailing" come from?
  if (Deduced[I].isNull() && Param->isTemplateParameterPack()) {
    if (auto Result = PackDeductionScope(S, TemplateParams, Deduced, Info, I)
                          .finish(/*TreatNoDeductionsAsNonDeduced*/false))
      return Result;
  }

  if (!Deduced[I].isNull()) {
    if (I < NumAlreadyConverted) {
      // We may have had explicitly-specified template arguments for a
      // template parameter pack (that may or may not have been extended
      // via additional deduced arguments).
      if (Param->isParameterPack() && CurrentInstantiationScope &&
          CurrentInstantiationScope->getPartiallySubstitutedPack() == Param) {
        // Forget the partially-substituted pack; its substitution is now
        // complete.
        CurrentInstantiationScope->ResetPartiallySubstitutedPack();
        // We still need to check the argument in case it was extended by
        // deduction.
      } else {
        // We have already fully type-checked and converted this
        // argument, because it was explicitly-specified. Just record the
        // presence of this argument.
        Builder.push_back(Deduced[I]);
        continue;
      }
    }

    // We may have deduced this argument, so it still needs to be
    // checked and converted.
    if (ConvertDeducedTemplateArgument(S, Param, Deduced[I], Template, Info,
                                       IsDeduced, Builder)) {
      Info.Param = makeTemplateParameter(Param);
      // FIXME: These template arguments are temporary. Free them!
      Info.reset(TemplateArgumentList::CreateCopy(S.Context, Builder));
      return Sema::TDK_SubstitutionFailure;
    }

    continue;
  }

  // Substitute into the default template argument, if available.
  bool HasDefaultArg = false;
  TemplateDecl *TD = dyn_cast<TemplateDecl>(Template);
  if (!TD) {
    assert(isa<ClassTemplatePartialSpecializationDecl>(Template) ||((isa<ClassTemplatePartialSpecializationDecl>(Template)
 || isa<VarTemplatePartialSpecializationDecl>(Template)
) ? static_cast<void> (0) : __assert_fail ("isa<ClassTemplatePartialSpecializationDecl>(Template) || isa<VarTemplatePartialSpecializationDecl>(Template)"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2658, __PRETTY_FUNCTION__))
           isa<VarTemplatePartialSpecializationDecl>(Template))((isa<ClassTemplatePartialSpecializationDecl>(Template)
 || isa<VarTemplatePartialSpecializationDecl>(Template)
) ? static_cast<void> (0) : __assert_fail ("isa<ClassTemplatePartialSpecializationDecl>(Template) || isa<VarTemplatePartialSpecializationDecl>(Template)"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 2658, __PRETTY_FUNCTION__));
    return Sema::TDK_Incomplete;
  }

  TemplateArgumentLoc DefArg = S.SubstDefaultTemplateArgumentIfAvailable(
      TD, TD->getLocation(), TD->getSourceRange().getEnd(), Param, Builder,
      HasDefaultArg);

  // If there was no default argument, deduction is incomplete.
  if (DefArg.getArgument().isNull()) {
    Info.Param = makeTemplateParameter(
        const_cast<NamedDecl *>(TemplateParams->getParam(I)));
    Info.reset(TemplateArgumentList::CreateCopy(S.Context, Builder));
    if (PartialOverloading) break;

    return HasDefaultArg ? Sema::TDK_SubstitutionFailure
                         : Sema::TDK_Incomplete;
  }

  // Check whether we can actually use the default argument.
  if (S.CheckTemplateArgument(Param, DefArg, TD, TD->getLocation(),
                              TD->getSourceRange().getEnd(), 0, Builder,
                              Sema::CTAK_Specified)) {
    Info.Param = makeTemplateParameter(
                       const_cast<NamedDecl *>(TemplateParams->getParam(I)));
    // FIXME: These template arguments are temporary. Free them!
    Info.reset(TemplateArgumentList::CreateCopy(S.Context, Builder));
    return Sema::TDK_SubstitutionFailure;
  }

  // If we get here, we successfully used the default template argument.
}

return Sema::TDK_Success;
2692}

2694static DeclContext *getAsDeclContextOrEnclosing(Decl *D) {
if (auto *DC = dyn_cast<DeclContext>(D))
  return DC;
return D->getDeclContext();
2698}

2700template<typename T> struct IsPartialSpecialization {
static constexpr bool value = false;
2702};
2703template<>
2704struct IsPartialSpecialization<ClassTemplatePartialSpecializationDecl> {
static constexpr bool value = true;
2706};
2707template<>
2708struct IsPartialSpecialization<VarTemplatePartialSpecializationDecl> {
static constexpr bool value = true;
2710};

2712/// Complete template argument deduction for a partial specialization.
2713template <typename T>
2714static typename std::enable_if<IsPartialSpecialization<T>::value,
                             Sema::TemplateDeductionResult>::type
2716FinishTemplateArgumentDeduction(
  Sema &S, T *Partial, bool IsPartialOrdering,
  const TemplateArgumentList &TemplateArgs,
  SmallVectorImpl<DeducedTemplateArgument> &Deduced,
  TemplateDeductionInfo &Info) {
// Unevaluated SFINAE context.
EnterExpressionEvaluationContext Unevaluated(
    S, Sema::ExpressionEvaluationContext::Unevaluated);
Sema::SFINAETrap Trap(S);

Sema::ContextRAII SavedContext(S, getAsDeclContextOrEnclosing(Partial));

// C++ [temp.deduct.type]p2:
//   [...] or if any template argument remains neither deduced nor
//   explicitly specified, template argument deduction fails.
SmallVector<TemplateArgument, 4> Builder;
if (auto Result = ConvertDeducedTemplateArguments(
        S, Partial, IsPartialOrdering, Deduced, Info, Builder))
  return Result;

// Form the template argument list from the deduced template arguments.
TemplateArgumentList *DeducedArgumentList
  = TemplateArgumentList::CreateCopy(S.Context, Builder);

Info.reset(DeducedArgumentList);

// Substitute the deduced template arguments into the template
// arguments of the class template partial specialization, and
// verify that the instantiated template arguments are both valid
// and are equivalent to the template arguments originally provided
// to the class template.
LocalInstantiationScope InstScope(S);
auto *Template = Partial->getSpecializedTemplate();
const ASTTemplateArgumentListInfo *PartialTemplArgInfo =
    Partial->getTemplateArgsAsWritten();
const TemplateArgumentLoc *PartialTemplateArgs =
    PartialTemplArgInfo->getTemplateArgs();

TemplateArgumentListInfo InstArgs(PartialTemplArgInfo->LAngleLoc,
                                  PartialTemplArgInfo->RAngleLoc);

if (S.Subst(PartialTemplateArgs, PartialTemplArgInfo->NumTemplateArgs,
            InstArgs, MultiLevelTemplateArgumentList(*DeducedArgumentList))) {
  unsigned ArgIdx = InstArgs.size(), ParamIdx = ArgIdx;
  if (ParamIdx >= Partial->getTemplateParameters()->size())
    ParamIdx = Partial->getTemplateParameters()->size() - 1;

  Decl *Param = const_cast<NamedDecl *>(
      Partial->getTemplateParameters()->getParam(ParamIdx));
  Info.Param = makeTemplateParameter(Param);
  Info.FirstArg = PartialTemplateArgs[ArgIdx].getArgument();
  return Sema::TDK_SubstitutionFailure;
}

SmallVector<TemplateArgument, 4> ConvertedInstArgs;
if (S.CheckTemplateArgumentList(Template, Partial->getLocation(), InstArgs,
                                false, ConvertedInstArgs))
  return Sema::TDK_SubstitutionFailure;

TemplateParameterList *TemplateParams = Template->getTemplateParameters();
for (unsigned I = 0, E = TemplateParams->size(); I != E; ++I) {
  TemplateArgument InstArg = ConvertedInstArgs.data()[I];
  if (!isSameTemplateArg(S.Context, TemplateArgs[I], InstArg)) {
    Info.Param = makeTemplateParameter(TemplateParams->getParam(I));
    Info.FirstArg = TemplateArgs[I];
    Info.SecondArg = InstArg;
    return Sema::TDK_NonDeducedMismatch;
  }
}

if (Trap.hasErrorOccurred())
  return Sema::TDK_SubstitutionFailure;

return Sema::TDK_Success;
2790}

2792/// Complete template argument deduction for a class or variable template,
2793/// when partial ordering against a partial specialization.
2794// FIXME: Factor out duplication with partial specialization version above.
2795static Sema::TemplateDeductionResult FinishTemplateArgumentDeduction(
  Sema &S, TemplateDecl *Template, bool PartialOrdering,
  const TemplateArgumentList &TemplateArgs,
  SmallVectorImpl<DeducedTemplateArgument> &Deduced,
  TemplateDeductionInfo &Info) {
// Unevaluated SFINAE context.
EnterExpressionEvaluationContext Unevaluated(
    S, Sema::ExpressionEvaluationContext::Unevaluated);
Sema::SFINAETrap Trap(S);

Sema::ContextRAII SavedContext(S, getAsDeclContextOrEnclosing(Template));

// C++ [temp.deduct.type]p2:
//   [...] or if any template argument remains neither deduced nor
//   explicitly specified, template argument deduction fails.
SmallVector<TemplateArgument, 4> Builder;
if (auto Result = ConvertDeducedTemplateArguments(
        S, Template, /*IsDeduced*/PartialOrdering, Deduced, Info, Builder))
  return Result;

// Check that we produced the correct argument list.
TemplateParameterList *TemplateParams = Template->getTemplateParameters();
for (unsigned I = 0, E = TemplateParams->size(); I != E; ++I) {
  TemplateArgument InstArg = Builder[I];
  if (!isSameTemplateArg(S.Context, TemplateArgs[I], InstArg,
                         /*PackExpansionMatchesPack*/true)) {
    Info.Param = makeTemplateParameter(TemplateParams->getParam(I));
    Info.FirstArg = TemplateArgs[I];
    Info.SecondArg = InstArg;
    return Sema::TDK_NonDeducedMismatch;
  }
}

if (Trap.hasErrorOccurred())
  return Sema::TDK_SubstitutionFailure;

return Sema::TDK_Success;
2832}


2835/// Perform template argument deduction to determine whether
2836/// the given template arguments match the given class template
2837/// partial specialization per C++ [temp.class.spec.match].
2838Sema::TemplateDeductionResult
2839Sema::DeduceTemplateArguments(ClassTemplatePartialSpecializationDecl *Partial,
                            const TemplateArgumentList &TemplateArgs,
                            TemplateDeductionInfo &Info) {
if (Partial->isInvalidDecl())
  return TDK_Invalid;

// C++ [temp.class.spec.match]p2:
//   A partial specialization matches a given actual template
//   argument list if the template arguments of the partial
//   specialization can be deduced from the actual template argument
//   list (14.8.2).

// Unevaluated SFINAE context.
EnterExpressionEvaluationContext Unevaluated(
    *this, Sema::ExpressionEvaluationContext::Unevaluated);
SFINAETrap Trap(*this);

SmallVector<DeducedTemplateArgument, 4> Deduced;
Deduced.resize(Partial->getTemplateParameters()->size());
if (TemplateDeductionResult Result
      = ::DeduceTemplateArguments(*this,
                                  Partial->getTemplateParameters(),
                                  Partial->getTemplateArgs(),
                                  TemplateArgs, Info, Deduced))
  return Result;

SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end());
InstantiatingTemplate Inst(*this, Info.getLocation(), Partial, DeducedArgs,
                           Info);
if (Inst.isInvalid())
  return TDK_InstantiationDepth;

if (Trap.hasErrorOccurred())
  return Sema::TDK_SubstitutionFailure;

return ::FinishTemplateArgumentDeduction(
    *this, Partial, /*IsPartialOrdering=*/false, TemplateArgs, Deduced, Info);
2876}

2878/// Perform template argument deduction to determine whether
2879/// the given template arguments match the given variable template
2880/// partial specialization per C++ [temp.class.spec.match].
2881Sema::TemplateDeductionResult
2882Sema::DeduceTemplateArguments(VarTemplatePartialSpecializationDecl *Partial,
                            const TemplateArgumentList &TemplateArgs,
                            TemplateDeductionInfo &Info) {
if (Partial->isInvalidDecl())
  return TDK_Invalid;

// C++ [temp.class.spec.match]p2:
//   A partial specialization matches a given actual template
//   argument list if the template arguments of the partial
//   specialization can be deduced from the actual template argument
//   list (14.8.2).

// Unevaluated SFINAE context.
EnterExpressionEvaluationContext Unevaluated(
    *this, Sema::ExpressionEvaluationContext::Unevaluated);
SFINAETrap Trap(*this);

SmallVector<DeducedTemplateArgument, 4> Deduced;
Deduced.resize(Partial->getTemplateParameters()->size());
if (TemplateDeductionResult Result = ::DeduceTemplateArguments(
        *this, Partial->getTemplateParameters(), Partial->getTemplateArgs(),
        TemplateArgs, Info, Deduced))
  return Result;

SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end());
InstantiatingTemplate Inst(*this, Info.getLocation(), Partial, DeducedArgs,
                           Info);
if (Inst.isInvalid())
  return TDK_InstantiationDepth;

if (Trap.hasErrorOccurred())
  return Sema::TDK_SubstitutionFailure;

return ::FinishTemplateArgumentDeduction(
    *this, Partial, /*IsPartialOrdering=*/false, TemplateArgs, Deduced, Info);
2917}

2919/// Determine whether the given type T is a simple-template-id type.
2920static bool isSimpleTemplateIdType(QualType T) {
if (const TemplateSpecializationType *Spec36.1
'Spec' is non-null
1
'Spec' is non-null

36.1	'Spec' is non-null

←

Taking true branch

→

2922 = T->getAs<TemplateSpecializationType>())

←

Assuming the object is a 'TemplateSpecializationType'

→

2923 return Spec->getTemplateName().getAsTemplateDecl() != nullptr;

←

Assuming the condition is false

→

←

Returning zero, which participates in a condition later

→

2924 2925 // C++17 [temp.local]p2: 2926 // the injected-class-name [...] is equivalent to the template-name followed 2927 // by the template-arguments of the class template specialization or partial 2928 // specialization enclosed in <> 2929 // ... which means it's equivalent to a simple-template-id. 2930 // 2931 // This only arises during class template argument deduction for a copy 2932 // deduction candidate, where it permits slicing. 2933 if (T->getAs<InjectedClassNameType>()) 2934 return true; 2935 2936 return false; 2937} 2938 2939/// Substitute the explicitly-provided template arguments into the 2940/// given function template according to C++ [temp.arg.explicit]. 2941/// 2942/// \param FunctionTemplate the function template into which the explicit 2943/// template arguments will be substituted. 2944/// 2945/// \param ExplicitTemplateArgs the explicitly-specified template 2946/// arguments. 2947/// 2948/// \param Deduced the deduced template arguments, which will be populated 2949/// with the converted and checked explicit template arguments. 2950/// 2951/// \param ParamTypes will be populated with the instantiated function 2952/// parameters. 2953/// 2954/// \param FunctionType if non-NULL, the result type of the function template 2955/// will also be instantiated and the pointed-to value will be updated with 2956/// the instantiated function type. 2957/// 2958/// \param Info if substitution fails for any reason, this object will be 2959/// populated with more information about the failure. 2960/// 2961/// \returns TDK_Success if substitution was successful, or some failure 2962/// condition. 2963Sema::TemplateDeductionResult 2964Sema::SubstituteExplicitTemplateArguments( 2965 FunctionTemplateDecl *FunctionTemplate, 2966 TemplateArgumentListInfo &ExplicitTemplateArgs, 2967 SmallVectorImpl<DeducedTemplateArgument> &Deduced, 2968 SmallVectorImpl<QualType> &ParamTypes, 2969 QualType *FunctionType, 2970 TemplateDeductionInfo &Info) { 2971 FunctionDecl *Function = FunctionTemplate->getTemplatedDecl(); 2972 TemplateParameterList *TemplateParams 2973 = FunctionTemplate->getTemplateParameters(); 2974 2975 if (ExplicitTemplateArgs.size() == 0) { 2976 // No arguments to substitute; just copy over the parameter types and 2977 // fill in the function type. 2978 for (auto P : Function->parameters()) 2979 ParamTypes.push_back(P->getType()); 2980 2981 if (FunctionType) 2982 *FunctionType = Function->getType(); 2983 return TDK_Success; 2984 } 2985 2986 // Unevaluated SFINAE context. 2987 EnterExpressionEvaluationContext Unevaluated( 2988 *this, Sema::ExpressionEvaluationContext::Unevaluated); 2989 SFINAETrap Trap(*this); 2990 2991 // C++ [temp.arg.explicit]p3: 2992 // Template arguments that are present shall be specified in the 2993 // declaration order of their corresponding template-parameters. The 2994 // template argument list shall not specify more template-arguments than 2995 // there are corresponding template-parameters. 2996 SmallVector<TemplateArgument, 4> Builder; 2997 2998 // Enter a new template instantiation context where we check the 2999 // explicitly-specified template arguments against this function template, 3000 // and then substitute them into the function parameter types. 3001 SmallVector<TemplateArgument, 4> DeducedArgs; 3002 InstantiatingTemplate Inst( 3003 *this, Info.getLocation(), FunctionTemplate, DeducedArgs, 3004 CodeSynthesisContext::ExplicitTemplateArgumentSubstitution, Info); 3005 if (Inst.isInvalid()) 3006 return TDK_InstantiationDepth; 3007 3008 if (CheckTemplateArgumentList(FunctionTemplate, SourceLocation(), 3009 ExplicitTemplateArgs, true, Builder, false) || 3010 Trap.hasErrorOccurred()) { 3011 unsigned Index = Builder.size(); 3012 if (Index >= TemplateParams->size()) 3013 return TDK_SubstitutionFailure; 3014 Info.Param = makeTemplateParameter(TemplateParams->getParam(Index)); 3015 return TDK_InvalidExplicitArguments; 3016 } 3017 3018 // Form the template argument list from the explicitly-specified 3019 // template arguments. 3020 TemplateArgumentList *ExplicitArgumentList 3021 = TemplateArgumentList::CreateCopy(Context, Builder); 3022 Info.setExplicitArgs(ExplicitArgumentList); 3023 3024 // Template argument deduction and the final substitution should be 3025 // done in the context of the templated declaration. Explicit 3026 // argument substitution, on the other hand, needs to happen in the 3027 // calling context. 3028 ContextRAII SavedContext(*this, FunctionTemplate->getTemplatedDecl()); 3029 3030 // If we deduced template arguments for a template parameter pack, 3031 // note that the template argument pack is partially substituted and record 3032 // the explicit template arguments. They'll be used as part of deduction 3033 // for this template parameter pack. 3034 unsigned PartiallySubstitutedPackIndex = -1u; 3035 if (!Builder.empty()) { 3036 const TemplateArgument &Arg = Builder.back(); 3037 if (Arg.getKind() == TemplateArgument::Pack) { 3038 auto *Param = TemplateParams->getParam(Builder.size() - 1); 3039 // If this is a fully-saturated fixed-size pack, it should be 3040 // fully-substituted, not partially-substituted. 3041 Optional<unsigned> Expansions = getExpandedPackSize(Param); 3042 if (!Expansions || Arg.pack_size() < *Expansions) { 3043 PartiallySubstitutedPackIndex = Builder.size() - 1; 3044 CurrentInstantiationScope->SetPartiallySubstitutedPack( 3045 Param, Arg.pack_begin(), Arg.pack_size()); 3046 } 3047 } 3048 } 3049 3050 const FunctionProtoType *Proto 3051 = Function->getType()->getAs<FunctionProtoType>(); 3052 assert(Proto && "Function template does not have a prototype?")((Proto && "Function template does not have a prototype?"
) ? static_cast<void> (0) : __assert_fail ("Proto && \"Function template does not have a prototype?\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 3052, __PRETTY_FUNCTION__)); 3053 3054 // Isolate our substituted parameters from our caller. 3055 LocalInstantiationScope InstScope(*this, /*MergeWithOuterScope*/true); 3056 3057 ExtParameterInfoBuilder ExtParamInfos; 3058 3059 // Instantiate the types of each of the function parameters given the 3060 // explicitly-specified template arguments. If the function has a trailing 3061 // return type, substitute it after the arguments to ensure we substitute 3062 // in lexical order. 3063 if (Proto->hasTrailingReturn()) { 3064 if (SubstParmTypes(Function->getLocation(), Function->parameters(), 3065 Proto->getExtParameterInfosOrNull(), 3066 MultiLevelTemplateArgumentList(*ExplicitArgumentList), 3067 ParamTypes, /*params*/ nullptr, ExtParamInfos)) 3068 return TDK_SubstitutionFailure; 3069 } 3070 3071 // Instantiate the return type. 3072 QualType ResultType; 3073 { 3074 // C++11 [expr.prim.general]p3: 3075 // If a declaration declares a member function or member function 3076 // template of a class X, the expression this is a prvalue of type 3077 // "pointer to cv-qualifier-seq X" between the optional cv-qualifer-seq 3078 // and the end of the function-definition, member-declarator, or 3079 // declarator. 3080 Qualifiers ThisTypeQuals; 3081 CXXRecordDecl *ThisContext = nullptr; 3082 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Function)) { 3083 ThisContext = Method->getParent(); 3084 ThisTypeQuals = Method->getMethodQualifiers(); 3085 } 3086 3087 CXXThisScopeRAII ThisScope(*this, ThisContext, ThisTypeQuals, 3088 getLangOpts().CPlusPlus11); 3089 3090 ResultType = 3091 SubstType(Proto->getReturnType(), 3092 MultiLevelTemplateArgumentList(*ExplicitArgumentList), 3093 Function->getTypeSpecStartLoc(), Function->getDeclName()); 3094 if (ResultType.isNull() || Trap.hasErrorOccurred()) 3095 return TDK_SubstitutionFailure; 3096 // CUDA: Kernel function must have 'void' return type. 3097 if (getLangOpts().CUDA) 3098 if (Function->hasAttr<CUDAGlobalAttr>() && !ResultType->isVoidType()) { 3099 Diag(Function->getLocation(), diag::err_kern_type_not_void_return) 3100 << Function->getType() << Function->getSourceRange(); 3101 return TDK_SubstitutionFailure; 3102 } 3103 } 3104 3105 // Instantiate the types of each of the function parameters given the 3106 // explicitly-specified template arguments if we didn't do so earlier. 3107 if (!Proto->hasTrailingReturn() && 3108 SubstParmTypes(Function->getLocation(), Function->parameters(), 3109 Proto->getExtParameterInfosOrNull(), 3110 MultiLevelTemplateArgumentList(*ExplicitArgumentList), 3111 ParamTypes, /*params*/ nullptr, ExtParamInfos)) 3112 return TDK_SubstitutionFailure; 3113 3114 if (FunctionType) { 3115 auto EPI = Proto->getExtProtoInfo(); 3116 EPI.ExtParameterInfos = ExtParamInfos.getPointerOrNull(ParamTypes.size()); 3117 3118 // In C++1z onwards, exception specifications are part of the function type, 3119 // so substitution into the type must also substitute into the exception 3120 // specification. 3121 SmallVector<QualType, 4> ExceptionStorage; 3122 if (getLangOpts().CPlusPlus17 && 3123 SubstExceptionSpec( 3124 Function->getLocation(), EPI.ExceptionSpec, ExceptionStorage, 3125 MultiLevelTemplateArgumentList(*ExplicitArgumentList))) 3126 return TDK_SubstitutionFailure; 3127 3128 *FunctionType = BuildFunctionType(ResultType, ParamTypes, 3129 Function->getLocation(), 3130 Function->getDeclName(), 3131 EPI); 3132 if (FunctionType->isNull() || Trap.hasErrorOccurred()) 3133 return TDK_SubstitutionFailure; 3134 } 3135 3136 // C++ [temp.arg.explicit]p2: 3137 // Trailing template arguments that can be deduced (14.8.2) may be 3138 // omitted from the list of explicit template-arguments. If all of the 3139 // template arguments can be deduced, they may all be omitted; in this 3140 // case, the empty template argument list <> itself may also be omitted. 3141 // 3142 // Take all of the explicitly-specified arguments and put them into 3143 // the set of deduced template arguments. The partially-substituted 3144 // parameter pack, however, will be set to NULL since the deduction 3145 // mechanism handles the partially-substituted argument pack directly. 3146 Deduced.reserve(TemplateParams->size()); 3147 for (unsigned I = 0, N = ExplicitArgumentList->size(); I != N; ++I) { 3148 const TemplateArgument &Arg = ExplicitArgumentList->get(I); 3149 if (I == PartiallySubstitutedPackIndex) 3150 Deduced.push_back(DeducedTemplateArgument()); 3151 else 3152 Deduced.push_back(Arg); 3153 } 3154 3155 return TDK_Success; 3156} 3157 3158/// Check whether the deduced argument type for a call to a function 3159/// template matches the actual argument type per C++ [temp.deduct.call]p4. 3160static Sema::TemplateDeductionResult 3161CheckOriginalCallArgDeduction(Sema &S, TemplateDeductionInfo &Info, 3162 Sema::OriginalCallArg OriginalArg, 3163 QualType DeducedA) { 3164 ASTContext &Context = S.Context; 3165 3166 auto Failed = [&]() -> Sema::TemplateDeductionResult { 3167 Info.FirstArg = TemplateArgument(DeducedA); 3168 Info.SecondArg = TemplateArgument(OriginalArg.OriginalArgType); 3169 Info.CallArgIndex = OriginalArg.ArgIdx; 3170 return OriginalArg.DecomposedParam ? Sema::TDK_DeducedMismatchNested 3171 : Sema::TDK_DeducedMismatch; 3172 }; 3173 3174 QualType A = OriginalArg.OriginalArgType; 3175 QualType OriginalParamType = OriginalArg.OriginalParamType; 3176 3177 // Check for type equality (top-level cv-qualifiers are ignored). 3178 if (Context.hasSameUnqualifiedType(A, DeducedA)) 3179 return Sema::TDK_Success; 3180 3181 // Strip off references on the argument types; they aren't needed for 3182 // the following checks. 3183 if (const ReferenceType *DeducedARef = DeducedA->getAs<ReferenceType>()) 3184 DeducedA = DeducedARef->getPointeeType(); 3185 if (const ReferenceType *ARef = A->getAs<ReferenceType>()) 3186 A = ARef->getPointeeType(); 3187 3188 // C++ [temp.deduct.call]p4: 3189 // [...] However, there are three cases that allow a difference: 3190 // - If the original P is a reference type, the deduced A (i.e., the 3191 // type referred to by the reference) can be more cv-qualified than 3192 // the transformed A. 3193 if (const ReferenceType *OriginalParamRef 3194 = OriginalParamType->getAs<ReferenceType>()) { 3195 // We don't want to keep the reference around any more. 3196 OriginalParamType = OriginalParamRef->getPointeeType(); 3197 3198 // FIXME: Resolve core issue (no number yet): if the original P is a 3199 // reference type and the transformed A is function type "noexcept F", 3200 // the deduced A can be F. 3201 QualType Tmp; 3202 if (A->isFunctionType() && S.IsFunctionConversion(A, DeducedA, Tmp)) 3203 return Sema::TDK_Success; 3204 3205 Qualifiers AQuals = A.getQualifiers(); 3206 Qualifiers DeducedAQuals = DeducedA.getQualifiers(); 3207 3208 // Under Objective-C++ ARC, the deduced type may have implicitly 3209 // been given strong or (when dealing with a const reference) 3210 // unsafe_unretained lifetime. If so, update the original 3211 // qualifiers to include this lifetime. 3212 if (S.getLangOpts().ObjCAutoRefCount && 3213 ((DeducedAQuals.getObjCLifetime() == Qualifiers::OCL_Strong && 3214 AQuals.getObjCLifetime() == Qualifiers::OCL_None) || 3215 (DeducedAQuals.hasConst() && 3216 DeducedAQuals.getObjCLifetime() == Qualifiers::OCL_ExplicitNone))) { 3217 AQuals.setObjCLifetime(DeducedAQuals.getObjCLifetime()); 3218 } 3219 3220 if (AQuals == DeducedAQuals) { 3221 // Qualifiers match; there's nothing to do. 3222 } else if (!DeducedAQuals.compatiblyIncludes(AQuals)) { 3223 return Failed(); 3224 } else { 3225 // Qualifiers are compatible, so have the argument type adopt the 3226 // deduced argument type's qualifiers as if we had performed the 3227 // qualification conversion. 3228 A = Context.getQualifiedType(A.getUnqualifiedType(), DeducedAQuals); 3229 } 3230 } 3231 3232 // - The transformed A can be another pointer or pointer to member 3233 // type that can be converted to the deduced A via a function pointer 3234 // conversion and/or a qualification conversion. 3235 // 3236 // Also allow conversions which merely strip __attribute__((noreturn)) from 3237 // function types (recursively). 3238 bool ObjCLifetimeConversion = false; 3239 QualType ResultTy; 3240 if ((A->isAnyPointerType() || A->isMemberPointerType()) && 3241 (S.IsQualificationConversion(A, DeducedA, false, 3242 ObjCLifetimeConversion) || 3243 S.IsFunctionConversion(A, DeducedA, ResultTy))) 3244 return Sema::TDK_Success; 3245 3246 // - If P is a class and P has the form simple-template-id, then the 3247 // transformed A can be a derived class of the deduced A. [...] 3248 // [...] Likewise, if P is a pointer to a class of the form 3249 // simple-template-id, the transformed A can be a pointer to a 3250 // derived class pointed to by the deduced A. 3251 if (const PointerType *OriginalParamPtr 3252 = OriginalParamType->getAs<PointerType>()) { 3253 if (const PointerType *DeducedAPtr = DeducedA->getAs<PointerType>()) { 3254 if (const PointerType *APtr = A->getAs<PointerType>()) { 3255 if (A->getPointeeType()->isRecordType()) { 3256 OriginalParamType = OriginalParamPtr->getPointeeType(); 3257 DeducedA = DeducedAPtr->getPointeeType(); 3258 A = APtr->getPointeeType(); 3259 } 3260 } 3261 } 3262 } 3263 3264 if (Context.hasSameUnqualifiedType(A, DeducedA)) 3265 return Sema::TDK_Success; 3266 3267 if (A->isRecordType() && isSimpleTemplateIdType(OriginalParamType) && 3268 S.IsDerivedFrom(Info.getLocation(), A, DeducedA)) 3269 return Sema::TDK_Success; 3270 3271 return Failed(); 3272} 3273 3274/// Find the pack index for a particular parameter index in an instantiation of 3275/// a function template with specific arguments. 3276/// 3277/// \return The pack index for whichever pack produced this parameter, or -1 3278/// if this was not produced by a parameter. Intended to be used as the 3279/// ArgumentPackSubstitutionIndex for further substitutions. 3280// FIXME: We should track this in OriginalCallArgs so we don't need to 3281// reconstruct it here. 3282static unsigned getPackIndexForParam(Sema &S, 3283 FunctionTemplateDecl *FunctionTemplate, 3284 const MultiLevelTemplateArgumentList &Args, 3285 unsigned ParamIdx) { 3286 unsigned Idx = 0; 3287 for (auto *PD : FunctionTemplate->getTemplatedDecl()->parameters()) { 3288 if (PD->isParameterPack()) { 3289 unsigned NumExpansions = 3290 S.getNumArgumentsInExpansion(PD->getType(), Args).getValueOr(1); 3291 if (Idx + NumExpansions > ParamIdx) 3292 return ParamIdx - Idx; 3293 Idx += NumExpansions; 3294 } else { 3295 if (Idx == ParamIdx) 3296 return -1; // Not a pack expansion 3297 ++Idx; 3298 } 3299 } 3300 3301 llvm_unreachable("parameter index would not be produced from template")::llvm::llvm_unreachable_internal("parameter index would not be produced from template"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 3301); 3302} 3303 3304/// Finish template argument deduction for a function template, 3305/// checking the deduced template arguments for completeness and forming 3306/// the function template specialization. 3307/// 3308/// \param OriginalCallArgs If non-NULL, the original call arguments against 3309/// which the deduced argument types should be compared. 3310Sema::TemplateDeductionResult Sema::FinishTemplateArgumentDeduction( 3311 FunctionTemplateDecl *FunctionTemplate, 3312 SmallVectorImpl<DeducedTemplateArgument> &Deduced, 3313 unsigned NumExplicitlySpecified, FunctionDecl *&Specialization, 3314 TemplateDeductionInfo &Info, 3315 SmallVectorImpl<OriginalCallArg> const *OriginalCallArgs, 3316 bool PartialOverloading, llvm::function_ref<bool()> CheckNonDependent) { 3317 // Unevaluated SFINAE context. 3318 EnterExpressionEvaluationContext Unevaluated( 3319 *this, Sema::ExpressionEvaluationContext::Unevaluated); 3320 SFINAETrap Trap(*this); 3321 3322 // Enter a new template instantiation context while we instantiate the 3323 // actual function declaration. 3324 SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), Deduced.end()); 3325 InstantiatingTemplate Inst( 3326 *this, Info.getLocation(), FunctionTemplate, DeducedArgs, 3327 CodeSynthesisContext::DeducedTemplateArgumentSubstitution, Info); 3328 if (Inst.isInvalid()) 3329 return TDK_InstantiationDepth; 3330 3331 ContextRAII SavedContext(*this, FunctionTemplate->getTemplatedDecl()); 3332 3333 // C++ [temp.deduct.type]p2: 3334 // [...] or if any template argument remains neither deduced nor 3335 // explicitly specified, template argument deduction fails. 3336 SmallVector<TemplateArgument, 4> Builder; 3337 if (auto Result = ConvertDeducedTemplateArguments( 3338 *this, FunctionTemplate, /*IsDeduced*/true, Deduced, Info, Builder, 3339 CurrentInstantiationScope, NumExplicitlySpecified, 3340 PartialOverloading)) 3341 return Result; 3342 3343 // C++ [temp.deduct.call]p10: [DR1391] 3344 // If deduction succeeds for all parameters that contain 3345 // template-parameters that participate in template argument deduction, 3346 // and all template arguments are explicitly specified, deduced, or 3347 // obtained from default template arguments, remaining parameters are then 3348 // compared with the corresponding arguments. For each remaining parameter 3349 // P with a type that was non-dependent before substitution of any 3350 // explicitly-specified template arguments, if the corresponding argument 3351 // A cannot be implicitly converted to P, deduction fails. 3352 if (CheckNonDependent()) 3353 return TDK_NonDependentConversionFailure; 3354 3355 // Form the template argument list from the deduced template arguments. 3356 TemplateArgumentList *DeducedArgumentList 3357 = TemplateArgumentList::CreateCopy(Context, Builder); 3358 Info.reset(DeducedArgumentList); 3359 3360 // Substitute the deduced template arguments into the function template 3361 // declaration to produce the function template specialization. 3362 DeclContext *Owner = FunctionTemplate->getDeclContext(); 3363 if (FunctionTemplate->getFriendObjectKind()) 3364 Owner = FunctionTemplate->getLexicalDeclContext(); 3365 MultiLevelTemplateArgumentList SubstArgs(*DeducedArgumentList); 3366 Specialization = cast_or_null<FunctionDecl>( 3367 SubstDecl(FunctionTemplate->getTemplatedDecl(), Owner, SubstArgs)); 3368 if (!Specialization || Specialization->isInvalidDecl()) 3369 return TDK_SubstitutionFailure; 3370 3371 assert(Specialization->getPrimaryTemplate()->getCanonicalDecl() ==((Specialization->getPrimaryTemplate()->getCanonicalDecl
() == FunctionTemplate->getCanonicalDecl()) ? static_cast<
void> (0) : __assert_fail ("Specialization->getPrimaryTemplate()->getCanonicalDecl() == FunctionTemplate->getCanonicalDecl()"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 3372, __PRETTY_FUNCTION__)) 3372 FunctionTemplate->getCanonicalDecl())((Specialization->getPrimaryTemplate()->getCanonicalDecl
() == FunctionTemplate->getCanonicalDecl()) ? static_cast<
void> (0) : __assert_fail ("Specialization->getPrimaryTemplate()->getCanonicalDecl() == FunctionTemplate->getCanonicalDecl()"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 3372, __PRETTY_FUNCTION__)); 3373 3374 // If the template argument list is owned by the function template 3375 // specialization, release it. 3376 if (Specialization->getTemplateSpecializationArgs() == DeducedArgumentList && 3377 !Trap.hasErrorOccurred()) 3378 Info.take(); 3379 3380 // There may have been an error that did not prevent us from constructing a 3381 // declaration. Mark the declaration invalid and return with a substitution 3382 // failure. 3383 if (Trap.hasErrorOccurred()) { 3384 Specialization->setInvalidDecl(true); 3385 return TDK_SubstitutionFailure; 3386 } 3387 3388 if (OriginalCallArgs) { 3389 // C++ [temp.deduct.call]p4: 3390 // In general, the deduction process attempts to find template argument 3391 // values that will make the deduced A identical to A (after the type A 3392 // is transformed as described above). [...] 3393 llvm::SmallDenseMap<std::pair<unsigned, QualType>, QualType> DeducedATypes; 3394 for (unsigned I = 0, N = OriginalCallArgs->size(); I != N; ++I) { 3395 OriginalCallArg OriginalArg = (*OriginalCallArgs)[I]; 3396 3397 auto ParamIdx = OriginalArg.ArgIdx; 3398 if (ParamIdx >= Specialization->getNumParams()) 3399 // FIXME: This presumably means a pack ended up smaller than we 3400 // expected while deducing. Should this not result in deduction 3401 // failure? Can it even happen? 3402 continue; 3403 3404 QualType DeducedA; 3405 if (!OriginalArg.DecomposedParam) { 3406 // P is one of the function parameters, just look up its substituted 3407 // type. 3408 DeducedA = Specialization->getParamDecl(ParamIdx)->getType(); 3409 } else { 3410 // P is a decomposed element of a parameter corresponding to a 3411 // braced-init-list argument. Substitute back into P to find the 3412 // deduced A. 3413 QualType &CacheEntry = 3414 DeducedATypes[{ParamIdx, OriginalArg.OriginalParamType}]; 3415 if (CacheEntry.isNull()) { 3416 ArgumentPackSubstitutionIndexRAII PackIndex( 3417 *this, getPackIndexForParam(*this, FunctionTemplate, SubstArgs, 3418 ParamIdx)); 3419 CacheEntry = 3420 SubstType(OriginalArg.OriginalParamType, SubstArgs, 3421 Specialization->getTypeSpecStartLoc(), 3422 Specialization->getDeclName()); 3423 } 3424 DeducedA = CacheEntry; 3425 } 3426 3427 if (auto TDK = 3428 CheckOriginalCallArgDeduction(*this, Info, OriginalArg, DeducedA)) 3429 return TDK; 3430 } 3431 } 3432 3433 // If we suppressed any diagnostics while performing template argument 3434 // deduction, and if we haven't already instantiated this declaration, 3435 // keep track of these diagnostics. They'll be emitted if this specialization 3436 // is actually used. 3437 if (Info.diag_begin() != Info.diag_end()) { 3438 SuppressedDiagnosticsMap::iterator 3439 Pos = SuppressedDiagnostics.find(Specialization->getCanonicalDecl()); 3440 if (Pos == SuppressedDiagnostics.end()) 3441 SuppressedDiagnostics[Specialization->getCanonicalDecl()] 3442 .append(Info.diag_begin(), Info.diag_end()); 3443 } 3444 3445 return TDK_Success; 3446} 3447 3448/// Gets the type of a function for template-argument-deducton 3449/// purposes when it's considered as part of an overload set. 3450static QualType GetTypeOfFunction(Sema &S, const OverloadExpr::FindResult &R, 3451 FunctionDecl *Fn) { 3452 // We may need to deduce the return type of the function now. 3453 if (S.getLangOpts().CPlusPlus14 && Fn->getReturnType()->isUndeducedType() && 3454 S.DeduceReturnType(Fn, R.Expression->getExprLoc(), /*Diagnose*/ false)) 3455 return {}; 3456 3457 if (CXXMethodDecl *Method = dyn_cast<CXXMethodDecl>(Fn)) 3458 if (Method->isInstance()) { 3459 // An instance method that's referenced in a form that doesn't 3460 // look like a member pointer is just invalid. 3461 if (!R.HasFormOfMemberPointer) 3462 return {}; 3463 3464 return S.Context.getMemberPointerType(Fn->getType(), 3465 S.Context.getTypeDeclType(Method->getParent()).getTypePtr()); 3466 } 3467 3468 if (!R.IsAddressOfOperand) return Fn->getType(); 3469 return S.Context.getPointerType(Fn->getType()); 3470} 3471 3472/// Apply the deduction rules for overload sets. 3473/// 3474/// \return the null type if this argument should be treated as an 3475/// undeduced context 3476static QualType 3477ResolveOverloadForDeduction(Sema &S, TemplateParameterList *TemplateParams, 3478 Expr *Arg, QualType ParamType, 3479 bool ParamWasReference) { 3480 3481 OverloadExpr::FindResult R = OverloadExpr::find(Arg); 3482 3483 OverloadExpr *Ovl = R.Expression; 3484 3485 // C++0x [temp.deduct.call]p4 3486 unsigned TDF = 0; 3487 if (ParamWasReference) 3488 TDF |= TDF_ParamWithReferenceType; 3489 if (R.IsAddressOfOperand) 3490 TDF |= TDF_IgnoreQualifiers; 3491 3492 // C++0x [temp.deduct.call]p6: 3493 // When P is a function type, pointer to function type, or pointer 3494 // to member function type: 3495 3496 if (!ParamType->isFunctionType() && 3497 !ParamType->isFunctionPointerType() && 3498 !ParamType->isMemberFunctionPointerType()) { 3499 if (Ovl->hasExplicitTemplateArgs()) { 3500 // But we can still look for an explicit specialization. 3501 if (FunctionDecl *ExplicitSpec 3502 = S.ResolveSingleFunctionTemplateSpecialization(Ovl)) 3503 return GetTypeOfFunction(S, R, ExplicitSpec); 3504 } 3505 3506 DeclAccessPair DAP; 3507 if (FunctionDecl *Viable = 3508 S.resolveAddressOfOnlyViableOverloadCandidate(Arg, DAP)) 3509 return GetTypeOfFunction(S, R, Viable); 3510 3511 return {}; 3512 } 3513 3514 // Gather the explicit template arguments, if any. 3515 TemplateArgumentListInfo ExplicitTemplateArgs; 3516 if (Ovl->hasExplicitTemplateArgs()) 3517 Ovl->copyTemplateArgumentsInto(ExplicitTemplateArgs); 3518 QualType Match; 3519 for (UnresolvedSetIterator I = Ovl->decls_begin(), 3520 E = Ovl->decls_end(); I != E; ++I) { 3521 NamedDecl *D = (*I)->getUnderlyingDecl(); 3522 3523 if (FunctionTemplateDecl *FunTmpl = dyn_cast<FunctionTemplateDecl>(D)) { 3524 // - If the argument is an overload set containing one or more 3525 // function templates, the parameter is treated as a 3526 // non-deduced context. 3527 if (!Ovl->hasExplicitTemplateArgs()) 3528 return {}; 3529 3530 // Otherwise, see if we can resolve a function type 3531 FunctionDecl *Specialization = nullptr; 3532 TemplateDeductionInfo Info(Ovl->getNameLoc()); 3533 if (S.DeduceTemplateArguments(FunTmpl, &ExplicitTemplateArgs, 3534 Specialization, Info)) 3535 continue; 3536 3537 D = Specialization; 3538 } 3539 3540 FunctionDecl *Fn = cast<FunctionDecl>(D); 3541 QualType ArgType = GetTypeOfFunction(S, R, Fn); 3542 if (ArgType.isNull()) continue; 3543 3544 // Function-to-pointer conversion. 3545 if (!ParamWasReference && ParamType->isPointerType() && 3546 ArgType->isFunctionType()) 3547 ArgType = S.Context.getPointerType(ArgType); 3548 3549 // - If the argument is an overload set (not containing function 3550 // templates), trial argument deduction is attempted using each 3551 // of the members of the set. If deduction succeeds for only one 3552 // of the overload set members, that member is used as the 3553 // argument value for the deduction. If deduction succeeds for 3554 // more than one member of the overload set the parameter is 3555 // treated as a non-deduced context. 3556 3557 // We do all of this in a fresh context per C++0x [temp.deduct.type]p2: 3558 // Type deduction is done independently for each P/A pair, and 3559 // the deduced template argument values are then combined. 3560 // So we do not reject deductions which were made elsewhere. 3561 SmallVector<DeducedTemplateArgument, 8> 3562 Deduced(TemplateParams->size()); 3563 TemplateDeductionInfo Info(Ovl->getNameLoc()); 3564 Sema::TemplateDeductionResult Result 3565 = DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, ParamType, 3566 ArgType, Info, Deduced, TDF); 3567 if (Result) continue; 3568 if (!Match.isNull()) 3569 return {}; 3570 Match = ArgType; 3571 } 3572 3573 return Match; 3574} 3575 3576/// Perform the adjustments to the parameter and argument types 3577/// described in C++ [temp.deduct.call]. 3578/// 3579/// \returns true if the caller should not attempt to perform any template 3580/// argument deduction based on this P/A pair because the argument is an 3581/// overloaded function set that could not be resolved. 3582static bool AdjustFunctionParmAndArgTypesForDeduction( 3583 Sema &S, TemplateParameterList *TemplateParams, unsigned FirstInnerIndex, 3584 QualType &ParamType, QualType &ArgType, Expr *Arg, unsigned &TDF) { 3585 // C++0x [temp.deduct.call]p3: 3586 // If P is a cv-qualified type, the top level cv-qualifiers of P's type 3587 // are ignored for type deduction. 3588 if (ParamType.hasQualifiers())

←

Assuming the condition is false

→

←

Taking false branch

→

3589 ParamType = ParamType.getUnqualifiedType(); 3590 3591 // [...] If P is a reference type, the type referred to by P is 3592 // used for type deduction. 3593 const ReferenceType *ParamRefType = ParamType->getAs<ReferenceType>();

←

Assuming the object is not a 'ReferenceType'

→

3594 if (ParamRefType

20.1	'ParamRefType' is null

20.1	'ParamRefType' is null

20.1	'ParamRefType' is null

)

←

Taking false branch

→

3595 ParamType = ParamRefType->getPointeeType(); 3596 3597 // Overload sets usually make this parameter an undeduced context, 3598 // but there are sometimes special circumstances. Typically 3599 // involving a template-id-expr. 3600 if (ArgType == S.Context.OverloadTy) {

←

Calling 'operator=='

→

←

Returning from 'operator=='

→

←

Taking false branch

→

3601 ArgType = ResolveOverloadForDeduction(S, TemplateParams, 3602 Arg, ParamType, 3603 ParamRefType != nullptr); 3604 if (ArgType.isNull()) 3605 return true; 3606 } 3607 3608 if (ParamRefType

29.1	'ParamRefType' is null

29.1	'ParamRefType' is null

29.1	'ParamRefType' is null

) {

←

Taking false branch

→

3609 // If the argument has incomplete array type, try to complete its type. 3610 if (ArgType->isIncompleteArrayType()) { 3611 S.completeExprArrayBound(Arg); 3612 ArgType = Arg->getType(); 3613 } 3614 3615 // C++1z [temp.deduct.call]p3: 3616 // If P is a forwarding reference and the argument is an lvalue, the type 3617 // "lvalue reference to A" is used in place of A for type deduction. 3618 if (isForwardingReference(QualType(ParamRefType, 0), FirstInnerIndex) && 3619 Arg->isLValue()) 3620 ArgType = S.Context.getLValueReferenceType(ArgType); 3621 } else { 3622 // C++ [temp.deduct.call]p2: 3623 // If P is not a reference type: 3624 // - If A is an array type, the pointer type produced by the 3625 // array-to-pointer standard conversion (4.2) is used in place of 3626 // A for type deduction; otherwise, 3627 if (ArgType->isArrayType())

←

Taking false branch

→

3628 ArgType = S.Context.getArrayDecayedType(ArgType); 3629 // - If A is a function type, the pointer type produced by the 3630 // function-to-pointer standard conversion (4.3) is used in place 3631 // of A for type deduction; otherwise, 3632 else if (ArgType->isFunctionType())

←

Taking true branch

→

3633 ArgType = S.Context.getPointerType(ArgType); 3634 else { 3635 // - If A is a cv-qualified type, the top level cv-qualifiers of A's 3636 // type are ignored for type deduction. 3637 ArgType = ArgType.getUnqualifiedType(); 3638 } 3639 } 3640 3641 // C++0x [temp.deduct.call]p4: 3642 // In general, the deduction process attempts to find template argument 3643 // values that will make the deduced A identical to A (after the type A 3644 // is transformed as described above). [...] 3645 TDF = TDF_SkipNonDependent; 3646 3647 // - If the original P is a reference type, the deduced A (i.e., the 3648 // type referred to by the reference) can be more cv-qualified than 3649 // the transformed A. 3650 if (ParamRefType

32.1	'ParamRefType' is null

32.1	'ParamRefType' is null

32.1	'ParamRefType' is null

)

←

Taking false branch

→

3651 TDF |= TDF_ParamWithReferenceType; 3652 // - The transformed A can be another pointer or pointer to member 3653 // type that can be converted to the deduced A via a qualification 3654 // conversion (4.4). 3655 if (ArgType->isPointerType() || ArgType->isMemberPointerType() ||

←

Taking false branch

→

3656 ArgType->isObjCObjectPointerType()) 3657 TDF |= TDF_IgnoreQualifiers; 3658 // - If P is a class and P has the form simple-template-id, then the 3659 // transformed A can be a derived class of the deduced A. Likewise, 3660 // if P is a pointer to a class of the form simple-template-id, the 3661 // transformed A can be a pointer to a derived class pointed to by 3662 // the deduced A. 3663 if (isSimpleTemplateIdType(ParamType) ||

←

Calling 'isSimpleTemplateIdType'

→

←

Returning from 'isSimpleTemplateIdType'

→

3664 (isa<PointerType>(ParamType) &&

←

Assuming 'ParamType' is a 'PointerType'

→

3665 isSimpleTemplateIdType( 3666 ParamType->getAs<PointerType>()->getPointeeType())))

←

Assuming the object is not a 'PointerType'

→

←

Called C++ object pointer is null

3667 TDF |= TDF_DerivedClass; 3668 3669 return false; 3670} 3671 3672static bool 3673hasDeducibleTemplateParameters(Sema &S, FunctionTemplateDecl *FunctionTemplate, 3674 QualType T); 3675 3676static Sema::TemplateDeductionResult DeduceTemplateArgumentsFromCallArgument( 3677 Sema &S, TemplateParameterList *TemplateParams, unsigned FirstInnerIndex, 3678 QualType ParamType, Expr *Arg, TemplateDeductionInfo &Info, 3679 SmallVectorImpl<DeducedTemplateArgument> &Deduced, 3680 SmallVectorImpl<Sema::OriginalCallArg> &OriginalCallArgs, 3681 bool DecomposedParam, unsigned ArgIdx, unsigned TDF); 3682 3683/// Attempt template argument deduction from an initializer list 3684/// deemed to be an argument in a function call. 3685static Sema::TemplateDeductionResult DeduceFromInitializerList( 3686 Sema &S, TemplateParameterList *TemplateParams, QualType AdjustedParamType, 3687 InitListExpr *ILE, TemplateDeductionInfo &Info, 3688 SmallVectorImpl<DeducedTemplateArgument> &Deduced, 3689 SmallVectorImpl<Sema::OriginalCallArg> &OriginalCallArgs, unsigned ArgIdx, 3690 unsigned TDF) { 3691 // C++ [temp.deduct.call]p1: (CWG 1591) 3692 // If removing references and cv-qualifiers from P gives 3693 // std::initializer_list<P0> or P0[N] for some P0 and N and the argument is 3694 // a non-empty initializer list, then deduction is performed instead for 3695 // each element of the initializer list, taking P0 as a function template 3696 // parameter type and the initializer element as its argument 3697 // 3698 // We've already removed references and cv-qualifiers here. 3699 if (!ILE->getNumInits()) 3700 return Sema::TDK_Success; 3701 3702 QualType ElTy; 3703 auto *ArrTy = S.Context.getAsArrayType(AdjustedParamType); 3704 if (ArrTy) 3705 ElTy = ArrTy->getElementType(); 3706 else if (!S.isStdInitializerList(AdjustedParamType, &ElTy)) { 3707 // Otherwise, an initializer list argument causes the parameter to be 3708 // considered a non-deduced context 3709 return Sema::TDK_Success; 3710 } 3711 3712 // Resolving a core issue: a braced-init-list containing any designators is 3713 // a non-deduced context. 3714 for (Expr *E : ILE->inits()) 3715 if (isa<DesignatedInitExpr>(E)) 3716 return Sema::TDK_Success; 3717 3718 // Deduction only needs to be done for dependent types. 3719 if (ElTy->isDependentType()) { 3720 for (Expr *E : ILE->inits()) { 3721 if (auto Result = DeduceTemplateArgumentsFromCallArgument( 3722 S, TemplateParams, 0, ElTy, E, Info, Deduced, OriginalCallArgs, true, 3723 ArgIdx, TDF)) 3724 return Result; 3725 } 3726 } 3727 3728 // in the P0[N] case, if N is a non-type template parameter, N is deduced 3729 // from the length of the initializer list. 3730 if (auto *DependentArrTy = dyn_cast_or_null<DependentSizedArrayType>(ArrTy)) { 3731 // Determine the array bound is something we can deduce. 3732 if (NonTypeTemplateParmDecl *NTTP = 3733 getDeducedParameterFromExpr(Info, DependentArrTy->getSizeExpr())) { 3734 // We can perform template argument deduction for the given non-type 3735 // template parameter. 3736 // C++ [temp.deduct.type]p13: 3737 // The type of N in the type T[N] is std::size_t. 3738 QualType T = S.Context.getSizeType(); 3739 llvm::APInt Size(S.Context.getIntWidth(T), ILE->getNumInits()); 3740 if (auto Result = DeduceNonTypeTemplateArgument( 3741 S, TemplateParams, NTTP, llvm::APSInt(Size), T, 3742 /*ArrayBound=*/true, Info, Deduced)) 3743 return Result; 3744 } 3745 } 3746 3747 return Sema::TDK_Success; 3748} 3749 3750/// Perform template argument deduction per [temp.deduct.call] for a 3751/// single parameter / argument pair. 3752static Sema::TemplateDeductionResult DeduceTemplateArgumentsFromCallArgument( 3753 Sema &S, TemplateParameterList *TemplateParams, unsigned FirstInnerIndex, 3754 QualType ParamType, Expr *Arg, TemplateDeductionInfo &Info, 3755 SmallVectorImpl<DeducedTemplateArgument> &Deduced, 3756 SmallVectorImpl<Sema::OriginalCallArg> &OriginalCallArgs, 3757 bool DecomposedParam, unsigned ArgIdx, unsigned TDF) { 3758 QualType ArgType = Arg->getType(); 3759 QualType OrigParamType = ParamType; 3760 3761 // If P is a reference type [...] 3762 // If P is a cv-qualified type [...] 3763 if (AdjustFunctionParmAndArgTypesForDeduction(

←

Calling 'AdjustFunctionParmAndArgTypesForDeduction'

→

3764 S, TemplateParams, FirstInnerIndex, ParamType, ArgType, Arg, TDF)) 3765 return Sema::TDK_Success; 3766 3767 // If [...] the argument is a non-empty initializer list [...] 3768 if (InitListExpr *ILE = dyn_cast<InitListExpr>(Arg)) 3769 return DeduceFromInitializerList(S, TemplateParams, ParamType, ILE, Info, 3770 Deduced, OriginalCallArgs, ArgIdx, TDF); 3771 3772 // [...] the deduction process attempts to find template argument values 3773 // that will make the deduced A identical to A 3774 // 3775 // Keep track of the argument type and corresponding parameter index, 3776 // so we can check for compatibility between the deduced A and A. 3777 OriginalCallArgs.push_back( 3778 Sema::OriginalCallArg(OrigParamType, DecomposedParam, ArgIdx, ArgType)); 3779 return DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, ParamType, 3780 ArgType, Info, Deduced, TDF); 3781} 3782 3783/// Perform template argument deduction from a function call 3784/// (C++ [temp.deduct.call]). 3785/// 3786/// \param FunctionTemplate the function template for which we are performing 3787/// template argument deduction. 3788/// 3789/// \param ExplicitTemplateArgs the explicit template arguments provided 3790/// for this call. 3791/// 3792/// \param Args the function call arguments 3793/// 3794/// \param Specialization if template argument deduction was successful, 3795/// this will be set to the function template specialization produced by 3796/// template argument deduction. 3797/// 3798/// \param Info the argument will be updated to provide additional information 3799/// about template argument deduction. 3800/// 3801/// \param CheckNonDependent A callback to invoke to check conversions for 3802/// non-dependent parameters, between deduction and substitution, per DR1391. 3803/// If this returns true, substitution will be skipped and we return 3804/// TDK_NonDependentConversionFailure. The callback is passed the parameter 3805/// types (after substituting explicit template arguments). 3806/// 3807/// \returns the result of template argument deduction. 3808Sema::TemplateDeductionResult Sema::DeduceTemplateArguments( 3809 FunctionTemplateDecl *FunctionTemplate, 3810 TemplateArgumentListInfo *ExplicitTemplateArgs, ArrayRef<Expr *> Args, 3811 FunctionDecl *&Specialization, TemplateDeductionInfo &Info, 3812 bool PartialOverloading, 3813 llvm::function_ref<bool(ArrayRef<QualType>)> CheckNonDependent) { 3814 if (FunctionTemplate->isInvalidDecl())

Assuming the condition is false

→

←

Taking false branch

→

3815 return TDK_Invalid; 3816 3817 FunctionDecl *Function = FunctionTemplate->getTemplatedDecl(); 3818 unsigned NumParams = Function->getNumParams(); 3819 3820 unsigned FirstInnerIndex = getFirstInnerIndex(FunctionTemplate); 3821 3822 // C++ [temp.deduct.call]p1: 3823 // Template argument deduction is done by comparing each function template 3824 // parameter type (call it P) with the type of the corresponding argument 3825 // of the call (call it A) as described below. 3826 if (Args.size() < Function->getMinRequiredArguments() && !PartialOverloading)

←

Assuming the condition is false

→

3827 return TDK_TooFewArguments; 3828 else if (TooManyArguments(NumParams, Args.size(), PartialOverloading)) {

←

Taking false branch

→

3829 const FunctionProtoType *Proto 3830 = Function->getType()->getAs<FunctionProtoType>(); 3831 if (Proto->isTemplateVariadic()) 3832 /* Do nothing */; 3833 else if (!Proto->isVariadic()) 3834 return TDK_TooManyArguments; 3835 } 3836 3837 // The types of the parameters from which we will perform template argument 3838 // deduction. 3839 LocalInstantiationScope InstScope(*this); 3840 TemplateParameterList *TemplateParams 3841 = FunctionTemplate->getTemplateParameters(); 3842 SmallVector<DeducedTemplateArgument, 4> Deduced; 3843 SmallVector<QualType, 8> ParamTypes; 3844 unsigned NumExplicitlySpecified = 0; 3845 if (ExplicitTemplateArgs) {

←

Assuming 'ExplicitTemplateArgs' is null

→

←

Taking false branch

→

3846 TemplateDeductionResult Result = 3847 SubstituteExplicitTemplateArguments(FunctionTemplate, 3848 *ExplicitTemplateArgs, 3849 Deduced, 3850 ParamTypes, 3851 nullptr, 3852 Info); 3853 if (Result) 3854 return Result; 3855 3856 NumExplicitlySpecified = Deduced.size(); 3857 } else { 3858 // Just fill in the parameter types from the function declaration. 3859 for (unsigned I = 0; I != NumParams; ++I)

←

Assuming 'I' is equal to 'NumParams'

→

←

Loop condition is false. Execution continues on line 3863

→

3860 ParamTypes.push_back(Function->getParamDecl(I)->getType()); 3861 } 3862 3863 SmallVector<OriginalCallArg, 8> OriginalCallArgs; 3864 3865 // Deduce an argument of type ParamType from an expression with index ArgIdx. 3866 auto DeduceCallArgument = [&](QualType ParamType, unsigned ArgIdx) { 3867 // C++ [demp.deduct.call]p1: (DR1391) 3868 // Template argument deduction is done by comparing each function template 3869 // parameter that contains template-parameters that participate in 3870 // template argument deduction ... 3871 if (!hasDeducibleTemplateParameters(*this, FunctionTemplate, ParamType))

←

Taking false branch

→

3872 return Sema::TDK_Success; 3873 3874 // ... with the type of the corresponding argument 3875 return DeduceTemplateArgumentsFromCallArgument(

←

Calling 'DeduceTemplateArgumentsFromCallArgument'

→

3876 *this, TemplateParams, FirstInnerIndex, ParamType, Args[ArgIdx], Info, Deduced, 3877 OriginalCallArgs, /*Decomposed*/false, ArgIdx, /*TDF*/ 0); 3878 }; 3879 3880 // Deduce template arguments from the function parameters. 3881 Deduced.resize(TemplateParams->size()); 3882 SmallVector<QualType, 8> ParamTypesForArgChecking; 3883 for (unsigned ParamIdx = 0, NumParamTypes = ParamTypes.size(), ArgIdx = 0;

←

Loop condition is true. Entering loop body

→

3884 ParamIdx != NumParamTypes; ++ParamIdx) {

←

Assuming 'ParamIdx' is not equal to 'NumParamTypes'

→

3885 QualType ParamType = ParamTypes[ParamIdx]; 3886 3887 const PackExpansionType *ParamExpansion = 3888 dyn_cast<PackExpansionType>(ParamType); 3889 if (!ParamExpansion

10.1	'ParamExpansion' is null

10.1	'ParamExpansion' is null

10.1	'ParamExpansion' is null

) {

←

Taking true branch

→

3890 // Simple case: matching a function parameter to a function argument. 3891 if (ArgIdx >= Args.size())

←

Assuming the condition is false

→

←

Taking false branch

→

3892 break; 3893 3894 ParamTypesForArgChecking.push_back(ParamType); 3895 if (auto Result = DeduceCallArgument(ParamType, ArgIdx++))

←

Calling 'operator()'

→

3896 return Result; 3897 3898 continue; 3899 } 3900 3901 QualType ParamPattern = ParamExpansion->getPattern(); 3902 PackDeductionScope PackScope(*this, TemplateParams, Deduced, Info, 3903 ParamPattern); 3904 3905 // C++0x [temp.deduct.call]p1: 3906 // For a function parameter pack that occurs at the end of the 3907 // parameter-declaration-list, the type A of each remaining argument of 3908 // the call is compared with the type P of the declarator-id of the 3909 // function parameter pack. Each comparison deduces template arguments 3910 // for subsequent positions in the template parameter packs expanded by 3911 // the function parameter pack. When a function parameter pack appears 3912 // in a non-deduced context [not at the end of the list], the type of 3913 // that parameter pack is never deduced. 3914 // 3915 // FIXME: The above rule allows the size of the parameter pack to change 3916 // after we skip it (in the non-deduced case). That makes no sense, so 3917 // we instead notionally deduce the pack against N arguments, where N is 3918 // the length of the explicitly-specified pack if it's expanded by the 3919 // parameter pack and 0 otherwise, and we treat each deduction as a 3920 // non-deduced context. 3921 if (ParamIdx + 1 == NumParamTypes || PackScope.hasFixedArity()) { 3922 for (; ArgIdx < Args.size() && PackScope.hasNextElement(); 3923 PackScope.nextPackElement(), ++ArgIdx) { 3924 ParamTypesForArgChecking.push_back(ParamPattern); 3925 if (auto Result = DeduceCallArgument(ParamPattern, ArgIdx)) 3926 return Result; 3927 } 3928 } else { 3929 // If the parameter type contains an explicitly-specified pack that we 3930 // could not expand, skip the number of parameters notionally created 3931 // by the expansion. 3932 Optional<unsigned> NumExpansions = ParamExpansion->getNumExpansions(); 3933 if (NumExpansions && !PackScope.isPartiallyExpanded()) { 3934 for (unsigned I = 0; I != *NumExpansions && ArgIdx < Args.size(); 3935 ++I, ++ArgIdx) { 3936 ParamTypesForArgChecking.push_back(ParamPattern); 3937 // FIXME: Should we add OriginalCallArgs for these? What if the 3938 // corresponding argument is a list? 3939 PackScope.nextPackElement(); 3940 } 3941 } 3942 } 3943 3944 // Build argument packs for each of the parameter packs expanded by this 3945 // pack expansion. 3946 if (auto Result = PackScope.finish()) 3947 return Result; 3948 } 3949 3950 // Capture the context in which the function call is made. This is the context 3951 // that is needed when the accessibility of template arguments is checked. 3952 DeclContext *CallingCtx = CurContext; 3953 3954 return FinishTemplateArgumentDeduction( 3955 FunctionTemplate, Deduced, NumExplicitlySpecified, Specialization, Info, 3956 &OriginalCallArgs, PartialOverloading, [&, CallingCtx]() { 3957 ContextRAII SavedContext(*this, CallingCtx); 3958 return CheckNonDependent(ParamTypesForArgChecking); 3959 }); 3960} 3961 3962QualType Sema::adjustCCAndNoReturn(QualType ArgFunctionType, 3963 QualType FunctionType, 3964 bool AdjustExceptionSpec) { 3965 if (ArgFunctionType.isNull()) 3966 return ArgFunctionType; 3967 3968 const FunctionProtoType *FunctionTypeP = 3969 FunctionType->castAs<FunctionProtoType>(); 3970 const FunctionProtoType *ArgFunctionTypeP = 3971 ArgFunctionType->getAs<FunctionProtoType>(); 3972 3973 FunctionProtoType::ExtProtoInfo EPI = ArgFunctionTypeP->getExtProtoInfo(); 3974 bool Rebuild = false; 3975 3976 CallingConv CC = FunctionTypeP->getCallConv(); 3977 if (EPI.ExtInfo.getCC() != CC) { 3978 EPI.ExtInfo = EPI.ExtInfo.withCallingConv(CC); 3979 Rebuild = true; 3980 } 3981 3982 bool NoReturn = FunctionTypeP->getNoReturnAttr(); 3983 if (EPI.ExtInfo.getNoReturn() != NoReturn) { 3984 EPI.ExtInfo = EPI.ExtInfo.withNoReturn(NoReturn); 3985 Rebuild = true; 3986 } 3987 3988 if (AdjustExceptionSpec && (FunctionTypeP->hasExceptionSpec() || 3989 ArgFunctionTypeP->hasExceptionSpec())) { 3990 EPI.ExceptionSpec = FunctionTypeP->getExtProtoInfo().ExceptionSpec; 3991 Rebuild = true; 3992 } 3993 3994 if (!Rebuild) 3995 return ArgFunctionType; 3996 3997 return Context.getFunctionType(ArgFunctionTypeP->getReturnType(), 3998 ArgFunctionTypeP->getParamTypes(), EPI); 3999} 4000 4001/// Deduce template arguments when taking the address of a function 4002/// template (C++ [temp.deduct.funcaddr]) or matching a specialization to 4003/// a template. 4004/// 4005/// \param FunctionTemplate the function template for which we are performing 4006/// template argument deduction. 4007/// 4008/// \param ExplicitTemplateArgs the explicitly-specified template 4009/// arguments. 4010/// 4011/// \param ArgFunctionType the function type that will be used as the 4012/// "argument" type (A) when performing template argument deduction from the 4013/// function template's function type. This type may be NULL, if there is no 4014/// argument type to compare against, in C++0x [temp.arg.explicit]p3. 4015/// 4016/// \param Specialization if template argument deduction was successful, 4017/// this will be set to the function template specialization produced by 4018/// template argument deduction. 4019/// 4020/// \param Info the argument will be updated to provide additional information 4021/// about template argument deduction. 4022/// 4023/// \param IsAddressOfFunction If \c true, we are deducing as part of taking 4024/// the address of a function template per [temp.deduct.funcaddr] and 4025/// [over.over]. If \c false, we are looking up a function template 4026/// specialization based on its signature, per [temp.deduct.decl]. 4027/// 4028/// \returns the result of template argument deduction. 4029Sema::TemplateDeductionResult Sema::DeduceTemplateArguments( 4030 FunctionTemplateDecl *FunctionTemplate, 4031 TemplateArgumentListInfo *ExplicitTemplateArgs, QualType ArgFunctionType, 4032 FunctionDecl *&Specialization, TemplateDeductionInfo &Info, 4033 bool IsAddressOfFunction) { 4034 if (FunctionTemplate->isInvalidDecl()) 4035 return TDK_Invalid; 4036 4037 FunctionDecl *Function = FunctionTemplate->getTemplatedDecl(); 4038 TemplateParameterList *TemplateParams 4039 = FunctionTemplate->getTemplateParameters(); 4040 QualType FunctionType = Function->getType(); 4041 4042 // Substitute any explicit template arguments. 4043 LocalInstantiationScope InstScope(*this); 4044 SmallVector<DeducedTemplateArgument, 4> Deduced; 4045 unsigned NumExplicitlySpecified = 0; 4046 SmallVector<QualType, 4> ParamTypes; 4047 if (ExplicitTemplateArgs) { 4048 if (TemplateDeductionResult Result 4049 = SubstituteExplicitTemplateArguments(FunctionTemplate, 4050 *ExplicitTemplateArgs, 4051 Deduced, ParamTypes, 4052 &FunctionType, Info)) 4053 return Result; 4054 4055 NumExplicitlySpecified = Deduced.size(); 4056 } 4057 4058 // When taking the address of a function, we require convertibility of 4059 // the resulting function type. Otherwise, we allow arbitrary mismatches 4060 // of calling convention and noreturn. 4061 if (!IsAddressOfFunction) 4062 ArgFunctionType = adjustCCAndNoReturn(ArgFunctionType, FunctionType, 4063 /*AdjustExceptionSpec*/false); 4064 4065 // Unevaluated SFINAE context. 4066 EnterExpressionEvaluationContext Unevaluated( 4067 *this, Sema::ExpressionEvaluationContext::Unevaluated); 4068 SFINAETrap Trap(*this); 4069 4070 Deduced.resize(TemplateParams->size()); 4071 4072 // If the function has a deduced return type, substitute it for a dependent 4073 // type so that we treat it as a non-deduced context in what follows. If we 4074 // are looking up by signature, the signature type should also have a deduced 4075 // return type, which we instead expect to exactly match. 4076 bool HasDeducedReturnType = false; 4077 if (getLangOpts().CPlusPlus14 && IsAddressOfFunction && 4078 Function->getReturnType()->getContainedAutoType()) { 4079 FunctionType = SubstAutoType(FunctionType, Context.DependentTy); 4080 HasDeducedReturnType = true; 4081 } 4082 4083 if (!ArgFunctionType.isNull()) { 4084 unsigned TDF = 4085 TDF_TopLevelParameterTypeList | TDF_AllowCompatibleFunctionType; 4086 // Deduce template arguments from the function type. 4087 if (TemplateDeductionResult Result 4088 = DeduceTemplateArgumentsByTypeMatch(*this, TemplateParams, 4089 FunctionType, ArgFunctionType, 4090 Info, Deduced, TDF)) 4091 return Result; 4092 } 4093 4094 if (TemplateDeductionResult Result 4095 = FinishTemplateArgumentDeduction(FunctionTemplate, Deduced, 4096 NumExplicitlySpecified, 4097 Specialization, Info)) 4098 return Result; 4099 4100 // If the function has a deduced return type, deduce it now, so we can check 4101 // that the deduced function type matches the requested type. 4102 if (HasDeducedReturnType && 4103 Specialization->getReturnType()->isUndeducedType() && 4104 DeduceReturnType(Specialization, Info.getLocation(), false)) 4105 return TDK_MiscellaneousDeductionFailure; 4106 4107 // If the function has a dependent exception specification, resolve it now, 4108 // so we can check that the exception specification matches. 4109 auto *SpecializationFPT = 4110 Specialization->getType()->castAs<FunctionProtoType>(); 4111 if (getLangOpts().CPlusPlus17 && 4112 isUnresolvedExceptionSpec(SpecializationFPT->getExceptionSpecType()) && 4113 !ResolveExceptionSpec(Info.getLocation(), SpecializationFPT)) 4114 return TDK_MiscellaneousDeductionFailure; 4115 4116 // Adjust the exception specification of the argument to match the 4117 // substituted and resolved type we just formed. (Calling convention and 4118 // noreturn can't be dependent, so we don't actually need this for them 4119 // right now.) 4120 QualType SpecializationType = Specialization->getType(); 4121 if (!IsAddressOfFunction) 4122 ArgFunctionType = adjustCCAndNoReturn(ArgFunctionType, SpecializationType, 4123 /*AdjustExceptionSpec*/true); 4124 4125 // If the requested function type does not match the actual type of the 4126 // specialization with respect to arguments of compatible pointer to function 4127 // types, template argument deduction fails. 4128 if (!ArgFunctionType.isNull()) { 4129 if (IsAddressOfFunction && 4130 !isSameOrCompatibleFunctionType( 4131 Context.getCanonicalType(SpecializationType), 4132 Context.getCanonicalType(ArgFunctionType))) 4133 return TDK_MiscellaneousDeductionFailure; 4134 4135 if (!IsAddressOfFunction && 4136 !Context.hasSameType(SpecializationType, ArgFunctionType)) 4137 return TDK_MiscellaneousDeductionFailure; 4138 } 4139 4140 return TDK_Success; 4141} 4142 4143/// Deduce template arguments for a templated conversion 4144/// function (C++ [temp.deduct.conv]) and, if successful, produce a 4145/// conversion function template specialization. 4146Sema::TemplateDeductionResult 4147Sema::DeduceTemplateArguments(FunctionTemplateDecl *ConversionTemplate, 4148 QualType ToType, 4149 CXXConversionDecl *&Specialization, 4150 TemplateDeductionInfo &Info) { 4151 if (ConversionTemplate->isInvalidDecl()) 4152 return TDK_Invalid; 4153 4154 CXXConversionDecl *ConversionGeneric 4155 = cast<CXXConversionDecl>(ConversionTemplate->getTemplatedDecl()); 4156 4157 QualType FromType = ConversionGeneric->getConversionType(); 4158 4159 // Canonicalize the types for deduction. 4160 QualType P = Context.getCanonicalType(FromType); 4161 QualType A = Context.getCanonicalType(ToType); 4162 4163 // C++0x [temp.deduct.conv]p2: 4164 // If P is a reference type, the type referred to by P is used for 4165 // type deduction. 4166 if (const ReferenceType *PRef = P->getAs<ReferenceType>()) 4167 P = PRef->getPointeeType(); 4168 4169 // C++0x [temp.deduct.conv]p4: 4170 // [...] If A is a reference type, the type referred to by A is used 4171 // for type deduction. 4172 if (const ReferenceType *ARef = A->getAs<ReferenceType>()) { 4173 A = ARef->getPointeeType(); 4174 // We work around a defect in the standard here: cv-qualifiers are also 4175 // removed from P and A in this case, unless P was a reference type. This 4176 // seems to mostly match what other compilers are doing. 4177 if (!FromType->getAs<ReferenceType>()) { 4178 A = A.getUnqualifiedType(); 4179 P = P.getUnqualifiedType(); 4180 } 4181 4182 // C++ [temp.deduct.conv]p3: 4183 // 4184 // If A is not a reference type: 4185 } else { 4186 assert(!A->isReferenceType() && "Reference types were handled above")((!A->isReferenceType() && "Reference types were handled above"
) ? static_cast<void> (0) : __assert_fail ("!A->isReferenceType() && \"Reference types were handled above\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4186, __PRETTY_FUNCTION__)); 4187 4188 // - If P is an array type, the pointer type produced by the 4189 // array-to-pointer standard conversion (4.2) is used in place 4190 // of P for type deduction; otherwise, 4191 if (P->isArrayType()) 4192 P = Context.getArrayDecayedType(P); 4193 // - If P is a function type, the pointer type produced by the 4194 // function-to-pointer standard conversion (4.3) is used in 4195 // place of P for type deduction; otherwise, 4196 else if (P->isFunctionType()) 4197 P = Context.getPointerType(P); 4198 // - If P is a cv-qualified type, the top level cv-qualifiers of 4199 // P's type are ignored for type deduction. 4200 else 4201 P = P.getUnqualifiedType(); 4202 4203 // C++0x [temp.deduct.conv]p4: 4204 // If A is a cv-qualified type, the top level cv-qualifiers of A's 4205 // type are ignored for type deduction. If A is a reference type, the type 4206 // referred to by A is used for type deduction. 4207 A = A.getUnqualifiedType(); 4208 } 4209 4210 // Unevaluated SFINAE context. 4211 EnterExpressionEvaluationContext Unevaluated( 4212 *this, Sema::ExpressionEvaluationContext::Unevaluated); 4213 SFINAETrap Trap(*this); 4214 4215 // C++ [temp.deduct.conv]p1: 4216 // Template argument deduction is done by comparing the return 4217 // type of the template conversion function (call it P) with the 4218 // type that is required as the result of the conversion (call it 4219 // A) as described in 14.8.2.4. 4220 TemplateParameterList *TemplateParams 4221 = ConversionTemplate->getTemplateParameters(); 4222 SmallVector<DeducedTemplateArgument, 4> Deduced; 4223 Deduced.resize(TemplateParams->size()); 4224 4225 // C++0x [temp.deduct.conv]p4: 4226 // In general, the deduction process attempts to find template 4227 // argument values that will make the deduced A identical to 4228 // A. However, there are two cases that allow a difference: 4229 unsigned TDF = 0; 4230 // - If the original A is a reference type, A can be more 4231 // cv-qualified than the deduced A (i.e., the type referred to 4232 // by the reference) 4233 if (ToType->isReferenceType()) 4234 TDF |= TDF_ArgWithReferenceType; 4235 // - The deduced A can be another pointer or pointer to member 4236 // type that can be converted to A via a qualification 4237 // conversion. 4238 // 4239 // (C++0x [temp.deduct.conv]p6 clarifies that this only happens when 4240 // both P and A are pointers or member pointers. In this case, we 4241 // just ignore cv-qualifiers completely). 4242 if ((P->isPointerType() && A->isPointerType()) || 4243 (P->isMemberPointerType() && A->isMemberPointerType())) 4244 TDF |= TDF_IgnoreQualifiers; 4245 if (TemplateDeductionResult Result 4246 = DeduceTemplateArgumentsByTypeMatch(*this, TemplateParams, 4247 P, A, Info, Deduced, TDF)) 4248 return Result; 4249 4250 // Create an Instantiation Scope for finalizing the operator. 4251 LocalInstantiationScope InstScope(*this); 4252 // Finish template argument deduction. 4253 FunctionDecl *ConversionSpecialized = nullptr; 4254 TemplateDeductionResult Result 4255 = FinishTemplateArgumentDeduction(ConversionTemplate, Deduced, 0, 4256 ConversionSpecialized, Info); 4257 Specialization = cast_or_null<CXXConversionDecl>(ConversionSpecialized); 4258 return Result; 4259} 4260 4261/// Deduce template arguments for a function template when there is 4262/// nothing to deduce against (C++0x [temp.arg.explicit]p3). 4263/// 4264/// \param FunctionTemplate the function template for which we are performing 4265/// template argument deduction. 4266/// 4267/// \param ExplicitTemplateArgs the explicitly-specified template 4268/// arguments. 4269/// 4270/// \param Specialization if template argument deduction was successful, 4271/// this will be set to the function template specialization produced by 4272/// template argument deduction. 4273/// 4274/// \param Info the argument will be updated to provide additional information 4275/// about template argument deduction. 4276/// 4277/// \param IsAddressOfFunction If \c true, we are deducing as part of taking 4278/// the address of a function template in a context where we do not have a 4279/// target type, per [over.over]. If \c false, we are looking up a function 4280/// template specialization based on its signature, which only happens when 4281/// deducing a function parameter type from an argument that is a template-id 4282/// naming a function template specialization. 4283/// 4284/// \returns the result of template argument deduction. 4285Sema::TemplateDeductionResult Sema::DeduceTemplateArguments( 4286 FunctionTemplateDecl *FunctionTemplate, 4287 TemplateArgumentListInfo *ExplicitTemplateArgs, 4288 FunctionDecl *&Specialization, TemplateDeductionInfo &Info, 4289 bool IsAddressOfFunction) { 4290 return DeduceTemplateArguments(FunctionTemplate, ExplicitTemplateArgs, 4291 QualType(), Specialization, Info, 4292 IsAddressOfFunction); 4293} 4294 4295namespace { 4296 struct DependentAuto { bool IsPack; }; 4297 4298 /// Substitute the 'auto' specifier or deduced template specialization type 4299 /// specifier within a type for a given replacement type. 4300 class SubstituteDeducedTypeTransform : 4301 public TreeTransform<SubstituteDeducedTypeTransform> { 4302 QualType Replacement; 4303 bool ReplacementIsPack; 4304 bool UseTypeSugar; 4305 4306 public: 4307 SubstituteDeducedTypeTransform(Sema &SemaRef, DependentAuto DA) 4308 : TreeTransform<SubstituteDeducedTypeTransform>(SemaRef), Replacement(), 4309 ReplacementIsPack(DA.IsPack), UseTypeSugar(true) {} 4310 4311 SubstituteDeducedTypeTransform(Sema &SemaRef, QualType Replacement, 4312 bool UseTypeSugar = true) 4313 : TreeTransform<SubstituteDeducedTypeTransform>(SemaRef), 4314 Replacement(Replacement), ReplacementIsPack(false), 4315 UseTypeSugar(UseTypeSugar) {} 4316 4317 QualType TransformDesugared(TypeLocBuilder &TLB, DeducedTypeLoc TL) { 4318 assert(isa<TemplateTypeParmType>(Replacement) &&((isa<TemplateTypeParmType>(Replacement) && "unexpected unsugared replacement kind"
) ? static_cast<void> (0) : __assert_fail ("isa<TemplateTypeParmType>(Replacement) && \"unexpected unsugared replacement kind\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4319, __PRETTY_FUNCTION__)) 4319 "unexpected unsugared replacement kind")((isa<TemplateTypeParmType>(Replacement) && "unexpected unsugared replacement kind"
) ? static_cast<void> (0) : __assert_fail ("isa<TemplateTypeParmType>(Replacement) && \"unexpected unsugared replacement kind\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4319, __PRETTY_FUNCTION__)); 4320 QualType Result = Replacement; 4321 TemplateTypeParmTypeLoc NewTL = TLB.push<TemplateTypeParmTypeLoc>(Result); 4322 NewTL.setNameLoc(TL.getNameLoc()); 4323 return Result; 4324 } 4325 4326 QualType TransformAutoType(TypeLocBuilder &TLB, AutoTypeLoc TL) { 4327 // If we're building the type pattern to deduce against, don't wrap the 4328 // substituted type in an AutoType. Certain template deduction rules 4329 // apply only when a template type parameter appears directly (and not if 4330 // the parameter is found through desugaring). For instance: 4331 // auto &&lref = lvalue; 4332 // must transform into "rvalue reference to T" not "rvalue reference to 4333 // auto type deduced as T" in order for [temp.deduct.call]p3 to apply. 4334 // 4335 // FIXME: Is this still necessary? 4336 if (!UseTypeSugar) 4337 return TransformDesugared(TLB, TL); 4338 4339 QualType Result = SemaRef.Context.getAutoType( 4340 Replacement, TL.getTypePtr()->getKeyword(), Replacement.isNull(), 4341 ReplacementIsPack); 4342 auto NewTL = TLB.push<AutoTypeLoc>(Result); 4343 NewTL.setNameLoc(TL.getNameLoc()); 4344 return Result; 4345 } 4346 4347 QualType TransformDeducedTemplateSpecializationType( 4348 TypeLocBuilder &TLB, DeducedTemplateSpecializationTypeLoc TL) { 4349 if (!UseTypeSugar) 4350 return TransformDesugared(TLB, TL); 4351 4352 QualType Result = SemaRef.Context.getDeducedTemplateSpecializationType( 4353 TL.getTypePtr()->getTemplateName(), 4354 Replacement, Replacement.isNull()); 4355 auto NewTL = TLB.push<DeducedTemplateSpecializationTypeLoc>(Result); 4356 NewTL.setNameLoc(TL.getNameLoc()); 4357 return Result; 4358 } 4359 4360 ExprResult TransformLambdaExpr(LambdaExpr *E) { 4361 // Lambdas never need to be transformed. 4362 return E; 4363 } 4364 4365 QualType Apply(TypeLoc TL) { 4366 // Create some scratch storage for the transformed type locations. 4367 // FIXME: We're just going to throw this information away. Don't build it. 4368 TypeLocBuilder TLB; 4369 TLB.reserve(TL.getFullDataSize()); 4370 return TransformType(TLB, TL); 4371 } 4372 }; 4373 4374} // namespace 4375 4376Sema::DeduceAutoResult 4377Sema::DeduceAutoType(TypeSourceInfo *Type, Expr *&Init, QualType &Result, 4378 Optional<unsigned> DependentDeductionDepth) { 4379 return DeduceAutoType(Type->getTypeLoc(), Init, Result, 4380 DependentDeductionDepth); 4381} 4382 4383/// Attempt to produce an informative diagostic explaining why auto deduction 4384/// failed. 4385/// \return \c true if diagnosed, \c false if not. 4386static bool diagnoseAutoDeductionFailure(Sema &S, 4387 Sema::TemplateDeductionResult TDK, 4388 TemplateDeductionInfo &Info, 4389 ArrayRef<SourceRange> Ranges) { 4390 switch (TDK) { 4391 case Sema::TDK_Inconsistent: { 4392 // Inconsistent deduction means we were deducing from an initializer list. 4393 auto D = S.Diag(Info.getLocation(), diag::err_auto_inconsistent_deduction); 4394 D << Info.FirstArg << Info.SecondArg; 4395 for (auto R : Ranges) 4396 D << R; 4397 return true; 4398 } 4399 4400 // FIXME: Are there other cases for which a custom diagnostic is more useful 4401 // than the basic "types don't match" diagnostic? 4402 4403 default: 4404 return false; 4405 } 4406} 4407 4408/// Deduce the type for an auto type-specifier (C++11 [dcl.spec.auto]p6) 4409/// 4410/// Note that this is done even if the initializer is dependent. (This is 4411/// necessary to support partial ordering of templates using 'auto'.) 4412/// A dependent type will be produced when deducing from a dependent type. 4413/// 4414/// \param Type the type pattern using the auto type-specifier. 4415/// \param Init the initializer for the variable whose type is to be deduced. 4416/// \param Result if type deduction was successful, this will be set to the 4417/// deduced type. 4418/// \param DependentDeductionDepth Set if we should permit deduction in 4419/// dependent cases. This is necessary for template partial ordering with 4420/// 'auto' template parameters. The value specified is the template 4421/// parameter depth at which we should perform 'auto' deduction. 4422Sema::DeduceAutoResult 4423Sema::DeduceAutoType(TypeLoc Type, Expr *&Init, QualType &Result, 4424 Optional<unsigned> DependentDeductionDepth) { 4425 if (Init->getType()->isNonOverloadPlaceholderType()) { 4426 ExprResult NonPlaceholder = CheckPlaceholderExpr(Init); 4427 if (NonPlaceholder.isInvalid()) 4428 return DAR_FailedAlreadyDiagnosed; 4429 Init = NonPlaceholder.get(); 4430 } 4431 4432 DependentAuto DependentResult = { 4433 /*.IsPack = */ (bool)Type.getAs<PackExpansionTypeLoc>()}; 4434 4435 if (!DependentDeductionDepth && 4436 (Type.getType()->isDependentType() || Init->isTypeDependent())) { 4437 Result = SubstituteDeducedTypeTransform(*this, DependentResult).Apply(Type); 4438 assert(!Result.isNull() && "substituting DependentTy can't fail")((!Result.isNull() && "substituting DependentTy can't fail"
) ? static_cast<void> (0) : __assert_fail ("!Result.isNull() && \"substituting DependentTy can't fail\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4438, __PRETTY_FUNCTION__)); 4439 return DAR_Succeeded; 4440 } 4441 4442 // Find the depth of template parameter to synthesize. 4443 unsigned Depth = DependentDeductionDepth.getValueOr(0); 4444 4445 // If this is a 'decltype(auto)' specifier, do the decltype dance. 4446 // Since 'decltype(auto)' can only occur at the top of the type, we 4447 // don't need to go digging for it. 4448 if (const AutoType *AT = Type.getType()->getAs<AutoType>()) { 4449 if (AT->isDecltypeAuto()) { 4450 if (isa<InitListExpr>(Init)) { 4451 Diag(Init->getBeginLoc(), diag::err_decltype_auto_initializer_list); 4452 return DAR_FailedAlreadyDiagnosed; 4453 } 4454 4455 ExprResult ER = CheckPlaceholderExpr(Init); 4456 if (ER.isInvalid()) 4457 return DAR_FailedAlreadyDiagnosed; 4458 Init = ER.get(); 4459 QualType Deduced = BuildDecltypeType(Init, Init->getBeginLoc(), false); 4460 if (Deduced.isNull()) 4461 return DAR_FailedAlreadyDiagnosed; 4462 // FIXME: Support a non-canonical deduced type for 'auto'. 4463 Deduced = Context.getCanonicalType(Deduced); 4464 Result = SubstituteDeducedTypeTransform(*this, Deduced).Apply(Type); 4465 if (Result.isNull()) 4466 return DAR_FailedAlreadyDiagnosed; 4467 return DAR_Succeeded; 4468 } else if (!getLangOpts().CPlusPlus) { 4469 if (isa<InitListExpr>(Init)) { 4470 Diag(Init->getBeginLoc(), diag::err_auto_init_list_from_c); 4471 return DAR_FailedAlreadyDiagnosed; 4472 } 4473 } 4474 } 4475 4476 SourceLocation Loc = Init->getExprLoc(); 4477 4478 LocalInstantiationScope InstScope(*this); 4479 4480 // Build template<class TemplParam> void Func(FuncParam); 4481 TemplateTypeParmDecl *TemplParam = TemplateTypeParmDecl::Create( 4482 Context, nullptr, SourceLocation(), Loc, Depth, 0, nullptr, false, false); 4483 QualType TemplArg = QualType(TemplParam->getTypeForDecl(), 0); 4484 NamedDecl *TemplParamPtr = TemplParam; 4485 FixedSizeTemplateParameterListStorage<1, false> TemplateParamsSt( 4486 Loc, Loc, TemplParamPtr, Loc, nullptr); 4487 4488 QualType FuncParam = 4489 SubstituteDeducedTypeTransform(*this, TemplArg, /*UseTypeSugar*/false) 4490 .Apply(Type); 4491 assert(!FuncParam.isNull() &&((!FuncParam.isNull() && "substituting template parameter for 'auto' failed"
) ? static_cast<void> (0) : __assert_fail ("!FuncParam.isNull() && \"substituting template parameter for 'auto' failed\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4492, __PRETTY_FUNCTION__)) 4492 "substituting template parameter for 'auto' failed")((!FuncParam.isNull() && "substituting template parameter for 'auto' failed"
) ? static_cast<void> (0) : __assert_fail ("!FuncParam.isNull() && \"substituting template parameter for 'auto' failed\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4492, __PRETTY_FUNCTION__)); 4493 4494 // Deduce type of TemplParam in Func(Init) 4495 SmallVector<DeducedTemplateArgument, 1> Deduced; 4496 Deduced.resize(1); 4497 4498 TemplateDeductionInfo Info(Loc, Depth); 4499 4500 // If deduction failed, don't diagnose if the initializer is dependent; it 4501 // might acquire a matching type in the instantiation. 4502 auto DeductionFailed = [&](TemplateDeductionResult TDK, 4503 ArrayRef<SourceRange> Ranges) -> DeduceAutoResult { 4504 if (Init->isTypeDependent()) { 4505 Result = 4506 SubstituteDeducedTypeTransform(*this, DependentResult).Apply(Type); 4507 assert(!Result.isNull() && "substituting DependentTy can't fail")((!Result.isNull() && "substituting DependentTy can't fail"
) ? static_cast<void> (0) : __assert_fail ("!Result.isNull() && \"substituting DependentTy can't fail\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4507, __PRETTY_FUNCTION__)); 4508 return DAR_Succeeded; 4509 } 4510 if (diagnoseAutoDeductionFailure(*this, TDK, Info, Ranges)) 4511 return DAR_FailedAlreadyDiagnosed; 4512 return DAR_Failed; 4513 }; 4514 4515 SmallVector<OriginalCallArg, 4> OriginalCallArgs; 4516 4517 InitListExpr *InitList = dyn_cast<InitListExpr>(Init); 4518 if (InitList) { 4519 // Notionally, we substitute std::initializer_list<T> for 'auto' and deduce 4520 // against that. Such deduction only succeeds if removing cv-qualifiers and 4521 // references results in std::initializer_list<T>. 4522 if (!Type.getType().getNonReferenceType()->getAs<AutoType>()) 4523 return DAR_Failed; 4524 4525 // Resolving a core issue: a braced-init-list containing any designators is 4526 // a non-deduced context. 4527 for (Expr *E : InitList->inits()) 4528 if (isa<DesignatedInitExpr>(E)) 4529 return DAR_Failed; 4530 4531 SourceRange DeducedFromInitRange; 4532 for (unsigned i = 0, e = InitList->getNumInits(); i < e; ++i) { 4533 Expr *Init = InitList->getInit(i); 4534 4535 if (auto TDK = DeduceTemplateArgumentsFromCallArgument( 4536 *this, TemplateParamsSt.get(), 0, TemplArg, Init, 4537 Info, Deduced, OriginalCallArgs, /*Decomposed*/ true, 4538 /*ArgIdx*/ 0, /*TDF*/ 0)) 4539 return DeductionFailed(TDK, {DeducedFromInitRange, 4540 Init->getSourceRange()}); 4541 4542 if (DeducedFromInitRange.isInvalid() && 4543 Deduced[0].getKind() != TemplateArgument::Null) 4544 DeducedFromInitRange = Init->getSourceRange(); 4545 } 4546 } else { 4547 if (!getLangOpts().CPlusPlus && Init->refersToBitField()) { 4548 Diag(Loc, diag::err_auto_bitfield); 4549 return DAR_FailedAlreadyDiagnosed; 4550 } 4551 4552 if (auto TDK = DeduceTemplateArgumentsFromCallArgument( 4553 *this, TemplateParamsSt.get(), 0, FuncParam, Init, Info, Deduced, 4554 OriginalCallArgs, /*Decomposed*/ false, /*ArgIdx*/ 0, /*TDF*/ 0)) 4555 return DeductionFailed(TDK, {}); 4556 } 4557 4558 // Could be null if somehow 'auto' appears in a non-deduced context. 4559 if (Deduced[0].getKind() != TemplateArgument::Type) 4560 return DeductionFailed(TDK_Incomplete, {}); 4561 4562 QualType DeducedType = Deduced[0].getAsType(); 4563 4564 if (InitList) { 4565 DeducedType = BuildStdInitializerList(DeducedType, Loc); 4566 if (DeducedType.isNull()) 4567 return DAR_FailedAlreadyDiagnosed; 4568 } 4569 4570 Result = SubstituteDeducedTypeTransform(*this, DeducedType).Apply(Type); 4571 if (Result.isNull()) 4572 return DAR_FailedAlreadyDiagnosed; 4573 4574 // Check that the deduced argument type is compatible with the original 4575 // argument type per C++ [temp.deduct.call]p4. 4576 QualType DeducedA = InitList ? Deduced[0].getAsType() : Result; 4577 for (const OriginalCallArg &OriginalArg : OriginalCallArgs) { 4578 assert((bool)InitList == OriginalArg.DecomposedParam &&(((bool)InitList == OriginalArg.DecomposedParam && "decomposed non-init-list in auto deduction?"
) ? static_cast<void> (0) : __assert_fail ("(bool)InitList == OriginalArg.DecomposedParam && \"decomposed non-init-list in auto deduction?\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4579, __PRETTY_FUNCTION__)) 4579 "decomposed non-init-list in auto deduction?")(((bool)InitList == OriginalArg.DecomposedParam && "decomposed non-init-list in auto deduction?"
) ? static_cast<void> (0) : __assert_fail ("(bool)InitList == OriginalArg.DecomposedParam && \"decomposed non-init-list in auto deduction?\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4579, __PRETTY_FUNCTION__)); 4580 if (auto TDK = 4581 CheckOriginalCallArgDeduction(*this, Info, OriginalArg, DeducedA)) { 4582 Result = QualType(); 4583 return DeductionFailed(TDK, {}); 4584 } 4585 } 4586 4587 return DAR_Succeeded; 4588} 4589 4590QualType Sema::SubstAutoType(QualType TypeWithAuto, 4591 QualType TypeToReplaceAuto) { 4592 if (TypeToReplaceAuto->isDependentType()) 4593 return SubstituteDeducedTypeTransform( 4594 *this, DependentAuto{ 4595 TypeToReplaceAuto->containsUnexpandedParameterPack()}) 4596 .TransformType(TypeWithAuto); 4597 return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto) 4598 .TransformType(TypeWithAuto); 4599} 4600 4601TypeSourceInfo *Sema::SubstAutoTypeSourceInfo(TypeSourceInfo *TypeWithAuto, 4602 QualType TypeToReplaceAuto) { 4603 if (TypeToReplaceAuto->isDependentType()) 4604 return SubstituteDeducedTypeTransform( 4605 *this, 4606 DependentAuto{ 4607 TypeToReplaceAuto->containsUnexpandedParameterPack()}) 4608 .TransformType(TypeWithAuto); 4609 return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto) 4610 .TransformType(TypeWithAuto); 4611} 4612 4613QualType Sema::ReplaceAutoType(QualType TypeWithAuto, 4614 QualType TypeToReplaceAuto) { 4615 return SubstituteDeducedTypeTransform(*this, TypeToReplaceAuto, 4616 /*UseTypeSugar*/ false) 4617 .TransformType(TypeWithAuto); 4618} 4619 4620void Sema::DiagnoseAutoDeductionFailure(VarDecl *VDecl, Expr *Init) { 4621 if (isa<InitListExpr>(Init)) 4622 Diag(VDecl->getLocation(), 4623 VDecl->isInitCapture() 4624 ? diag::err_init_capture_deduction_failure_from_init_list 4625 : diag::err_auto_var_deduction_failure_from_init_list) 4626 << VDecl->getDeclName() << VDecl->getType() << Init->getSourceRange(); 4627 else 4628 Diag(VDecl->getLocation(), 4629 VDecl->isInitCapture() ? diag::err_init_capture_deduction_failure 4630 : diag::err_auto_var_deduction_failure) 4631 << VDecl->getDeclName() << VDecl->getType() << Init->getType() 4632 << Init->getSourceRange(); 4633} 4634 4635bool Sema::DeduceReturnType(FunctionDecl *FD, SourceLocation Loc, 4636 bool Diagnose) { 4637 assert(FD->getReturnType()->isUndeducedType())((FD->getReturnType()->isUndeducedType()) ? static_cast
<void> (0) : __assert_fail ("FD->getReturnType()->isUndeducedType()"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4637, __PRETTY_FUNCTION__)); 4638 4639 // For a lambda's conversion operator, deduce any 'auto' or 'decltype(auto)' 4640 // within the return type from the call operator's type. 4641 if (isLambdaConversionOperator(FD)) { 4642 CXXRecordDecl *Lambda = cast<CXXMethodDecl>(FD)->getParent(); 4643 FunctionDecl *CallOp = Lambda->getLambdaCallOperator(); 4644 4645 // For a generic lambda, instantiate the call operator if needed. 4646 if (auto *Args = FD->getTemplateSpecializationArgs()) { 4647 CallOp = InstantiateFunctionDeclaration( 4648 CallOp->getDescribedFunctionTemplate(), Args, Loc); 4649 if (!CallOp || CallOp->isInvalidDecl()) 4650 return true; 4651 4652 // We might need to deduce the return type by instantiating the definition 4653 // of the operator() function. 4654 if (CallOp->getReturnType()->isUndeducedType()) { 4655 runWithSufficientStackSpace(Loc, [&] { 4656 InstantiateFunctionDefinition(Loc, CallOp); 4657 }); 4658 } 4659 } 4660 4661 if (CallOp->isInvalidDecl()) 4662 return true; 4663 assert(!CallOp->getReturnType()->isUndeducedType() &&((!CallOp->getReturnType()->isUndeducedType() &&
"failed to deduce lambda return type") ? static_cast<void
> (0) : __assert_fail ("!CallOp->getReturnType()->isUndeducedType() && \"failed to deduce lambda return type\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4664, __PRETTY_FUNCTION__)) 4664 "failed to deduce lambda return type")((!CallOp->getReturnType()->isUndeducedType() &&
"failed to deduce lambda return type") ? static_cast<void
> (0) : __assert_fail ("!CallOp->getReturnType()->isUndeducedType() && \"failed to deduce lambda return type\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4664, __PRETTY_FUNCTION__)); 4665 4666 // Build the new return type from scratch. 4667 QualType RetType = getLambdaConversionFunctionResultType( 4668 CallOp->getType()->castAs<FunctionProtoType>()); 4669 if (FD->getReturnType()->getAs<PointerType>()) 4670 RetType = Context.getPointerType(RetType); 4671 else { 4672 assert(FD->getReturnType()->getAs<BlockPointerType>())((FD->getReturnType()->getAs<BlockPointerType>())
? static_cast<void> (0) : __assert_fail ("FD->getReturnType()->getAs<BlockPointerType>()"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4672, __PRETTY_FUNCTION__)); 4673 RetType = Context.getBlockPointerType(RetType); 4674 } 4675 Context.adjustDeducedFunctionResultType(FD, RetType); 4676 return false; 4677 } 4678 4679 if (FD->getTemplateInstantiationPattern()) { 4680 runWithSufficientStackSpace(Loc, [&] { 4681 InstantiateFunctionDefinition(Loc, FD); 4682 }); 4683 } 4684 4685 bool StillUndeduced = FD->getReturnType()->isUndeducedType(); 4686 if (StillUndeduced && Diagnose && !FD->isInvalidDecl()) { 4687 Diag(Loc, diag::err_auto_fn_used_before_defined) << FD; 4688 Diag(FD->getLocation(), diag::note_callee_decl) << FD; 4689 } 4690 4691 return StillUndeduced; 4692} 4693 4694/// If this is a non-static member function, 4695static void 4696AddImplicitObjectParameterType(ASTContext &Context, 4697 CXXMethodDecl *Method, 4698 SmallVectorImpl<QualType> &ArgTypes) { 4699 // C++11 [temp.func.order]p3: 4700 // [...] The new parameter is of type "reference to cv A," where cv are 4701 // the cv-qualifiers of the function template (if any) and A is 4702 // the class of which the function template is a member. 4703 // 4704 // The standard doesn't say explicitly, but we pick the appropriate kind of 4705 // reference type based on [over.match.funcs]p4. 4706 QualType ArgTy = Context.getTypeDeclType(Method->getParent()); 4707 ArgTy = Context.getQualifiedType(ArgTy, Method->getMethodQualifiers()); 4708 if (Method->getRefQualifier() == RQ_RValue) 4709 ArgTy = Context.getRValueReferenceType(ArgTy); 4710 else 4711 ArgTy = Context.getLValueReferenceType(ArgTy); 4712 ArgTypes.push_back(ArgTy); 4713} 4714 4715/// Determine whether the function template \p FT1 is at least as 4716/// specialized as \p FT2. 4717static bool isAtLeastAsSpecializedAs(Sema &S, 4718 SourceLocation Loc, 4719 FunctionTemplateDecl *FT1, 4720 FunctionTemplateDecl *FT2, 4721 TemplatePartialOrderingContext TPOC, 4722 unsigned NumCallArguments1) { 4723 FunctionDecl *FD1 = FT1->getTemplatedDecl(); 4724 FunctionDecl *FD2 = FT2->getTemplatedDecl(); 4725 const FunctionProtoType *Proto1 = FD1->getType()->getAs<FunctionProtoType>(); 4726 const FunctionProtoType *Proto2 = FD2->getType()->getAs<FunctionProtoType>(); 4727 4728 assert(Proto1 && Proto2 && "Function templates must have prototypes")((Proto1 && Proto2 && "Function templates must have prototypes"
) ? static_cast<void> (0) : __assert_fail ("Proto1 && Proto2 && \"Function templates must have prototypes\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4728, __PRETTY_FUNCTION__)); 4729 TemplateParameterList *TemplateParams = FT2->getTemplateParameters(); 4730 SmallVector<DeducedTemplateArgument, 4> Deduced; 4731 Deduced.resize(TemplateParams->size()); 4732 4733 // C++0x [temp.deduct.partial]p3: 4734 // The types used to determine the ordering depend on the context in which 4735 // the partial ordering is done: 4736 TemplateDeductionInfo Info(Loc); 4737 SmallVector<QualType, 4> Args2; 4738 switch (TPOC) { 4739 case TPOC_Call: { 4740 // - In the context of a function call, the function parameter types are 4741 // used. 4742 CXXMethodDecl *Method1 = dyn_cast<CXXMethodDecl>(FD1); 4743 CXXMethodDecl *Method2 = dyn_cast<CXXMethodDecl>(FD2); 4744 4745 // C++11 [temp.func.order]p3: 4746 // [...] If only one of the function templates is a non-static 4747 // member, that function template is considered to have a new 4748 // first parameter inserted in its function parameter list. The 4749 // new parameter is of type "reference to cv A," where cv are 4750 // the cv-qualifiers of the function template (if any) and A is 4751 // the class of which the function template is a member. 4752 // 4753 // Note that we interpret this to mean "if one of the function 4754 // templates is a non-static member and the other is a non-member"; 4755 // otherwise, the ordering rules for static functions against non-static 4756 // functions don't make any sense. 4757 // 4758 // C++98/03 doesn't have this provision but we've extended DR532 to cover 4759 // it as wording was broken prior to it. 4760 SmallVector<QualType, 4> Args1; 4761 4762 unsigned NumComparedArguments = NumCallArguments1; 4763 4764 if (!Method2 && Method1 && !Method1->isStatic()) { 4765 // Compare 'this' from Method1 against first parameter from Method2. 4766 AddImplicitObjectParameterType(S.Context, Method1, Args1); 4767 ++NumComparedArguments; 4768 } else if (!Method1 && Method2 && !Method2->isStatic()) { 4769 // Compare 'this' from Method2 against first parameter from Method1. 4770 AddImplicitObjectParameterType(S.Context, Method2, Args2); 4771 } 4772 4773 Args1.insert(Args1.end(), Proto1->param_type_begin(), 4774 Proto1->param_type_end()); 4775 Args2.insert(Args2.end(), Proto2->param_type_begin(), 4776 Proto2->param_type_end()); 4777 4778 // C++ [temp.func.order]p5: 4779 // The presence of unused ellipsis and default arguments has no effect on 4780 // the partial ordering of function templates. 4781 if (Args1.size() > NumComparedArguments) 4782 Args1.resize(NumComparedArguments); 4783 if (Args2.size() > NumComparedArguments) 4784 Args2.resize(NumComparedArguments); 4785 if (DeduceTemplateArguments(S, TemplateParams, Args2.data(), Args2.size(), 4786 Args1.data(), Args1.size(), Info, Deduced, 4787 TDF_None, /*PartialOrdering=*/true)) 4788 return false; 4789 4790 break; 4791 } 4792 4793 case TPOC_Conversion: 4794 // - In the context of a call to a conversion operator, the return types 4795 // of the conversion function templates are used. 4796 if (DeduceTemplateArgumentsByTypeMatch( 4797 S, TemplateParams, Proto2->getReturnType(), Proto1->getReturnType(), 4798 Info, Deduced, TDF_None, 4799 /*PartialOrdering=*/true)) 4800 return false; 4801 break; 4802 4803 case TPOC_Other: 4804 // - In other contexts (14.6.6.2) the function template's function type 4805 // is used. 4806 if (DeduceTemplateArgumentsByTypeMatch(S, TemplateParams, 4807 FD2->getType(), FD1->getType(), 4808 Info, Deduced, TDF_None, 4809 /*PartialOrdering=*/true)) 4810 return false; 4811 break; 4812 } 4813 4814 // C++0x [temp.deduct.partial]p11: 4815 // In most cases, all template parameters must have values in order for 4816 // deduction to succeed, but for partial ordering purposes a template 4817 // parameter may remain without a value provided it is not used in the 4818 // types being used for partial ordering. [ Note: a template parameter used 4819 // in a non-deduced context is considered used. -end note] 4820 unsigned ArgIdx = 0, NumArgs = Deduced.size(); 4821 for (; ArgIdx != NumArgs; ++ArgIdx) 4822 if (Deduced[ArgIdx].isNull()) 4823 break; 4824 4825 // FIXME: We fail to implement [temp.deduct.type]p1 along this path. We need 4826 // to substitute the deduced arguments back into the template and check that 4827 // we get the right type. 4828 4829 if (ArgIdx == NumArgs) { 4830 // All template arguments were deduced. FT1 is at least as specialized 4831 // as FT2. 4832 return true; 4833 } 4834 4835 // Figure out which template parameters were used. 4836 llvm::SmallBitVector UsedParameters(TemplateParams->size()); 4837 switch (TPOC) { 4838 case TPOC_Call: 4839 for (unsigned I = 0, N = Args2.size(); I != N; ++I) 4840 ::MarkUsedTemplateParameters(S.Context, Args2[I], false, 4841 TemplateParams->getDepth(), 4842 UsedParameters); 4843 break; 4844 4845 case TPOC_Conversion: 4846 ::MarkUsedTemplateParameters(S.Context, Proto2->getReturnType(), false, 4847 TemplateParams->getDepth(), UsedParameters); 4848 break; 4849 4850 case TPOC_Other: 4851 ::MarkUsedTemplateParameters(S.Context, FD2->getType(), false, 4852 TemplateParams->getDepth(), 4853 UsedParameters); 4854 break; 4855 } 4856 4857 for (; ArgIdx != NumArgs; ++ArgIdx) 4858 // If this argument had no value deduced but was used in one of the types 4859 // used for partial ordering, then deduction fails. 4860 if (Deduced[ArgIdx].isNull() && UsedParameters[ArgIdx]) 4861 return false; 4862 4863 return true; 4864} 4865 4866/// Determine whether this a function template whose parameter-type-list 4867/// ends with a function parameter pack. 4868static bool isVariadicFunctionTemplate(FunctionTemplateDecl *FunTmpl) { 4869 FunctionDecl *Function = FunTmpl->getTemplatedDecl(); 4870 unsigned NumParams = Function->getNumParams(); 4871 if (NumParams == 0) 4872 return false; 4873 4874 ParmVarDecl *Last = Function->getParamDecl(NumParams - 1); 4875 if (!Last->isParameterPack()) 4876 return false; 4877 4878 // Make sure that no previous parameter is a parameter pack. 4879 while (--NumParams > 0) { 4880 if (Function->getParamDecl(NumParams - 1)->isParameterPack()) 4881 return false; 4882 } 4883 4884 return true; 4885} 4886 4887/// Returns the more specialized function template according 4888/// to the rules of function template partial ordering (C++ [temp.func.order]). 4889/// 4890/// \param FT1 the first function template 4891/// 4892/// \param FT2 the second function template 4893/// 4894/// \param TPOC the context in which we are performing partial ordering of 4895/// function templates. 4896/// 4897/// \param NumCallArguments1 The number of arguments in the call to FT1, used 4898/// only when \c TPOC is \c TPOC_Call. 4899/// 4900/// \param NumCallArguments2 The number of arguments in the call to FT2, used 4901/// only when \c TPOC is \c TPOC_Call. 4902/// 4903/// \returns the more specialized function template. If neither 4904/// template is more specialized, returns NULL. 4905FunctionTemplateDecl * 4906Sema::getMoreSpecializedTemplate(FunctionTemplateDecl *FT1, 4907 FunctionTemplateDecl *FT2, 4908 SourceLocation Loc, 4909 TemplatePartialOrderingContext TPOC, 4910 unsigned NumCallArguments1, 4911 unsigned NumCallArguments2) { 4912 bool Better1 = isAtLeastAsSpecializedAs(*this, Loc, FT1, FT2, TPOC, 4913 NumCallArguments1); 4914 bool Better2 = isAtLeastAsSpecializedAs(*this, Loc, FT2, FT1, TPOC, 4915 NumCallArguments2); 4916 4917 if (Better1 != Better2) // We have a clear winner 4918 return Better1 ? FT1 : FT2; 4919 4920 if (!Better1 && !Better2) // Neither is better than the other 4921 return nullptr; 4922 4923 // FIXME: This mimics what GCC implements, but doesn't match up with the 4924 // proposed resolution for core issue 692. This area needs to be sorted out, 4925 // but for now we attempt to maintain compatibility. 4926 bool Variadic1 = isVariadicFunctionTemplate(FT1); 4927 bool Variadic2 = isVariadicFunctionTemplate(FT2); 4928 if (Variadic1 != Variadic2) 4929 return Variadic1? FT2 : FT1; 4930 4931 return nullptr; 4932} 4933 4934/// Determine if the two templates are equivalent. 4935static bool isSameTemplate(TemplateDecl *T1, TemplateDecl *T2) { 4936 if (T1 == T2) 4937 return true; 4938 4939 if (!T1 || !T2) 4940 return false; 4941 4942 return T1->getCanonicalDecl() == T2->getCanonicalDecl(); 4943} 4944 4945/// Retrieve the most specialized of the given function template 4946/// specializations. 4947/// 4948/// \param SpecBegin the start iterator of the function template 4949/// specializations that we will be comparing. 4950/// 4951/// \param SpecEnd the end iterator of the function template 4952/// specializations, paired with \p SpecBegin. 4953/// 4954/// \param Loc the location where the ambiguity or no-specializations 4955/// diagnostic should occur. 4956/// 4957/// \param NoneDiag partial diagnostic used to diagnose cases where there are 4958/// no matching candidates. 4959/// 4960/// \param AmbigDiag partial diagnostic used to diagnose an ambiguity, if one 4961/// occurs. 4962/// 4963/// \param CandidateDiag partial diagnostic used for each function template 4964/// specialization that is a candidate in the ambiguous ordering. One parameter 4965/// in this diagnostic should be unbound, which will correspond to the string 4966/// describing the template arguments for the function template specialization. 4967/// 4968/// \returns the most specialized function template specialization, if 4969/// found. Otherwise, returns SpecEnd. 4970UnresolvedSetIterator Sema::getMostSpecialized( 4971 UnresolvedSetIterator SpecBegin, UnresolvedSetIterator SpecEnd, 4972 TemplateSpecCandidateSet &FailedCandidates, 4973 SourceLocation Loc, const PartialDiagnostic &NoneDiag, 4974 const PartialDiagnostic &AmbigDiag, const PartialDiagnostic &CandidateDiag, 4975 bool Complain, QualType TargetType) { 4976 if (SpecBegin == SpecEnd) { 4977 if (Complain) { 4978 Diag(Loc, NoneDiag); 4979 FailedCandidates.NoteCandidates(*this, Loc); 4980 } 4981 return SpecEnd; 4982 } 4983 4984 if (SpecBegin + 1 == SpecEnd) 4985 return SpecBegin; 4986 4987 // Find the function template that is better than all of the templates it 4988 // has been compared to. 4989 UnresolvedSetIterator Best = SpecBegin; 4990 FunctionTemplateDecl *BestTemplate 4991 = cast<FunctionDecl>(*Best)->getPrimaryTemplate(); 4992 assert(BestTemplate && "Not a function template specialization?")((BestTemplate && "Not a function template specialization?"
) ? static_cast<void> (0) : __assert_fail ("BestTemplate && \"Not a function template specialization?\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4992, __PRETTY_FUNCTION__)); 4993 for (UnresolvedSetIterator I = SpecBegin + 1; I != SpecEnd; ++I) { 4994 FunctionTemplateDecl *Challenger 4995 = cast<FunctionDecl>(*I)->getPrimaryTemplate(); 4996 assert(Challenger && "Not a function template specialization?")((Challenger && "Not a function template specialization?"
) ? static_cast<void> (0) : __assert_fail ("Challenger && \"Not a function template specialization?\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 4996, __PRETTY_FUNCTION__)); 4997 if (isSameTemplate(getMoreSpecializedTemplate(BestTemplate, Challenger, 4998 Loc, TPOC_Other, 0, 0), 4999 Challenger)) { 5000 Best = I; 5001 BestTemplate = Challenger; 5002 } 5003 } 5004 5005 // Make sure that the "best" function template is more specialized than all 5006 // of the others. 5007 bool Ambiguous = false; 5008 for (UnresolvedSetIterator I = SpecBegin; I != SpecEnd; ++I) { 5009 FunctionTemplateDecl *Challenger 5010 = cast<FunctionDecl>(*I)->getPrimaryTemplate(); 5011 if (I != Best && 5012 !isSameTemplate(getMoreSpecializedTemplate(BestTemplate, Challenger, 5013 Loc, TPOC_Other, 0, 0), 5014 BestTemplate)) { 5015 Ambiguous = true; 5016 break; 5017 } 5018 } 5019 5020 if (!Ambiguous) { 5021 // We found an answer. Return it. 5022 return Best; 5023 } 5024 5025 // Diagnose the ambiguity. 5026 if (Complain) { 5027 Diag(Loc, AmbigDiag); 5028 5029 // FIXME: Can we order the candidates in some sane way? 5030 for (UnresolvedSetIterator I = SpecBegin; I != SpecEnd; ++I) { 5031 PartialDiagnostic PD = CandidateDiag; 5032 const auto *FD = cast<FunctionDecl>(*I); 5033 PD << FD << getTemplateArgumentBindingsText( 5034 FD->getPrimaryTemplate()->getTemplateParameters(), 5035 *FD->getTemplateSpecializationArgs()); 5036 if (!TargetType.isNull()) 5037 HandleFunctionTypeMismatch(PD, FD->getType(), TargetType); 5038 Diag((*I)->getLocation(), PD); 5039 } 5040 } 5041 5042 return SpecEnd; 5043} 5044 5045/// Determine whether one partial specialization, P1, is at least as 5046/// specialized than another, P2. 5047/// 5048/// \tparam TemplateLikeDecl The kind of P2, which must be a 5049/// TemplateDecl or {Class,Var}TemplatePartialSpecializationDecl. 5050/// \param T1 The injected-class-name of P1 (faked for a variable template). 5051/// \param T2 The injected-class-name of P2 (faked for a variable template). 5052template<typename TemplateLikeDecl> 5053static bool isAtLeastAsSpecializedAs(Sema &S, QualType T1, QualType T2, 5054 TemplateLikeDecl *P2, 5055 TemplateDeductionInfo &Info) { 5056 // C++ [temp.class.order]p1: 5057 // For two class template partial specializations, the first is at least as 5058 // specialized as the second if, given the following rewrite to two 5059 // function templates, the first function template is at least as 5060 // specialized as the second according to the ordering rules for function 5061 // templates (14.6.6.2): 5062 // - the first function template has the same template parameters as the 5063 // first partial specialization and has a single function parameter 5064 // whose type is a class template specialization with the template 5065 // arguments of the first partial specialization, and 5066 // - the second function template has the same template parameters as the 5067 // second partial specialization and has a single function parameter 5068 // whose type is a class template specialization with the template 5069 // arguments of the second partial specialization. 5070 // 5071 // Rather than synthesize function templates, we merely perform the 5072 // equivalent partial ordering by performing deduction directly on 5073 // the template arguments of the class template partial 5074 // specializations. This computation is slightly simpler than the 5075 // general problem of function template partial ordering, because 5076 // class template partial specializations are more constrained. We 5077 // know that every template parameter is deducible from the class 5078 // template partial specialization's template arguments, for 5079 // example. 5080 SmallVector<DeducedTemplateArgument, 4> Deduced; 5081 5082 // Determine whether P1 is at least as specialized as P2. 5083 Deduced.resize(P2->getTemplateParameters()->size()); 5084 if (DeduceTemplateArgumentsByTypeMatch(S, P2->getTemplateParameters(), 5085 T2, T1, Info, Deduced, TDF_None, 5086 /*PartialOrdering=*/true)) 5087 return false; 5088 5089 SmallVector<TemplateArgument, 4> DeducedArgs(Deduced.begin(), 5090 Deduced.end()); 5091 Sema::InstantiatingTemplate Inst(S, Info.getLocation(), P2, DeducedArgs, 5092 Info); 5093 auto *TST1 = T1->castAs<TemplateSpecializationType>(); 5094 if (FinishTemplateArgumentDeduction( 5095 S, P2, /*IsPartialOrdering=*/true, 5096 TemplateArgumentList(TemplateArgumentList::OnStack, 5097 TST1->template_arguments()), 5098 Deduced, Info)) 5099 return false; 5100 5101 return true; 5102} 5103 5104/// Returns the more specialized class template partial specialization 5105/// according to the rules of partial ordering of class template partial 5106/// specializations (C++ [temp.class.order]). 5107/// 5108/// \param PS1 the first class template partial specialization 5109/// 5110/// \param PS2 the second class template partial specialization 5111/// 5112/// \returns the more specialized class template partial specialization. If 5113/// neither partial specialization is more specialized, returns NULL. 5114ClassTemplatePartialSpecializationDecl * 5115Sema::getMoreSpecializedPartialSpecialization( 5116 ClassTemplatePartialSpecializationDecl *PS1, 5117 ClassTemplatePartialSpecializationDecl *PS2, 5118 SourceLocation Loc) { 5119 QualType PT1 = PS1->getInjectedSpecializationType(); 5120 QualType PT2 = PS2->getInjectedSpecializationType(); 5121 5122 TemplateDeductionInfo Info(Loc); 5123 bool Better1 = isAtLeastAsSpecializedAs(*this, PT1, PT2, PS2, Info); 5124 bool Better2 = isAtLeastAsSpecializedAs(*this, PT2, PT1, PS1, Info); 5125 5126 if (Better1 == Better2) 5127 return nullptr; 5128 5129 return Better1 ? PS1 : PS2; 5130} 5131 5132bool Sema::isMoreSpecializedThanPrimary( 5133 ClassTemplatePartialSpecializationDecl *Spec, TemplateDeductionInfo &Info) { 5134 ClassTemplateDecl *Primary = Spec->getSpecializedTemplate(); 5135 QualType PrimaryT = Primary->getInjectedClassNameSpecialization(); 5136 QualType PartialT = Spec->getInjectedSpecializationType(); 5137 if (!isAtLeastAsSpecializedAs(*this, PartialT, PrimaryT, Primary, Info)) 5138 return false; 5139 if (isAtLeastAsSpecializedAs(*this, PrimaryT, PartialT, Spec, Info)) { 5140 Info.clearSFINAEDiagnostic(); 5141 return false; 5142 } 5143 return true; 5144} 5145 5146VarTemplatePartialSpecializationDecl * 5147Sema::getMoreSpecializedPartialSpecialization( 5148 VarTemplatePartialSpecializationDecl *PS1, 5149 VarTemplatePartialSpecializationDecl *PS2, SourceLocation Loc) { 5150 // Pretend the variable template specializations are class template 5151 // specializations and form a fake injected class name type for comparison. 5152 assert(PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() &&((PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate
() && "the partial specializations being compared should specialize"
" the same template.") ? static_cast<void> (0) : __assert_fail
("PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() && \"the partial specializations being compared should specialize\" \" the same template.\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 5154, __PRETTY_FUNCTION__)) 5153 "the partial specializations being compared should specialize"((PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate
() && "the partial specializations being compared should specialize"
" the same template.") ? static_cast<void> (0) : __assert_fail
("PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() && \"the partial specializations being compared should specialize\" \" the same template.\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 5154, __PRETTY_FUNCTION__)) 5154 " the same template.")((PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate
() && "the partial specializations being compared should specialize"
" the same template.") ? static_cast<void> (0) : __assert_fail
("PS1->getSpecializedTemplate() == PS2->getSpecializedTemplate() && \"the partial specializations being compared should specialize\" \" the same template.\""
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 5154, __PRETTY_FUNCTION__)); 5155 TemplateName Name(PS1->getSpecializedTemplate()); 5156 TemplateName CanonTemplate = Context.getCanonicalTemplateName(Name); 5157 QualType PT1 = Context.getTemplateSpecializationType( 5158 CanonTemplate, PS1->getTemplateArgs().asArray()); 5159 QualType PT2 = Context.getTemplateSpecializationType( 5160 CanonTemplate, PS2->getTemplateArgs().asArray()); 5161 5162 TemplateDeductionInfo Info(Loc); 5163 bool Better1 = isAtLeastAsSpecializedAs(*this, PT1, PT2, PS2, Info); 5164 bool Better2 = isAtLeastAsSpecializedAs(*this, PT2, PT1, PS1, Info); 5165 5166 if (Better1 == Better2) 5167 return nullptr; 5168 5169 return Better1 ? PS1 : PS2; 5170} 5171 5172bool Sema::isMoreSpecializedThanPrimary( 5173 VarTemplatePartialSpecializationDecl *Spec, TemplateDeductionInfo &Info) { 5174 TemplateDecl *Primary = Spec->getSpecializedTemplate(); 5175 // FIXME: Cache the injected template arguments rather than recomputing 5176 // them for each partial specialization. 5177 SmallVector<TemplateArgument, 8> PrimaryArgs; 5178 Context.getInjectedTemplateArgs(Primary->getTemplateParameters(), 5179 PrimaryArgs); 5180 5181 TemplateName CanonTemplate = 5182 Context.getCanonicalTemplateName(TemplateName(Primary)); 5183 QualType PrimaryT = Context.getTemplateSpecializationType( 5184 CanonTemplate, PrimaryArgs); 5185 QualType PartialT = Context.getTemplateSpecializationType( 5186 CanonTemplate, Spec->getTemplateArgs().asArray()); 5187 if (!isAtLeastAsSpecializedAs(*this, PartialT, PrimaryT, Primary, Info)) 5188 return false; 5189 if (isAtLeastAsSpecializedAs(*this, PrimaryT, PartialT, Spec, Info)) { 5190 Info.clearSFINAEDiagnostic(); 5191 return false; 5192 } 5193 return true; 5194} 5195 5196bool Sema::isTemplateTemplateParameterAtLeastAsSpecializedAs( 5197 TemplateParameterList *P, TemplateDecl *AArg, SourceLocation Loc) { 5198 // C++1z [temp.arg.template]p4: (DR 150) 5199 // A template template-parameter P is at least as specialized as a 5200 // template template-argument A if, given the following rewrite to two 5201 // function templates... 5202 5203 // Rather than synthesize function templates, we merely perform the 5204 // equivalent partial ordering by performing deduction directly on 5205 // the template parameter lists of the template template parameters. 5206 // 5207 // Given an invented class template X with the template parameter list of 5208 // A (including default arguments): 5209 TemplateName X = Context.getCanonicalTemplateName(TemplateName(AArg)); 5210 TemplateParameterList *A = AArg->getTemplateParameters(); 5211 5212 // - Each function template has a single function parameter whose type is 5213 // a specialization of X with template arguments corresponding to the 5214 // template parameters from the respective function template 5215 SmallVector<TemplateArgument, 8> AArgs; 5216 Context.getInjectedTemplateArgs(A, AArgs); 5217 5218 // Check P's arguments against A's parameter list. This will fill in default 5219 // template arguments as needed. AArgs are already correct by construction. 5220 // We can't just use CheckTemplateIdType because that will expand alias 5221 // templates. 5222 SmallVector<TemplateArgument, 4> PArgs; 5223 { 5224 SFINAETrap Trap(*this); 5225 5226 Context.getInjectedTemplateArgs(P, PArgs); 5227 TemplateArgumentListInfo PArgList(P->getLAngleLoc(), P->getRAngleLoc()); 5228 for (unsigned I = 0, N = P->size(); I != N; ++I) { 5229 // Unwrap packs that getInjectedTemplateArgs wrapped around pack 5230 // expansions, to form an "as written" argument list. 5231 TemplateArgument Arg = PArgs[I]; 5232 if (Arg.getKind() == TemplateArgument::Pack) { 5233 assert(Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion())((Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion
()) ? static_cast<void> (0) : __assert_fail ("Arg.pack_size() == 1 && Arg.pack_begin()->isPackExpansion()"
, "/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/lib/Sema/SemaTemplateDeduction.cpp"
, 5233, __PRETTY_FUNCTION__)); 5234 Arg = *Arg.pack_begin(); 5235 } 5236 PArgList.addArgument(getTrivialTemplateArgumentLoc( 5237 Arg, QualType(), P->getParam(I)->getLocation())); 5238 } 5239 PArgs.clear(); 5240 5241 // C++1z [temp.arg.template]p3: 5242 // If the rewrite produces an invalid type, then P is not at least as 5243 // specialized as A. 5244 if (CheckTemplateArgumentList(AArg, Loc, PArgList, false, PArgs) || 5245 Trap.hasErrorOccurred()) 5246 return false; 5247 } 5248 5249 QualType AType = Context.getTemplateSpecializationType(X, AArgs); 5250 QualType PType = Context.getTemplateSpecializationType(X, PArgs); 5251 5252 // ... the function template corresponding to P is at least as specialized 5253 // as the function template corresponding to A according to the partial 5254 // ordering rules for function templates. 5255 TemplateDeductionInfo Info(Loc, A->getDepth()); 5256 return isAtLeastAsSpecializedAs(*this, PType, AType, AArg, Info); 5257} 5258 5259/// Mark the template parameters that are used by the given 5260/// expression. 5261static void 5262MarkUsedTemplateParameters(ASTContext &Ctx, 5263 const Expr *E, 5264 bool OnlyDeduced, 5265 unsigned Depth, 5266 llvm::SmallBitVector &Used) { 5267 // We can deduce from a pack expansion. 5268 if (const PackExpansionExpr *Expansion = dyn_cast<PackExpansionExpr>(E)) 5269 E = Expansion->getPattern(); 5270 5271 // Skip through any implicit casts we added while type-checking, and any 5272 // substitutions performed by template alias expansion. 5273 while (true) { 5274 if (const ImplicitCastExpr *ICE = dyn_cast<ImplicitCastExpr>(E)) 5275 E = ICE->getSubExpr(); 5276 else if (const ConstantExpr *CE = dyn_cast<ConstantExpr>(E)) 5277 E = CE->getSubExpr(); 5278 else if (const SubstNonTypeTemplateParmExpr *Subst = 5279 dyn_cast<SubstNonTypeTemplateParmExpr>(E)) 5280 E = Subst->getReplacement(); 5281 else 5282 break; 5283 } 5284 5285 // FIXME: if !OnlyDeduced, we have to walk the whole subexpression to 5286 // find other occurrences of template parameters. 5287 const DeclRefExpr *DRE = dyn_cast<DeclRefExpr>(E); 5288 if (!DRE) 5289 return; 5290 5291 const NonTypeTemplateParmDecl *NTTP 5292 = dyn_cast<NonTypeTemplateParmDecl>(DRE->getDecl()); 5293 if (!NTTP) 5294 return; 5295 5296 if (NTTP->getDepth() == Depth) 5297 Used[NTTP->getIndex()] = true; 5298 5299 // In C++17 mode, additional arguments may be deduced from the type of a 5300 // non-type argument. 5301 if (Ctx.getLangOpts().CPlusPlus17) 5302 MarkUsedTemplateParameters(Ctx, NTTP->getType(), OnlyDeduced, Depth, Used); 5303} 5304 5305/// Mark the template parameters that are used by the given 5306/// nested name specifier. 5307static void 5308MarkUsedTemplateParameters(ASTContext &Ctx, 5309 NestedNameSpecifier *NNS, 5310 bool OnlyDeduced, 5311 unsigned Depth, 5312 llvm::SmallBitVector &Used) { 5313 if (!NNS) 5314 return; 5315 5316 MarkUsedTemplateParameters(Ctx, NNS->getPrefix(), OnlyDeduced, Depth, 5317 Used); 5318 MarkUsedTemplateParameters(Ctx, QualType(NNS->getAsType(), 0), 5319 OnlyDeduced, Depth, Used); 5320} 5321 5322/// Mark the template parameters that are used by the given 5323/// template name. 5324static void 5325MarkUsedTemplateParameters(ASTContext &Ctx, 5326 TemplateName Name, 5327 bool OnlyDeduced, 5328 unsigned Depth, 5329 llvm::SmallBitVector &Used) { 5330 if (TemplateDecl *Template = Name.getAsTemplateDecl()) { 5331 if (TemplateTemplateParmDecl *TTP 5332 = dyn_cast<TemplateTemplateParmDecl>(Template)) { 5333 if (TTP->getDepth() == Depth) 5334 Used[TTP->getIndex()] = true; 5335 } 5336 return; 5337 } 5338 5339 if (QualifiedTemplateName *QTN = Name.getAsQualifiedTemplateName()) 5340 MarkUsedTemplateParameters(Ctx, QTN->getQualifier(), OnlyDeduced, 5341 Depth, Used); 5342 if (DependentTemplateName *DTN = Name.getAsDependentTemplateName()) 5343 MarkUsedTemplateParameters(Ctx, DTN->getQualifier(), OnlyDeduced, 5344 Depth, Used); 5345} 5346 5347/// Mark the template parameters that are used by the given 5348/// type. 5349static void 5350MarkUsedTemplateParameters(ASTContext &Ctx, QualType T, 5351 bool OnlyDeduced, 5352 unsigned Depth, 5353 llvm::SmallBitVector &Used) { 5354 if (T.isNull()) 5355 return; 5356 5357 // Non-dependent types have nothing deducible 5358 if (!T->isDependentType()) 5359 return; 5360 5361 T = Ctx.getCanonicalType(T); 5362 switch (T->getTypeClass()) { 5363 case Type::Pointer: 5364 MarkUsedTemplateParameters(Ctx, 5365 cast<PointerType>(T)->getPointeeType(), 5366 OnlyDeduced, 5367 Depth, 5368 Used); 5369 break; 5370 5371 case Type::BlockPointer: 5372 MarkUsedTemplateParameters(Ctx, 5373 cast<BlockPointerType>(T)->getPointeeType(), 5374 OnlyDeduced, 5375 Depth, 5376 Used); 5377 break; 5378 5379 case Type::LValueReference: 5380 case Type::RValueReference: 5381 MarkUsedTemplateParameters(Ctx, 5382 cast<ReferenceType>(T)->getPointeeType(), 5383 OnlyDeduced, 5384 Depth, 5385 Used); 5386 break; 5387 5388 case Type::MemberPointer: { 5389 const MemberPointerType *MemPtr = cast<MemberPointerType>(T.getTypePtr()); 5390 MarkUsedTemplateParameters(Ctx, MemPtr->getPointeeType(), OnlyDeduced, 5391 Depth, Used); 5392 MarkUsedTemplateParameters(Ctx, QualType(MemPtr->getClass(), 0), 5393 OnlyDeduced, Depth, Used); 5394 break; 5395 } 5396 5397 case Type::DependentSizedArray: 5398 MarkUsedTemplateParameters(Ctx, 5399 cast<DependentSizedArrayType>(T)->getSizeExpr(), 5400 OnlyDeduced, Depth, Used); 5401 // Fall through to check the element type 5402 LLVM_FALLTHROUGH[[gnu::fallthrough]]; 5403 5404 case Type::ConstantArray: 5405 case Type::IncompleteArray: 5406 MarkUsedTemplateParameters(Ctx, 5407 cast<ArrayType>(T)->getElementType(), 5408 OnlyDeduced, Depth, Used); 5409 break; 5410 5411 case Type::Vector: 5412 case Type::ExtVector: 5413 MarkUsedTemplateParameters(Ctx, 5414 cast<VectorType>(T)->getElementType(), 5415 OnlyDeduced, Depth, Used); 5416 break; 5417 5418 case Type::DependentVector: { 5419 const auto *VecType = cast<DependentVectorType>(T); 5420 MarkUsedTemplateParameters(Ctx, VecType->getElementType(), OnlyDeduced, 5421 Depth, Used); 5422 MarkUsedTemplateParameters(Ctx, VecType->getSizeExpr(), OnlyDeduced, Depth, 5423 Used); 5424 break; 5425 } 5426 case Type::DependentSizedExtVector: { 5427 const DependentSizedExtVectorType *VecType 5428 = cast<DependentSizedExtVectorType>(T); 5429 MarkUsedTemplateParameters(Ctx, VecType->getElementType(), OnlyDeduced, 5430 Depth, Used); 5431 MarkUsedTemplateParameters(Ctx, VecType->getSizeExpr(), OnlyDeduced, 5432 Depth, Used); 5433 break; 5434 } 5435 5436 case Type::DependentAddressSpace: { 5437 const DependentAddressSpaceType *DependentASType = 5438 cast<DependentAddressSpaceType>(T); 5439 MarkUsedTemplateParameters(Ctx, DependentASType->getPointeeType(), 5440 OnlyDeduced, Depth, Used); 5441 MarkUsedTemplateParameters(Ctx, 5442 DependentASType->getAddrSpaceExpr(), 5443 OnlyDeduced, Depth, Used); 5444 break; 5445 } 5446 5447 case Type::FunctionProto: { 5448 const FunctionProtoType *Proto = cast<FunctionProtoType>(T); 5449 MarkUsedTemplateParameters(Ctx, Proto->getReturnType(), OnlyDeduced, Depth, 5450 Used); 5451 for (unsigned I = 0, N = Proto->getNumParams(); I != N; ++I) { 5452 // C++17 [temp.deduct.type]p5: 5453 // The non-deduced contexts are: [...] 5454 // -- A function parameter pack that does not occur at the end of the 5455 // parameter-declaration-list. 5456 if (!OnlyDeduced || I + 1 == N || 5457 !Proto->getParamType(I)->getAs<PackExpansionType>()) { 5458 MarkUsedTemplateParameters(Ctx, Proto->getParamType(I), OnlyDeduced, 5459 Depth, Used); 5460 } else { 5461 // FIXME: C++17 [temp.deduct.call]p1: 5462 // When a function parameter pack appears in a non-deduced context, 5463 // the type of that pack is never deduced. 5464 // 5465 // We should also track a set of "never deduced" parameters, and 5466 // subtract that from the list of deduced parameters after marking. 5467 } 5468 } 5469 if (auto *E = Proto->getNoexceptExpr()) 5470 MarkUsedTemplateParameters(Ctx, E, OnlyDeduced, Depth, Used); 5471 break; 5472 } 5473 5474 case Type::TemplateTypeParm: { 5475 const TemplateTypeParmType *TTP = cast<TemplateTypeParmType>(T); 5476 if (TTP->getDepth() == Depth) 5477 Used[TTP->getIndex()] = true; 5478 break; 5479 } 5480 5481 case Type::SubstTemplateTypeParmPack: { 5482 const SubstTemplateTypeParmPackType *Subst 5483 = cast<SubstTemplateTypeParmPackType>(T); 5484 MarkUsedTemplateParameters(Ctx, 5485 QualType(Subst->getReplacedParameter(), 0), 5486 OnlyDeduced, Depth, Used); 5487 MarkUsedTemplateParameters(Ctx, Subst->getArgumentPack(), 5488 OnlyDeduced, Depth, Used); 5489 break; 5490 } 5491 5492 case Type::InjectedClassName: 5493 T = cast<InjectedClassNameType>(T)->getInjectedSpecializationType(); 5494 LLVM_FALLTHROUGH[[gnu::fallthrough]]; 5495 5496 case Type::TemplateSpecialization: { 5497 const TemplateSpecializationType *Spec 5498 = cast<TemplateSpecializationType>(T); 5499 MarkUsedTemplateParameters(Ctx, Spec->getTemplateName(), OnlyDeduced, 5500 Depth, Used); 5501 5502 // C++0x [temp.deduct.type]p9: 5503 // If the template argument list of P contains a pack expansion that is 5504 // not the last template argument, the entire template argument list is a 5505 // non-deduced context. 5506 if (OnlyDeduced && 5507 hasPackExpansionBeforeEnd(Spec->template_arguments())) 5508 break; 5509 5510 for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I) 5511 MarkUsedTemplateParameters(Ctx, Spec->getArg(I), OnlyDeduced, Depth, 5512 Used); 5513 break; 5514 } 5515 5516 case Type::Complex: 5517 if (!OnlyDeduced) 5518 MarkUsedTemplateParameters(Ctx, 5519 cast<ComplexType>(T)->getElementType(), 5520 OnlyDeduced, Depth, Used); 5521 break; 5522 5523 case Type::Atomic: 5524 if (!OnlyDeduced) 5525 MarkUsedTemplateParameters(Ctx, 5526 cast<AtomicType>(T)->getValueType(), 5527 OnlyDeduced, Depth, Used); 5528 break; 5529 5530 case Type::DependentName: 5531 if (!OnlyDeduced) 5532 MarkUsedTemplateParameters(Ctx, 5533 cast<DependentNameType>(T)->getQualifier(), 5534 OnlyDeduced, Depth, Used); 5535 break; 5536 5537 case Type::DependentTemplateSpecialization: { 5538 // C++14 [temp.deduct.type]p5: 5539 // The non-deduced contexts are: 5540 // -- The nested-name-specifier of a type that was specified using a 5541 // qualified-id 5542 // 5543 // C++14 [temp.deduct.type]p6: 5544 // When a type name is specified in a way that includes a non-deduced 5545 // context, all of the types that comprise that type name are also 5546 // non-deduced. 5547 if (OnlyDeduced) 5548 break; 5549 5550 const DependentTemplateSpecializationType *Spec 5551 = cast<DependentTemplateSpecializationType>(T); 5552 5553 MarkUsedTemplateParameters(Ctx, Spec->getQualifier(), 5554 OnlyDeduced, Depth, Used); 5555 5556 for (unsigned I = 0, N = Spec->getNumArgs(); I != N; ++I) 5557 MarkUsedTemplateParameters(Ctx, Spec->getArg(I), OnlyDeduced, Depth, 5558 Used); 5559 break; 5560 } 5561 5562 case Type::TypeOf: 5563 if (!OnlyDeduced) 5564 MarkUsedTemplateParameters(Ctx, 5565 cast<TypeOfType>(T)->getUnderlyingType(), 5566 OnlyDeduced, Depth, Used); 5567 break; 5568 5569 case Type::TypeOfExpr: 5570 if (!OnlyDeduced) 5571 MarkUsedTemplateParameters(Ctx, 5572 cast<TypeOfExprType>(T)->getUnderlyingExpr(), 5573 OnlyDeduced, Depth, Used); 5574 break; 5575 5576 case Type::Decltype: 5577 if (!OnlyDeduced) 5578 MarkUsedTemplateParameters(Ctx, 5579 cast<DecltypeType>(T)->getUnderlyingExpr(), 5580 OnlyDeduced, Depth, Used); 5581 break; 5582 5583 case Type::UnaryTransform: 5584 if (!OnlyDeduced) 5585 MarkUsedTemplateParameters(Ctx, 5586 cast<UnaryTransformType>(T)->getUnderlyingType(), 5587 OnlyDeduced, Depth, Used); 5588 break; 5589 5590 case Type::PackExpansion: 5591 MarkUsedTemplateParameters(Ctx, 5592 cast<PackExpansionType>(T)->getPattern(), 5593 OnlyDeduced, Depth, Used); 5594 break; 5595 5596 case Type::Auto: 5597 case Type::DeducedTemplateSpecialization: 5598 MarkUsedTemplateParameters(Ctx, 5599 cast<DeducedType>(T)->getDeducedType(), 5600 OnlyDeduced, Depth, Used); 5601 break; 5602 5603 // None of these types have any template parameters in them. 5604 case Type::Builtin: 5605 case Type::VariableArray: 5606 case Type::FunctionNoProto: 5607 case Type::Record: 5608 case Type::Enum: 5609 case Type::ObjCInterface: 5610 case Type::ObjCObject: 5611 case Type::ObjCObjectPointer: 5612 case Type::UnresolvedUsing: 5613 case Type::Pipe: 5614#define TYPE(Class, Base) 5615#define ABSTRACT_TYPE(Class, Base) 5616#define DEPENDENT_TYPE(Class, Base) 5617#define NON_CANONICAL_TYPE(Class, Base) case Type::Class: 5618#include "clang/AST/TypeNodes.inc" 5619 break; 5620 } 5621} 5622 5623/// Mark the template parameters that are used by this 5624/// template argument. 5625static void 5626MarkUsedTemplateParameters(ASTContext &Ctx, 5627 const TemplateArgument &TemplateArg, 5628 bool OnlyDeduced, 5629 unsigned Depth, 5630 llvm::SmallBitVector &Used) { 5631 switch (TemplateArg.getKind()) { 5632 case TemplateArgument::Null: 5633 case TemplateArgument::Integral: 5634 case TemplateArgument::Declaration: 5635 break; 5636 5637 case TemplateArgument::NullPtr: 5638 MarkUsedTemplateParameters(Ctx, TemplateArg.getNullPtrType(), OnlyDeduced, 5639 Depth, Used); 5640 break; 5641 5642 case TemplateArgument::Type: 5643 MarkUsedTemplateParameters(Ctx, TemplateArg.getAsType(), OnlyDeduced, 5644 Depth, Used); 5645 break; 5646 5647 case TemplateArgument::Template: 5648 case TemplateArgument::TemplateExpansion: 5649 MarkUsedTemplateParameters(Ctx, 5650 TemplateArg.getAsTemplateOrTemplatePattern(), 5651 OnlyDeduced, Depth, Used); 5652 break; 5653 5654 case TemplateArgument::Expression: 5655 MarkUsedTemplateParameters(Ctx, TemplateArg.getAsExpr(), OnlyDeduced, 5656 Depth, Used); 5657 break; 5658 5659 case TemplateArgument::Pack: 5660 for (const auto &P : TemplateArg.pack_elements()) 5661 MarkUsedTemplateParameters(Ctx, P, OnlyDeduced, Depth, Used); 5662 break; 5663 } 5664} 5665 5666/// Mark which template parameters can be deduced from a given 5667/// template argument list. 5668/// 5669/// \param TemplateArgs the template argument list from which template 5670/// parameters will be deduced. 5671/// 5672/// \param Used a bit vector whose elements will be set to \c true 5673/// to indicate when the corresponding template parameter will be 5674/// deduced. 5675void 5676Sema::MarkUsedTemplateParameters(const TemplateArgumentList &TemplateArgs, 5677 bool OnlyDeduced, unsigned Depth, 5678 llvm::SmallBitVector &Used) { 5679 // C++0x [temp.deduct.type]p9: 5680 // If the template argument list of P contains a pack expansion that is not 5681 // the last template argument, the entire template argument list is a 5682 // non-deduced context. 5683 if (OnlyDeduced && 5684 hasPackExpansionBeforeEnd(TemplateArgs.asArray())) 5685 return; 5686 5687 for (unsigned I = 0, N = TemplateArgs.size(); I != N; ++I) 5688 ::MarkUsedTemplateParameters(Context, TemplateArgs[I], OnlyDeduced, 5689 Depth, Used); 5690} 5691 5692/// Marks all of the template parameters that will be deduced by a 5693/// call to the given function template. 5694void Sema::MarkDeducedTemplateParameters( 5695 ASTContext &Ctx, const FunctionTemplateDecl *FunctionTemplate, 5696 llvm::SmallBitVector &Deduced) { 5697 TemplateParameterList *TemplateParams 5698 = FunctionTemplate->getTemplateParameters(); 5699 Deduced.clear(); 5700 Deduced.resize(TemplateParams->size()); 5701 5702 FunctionDecl *Function = FunctionTemplate->getTemplatedDecl(); 5703 for (unsigned I = 0, N = Function->getNumParams(); I != N; ++I) 5704 ::MarkUsedTemplateParameters(Ctx, Function->getParamDecl(I)->getType(), 5705 true, TemplateParams->getDepth(), Deduced); 5706} 5707 5708bool hasDeducibleTemplateParameters(Sema &S, 5709 FunctionTemplateDecl *FunctionTemplate, 5710 QualType T) { 5711 if (!T->isDependentType()) 5712 return false; 5713 5714 TemplateParameterList *TemplateParams 5715 = FunctionTemplate->getTemplateParameters(); 5716 llvm::SmallBitVector Deduced(TemplateParams->size()); 5717 ::MarkUsedTemplateParameters(S.Context, T, true, TemplateParams->getDepth(), 5718 Deduced); 5719 5720 return Deduced.any(); 5721}

←

/build/llvm-toolchain-snapshot-10~svn374877/tools/clang/include/clang/AST/Type.h

→

1	//===- Type.h - C Language Family Type Representation ------------ C++ --===//
2	//
3	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4	// See https://llvm.org/LICENSE.txt for license information.
5	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6	//
7	//===----------------------------------------------------------------------===//
8	//
9	/// \file
10	/// C Language Family Type Representation
11	///
12	/// This file defines the clang::Type interface and subclasses, used to
13	/// represent types for languages in the C family.
14	//
15	//===----------------------------------------------------------------------===//
16
17	#ifndef LLVM_CLANG_AST_TYPE_H
18	#define LLVM_CLANG_AST_TYPE_H
19
20	#include "clang/AST/NestedNameSpecifier.h"
21	#include "clang/AST/TemplateName.h"
22	#include "clang/Basic/AddressSpaces.h"
23	#include "clang/Basic/AttrKinds.h"
24	#include "clang/Basic/Diagnostic.h"
25	#include "clang/Basic/ExceptionSpecificationType.h"
26	#include "clang/Basic/LLVM.h"
27	#include "clang/Basic/Linkage.h"
28	#include "clang/Basic/PartialDiagnostic.h"
29	#include "clang/Basic/SourceLocation.h"
30	#include "clang/Basic/Specifiers.h"
31	#include "clang/Basic/Visibility.h"
32	#include "llvm/ADT/APInt.h"
33	#include "llvm/ADT/APSInt.h"
34	#include "llvm/ADT/ArrayRef.h"
35	#include "llvm/ADT/FoldingSet.h"
36	#include "llvm/ADT/None.h"
37	#include "llvm/ADT/Optional.h"
38	#include "llvm/ADT/PointerIntPair.h"
39	#include "llvm/ADT/PointerUnion.h"
40	#include "llvm/ADT/StringRef.h"
41	#include "llvm/ADT/Twine.h"
42	#include "llvm/ADT/iterator_range.h"
43	#include "llvm/Support/Casting.h"
44	#include "llvm/Support/Compiler.h"
45	#include "llvm/Support/ErrorHandling.h"
46	#include "llvm/Support/PointerLikeTypeTraits.h"
47	#include "llvm/Support/type_traits.h"
48	#include "llvm/Support/TrailingObjects.h"
49	#include <cassert>
50	#include <cstddef>
51	#include <cstdint>
52	#include <cstring>
53	#include <string>
54	#include <type_traits>
55	#include <utility>
56
57	namespace clang {
58
59	class ExtQuals;
60	class QualType;
61	class TagDecl;
62	class Type;
63
64	enum {
65	TypeAlignmentInBits = 4,
66	TypeAlignment = 1 << TypeAlignmentInBits
67	};
68
69	} // namespace clang
70
71	namespace llvm {
72
73	template <typename T>
74	struct PointerLikeTypeTraits;
75	template<>
76	struct PointerLikeTypeTraits< ::clang::Type*> {
77	static inline void getAsVoidPointer(::clang::Type P) { return P; }
78
79	static inline ::clang::Type getFromVoidPointer(void P) {
80	return static_cast< ::clang::Type*>(P);
81	}
82
83	enum { NumLowBitsAvailable = clang::TypeAlignmentInBits };
84	};
85
86	template<>
87	struct PointerLikeTypeTraits< ::clang::ExtQuals*> {
88	static inline void getAsVoidPointer(::clang::ExtQuals P) { return P; }
89
90	static inline ::clang::ExtQuals getFromVoidPointer(void P) {
91	return static_cast< ::clang::ExtQuals*>(P);
92	}
93
94	enum { NumLowBitsAvailable = clang::TypeAlignmentInBits };
95	};
96
97	} // namespace llvm
98
99	namespace clang {
100
101	class ASTContext;
102	template <typename> class CanQual;
103	class CXXRecordDecl;
104	class DeclContext;
105	class EnumDecl;
106	class Expr;
107	class ExtQualsTypeCommonBase;
108	class FunctionDecl;
109	class IdentifierInfo;
110	class NamedDecl;
111	class ObjCInterfaceDecl;
112	class ObjCProtocolDecl;
113	class ObjCTypeParamDecl;
114	struct PrintingPolicy;
115	class RecordDecl;
116	class Stmt;
117	class TagDecl;
118	class TemplateArgument;
119	class TemplateArgumentListInfo;
120	class TemplateArgumentLoc;
121	class TemplateTypeParmDecl;
122	class TypedefNameDecl;
123	class UnresolvedUsingTypenameDecl;
124
125	using CanQualType = CanQual<Type>;
126
127	// Provide forward declarations for all of the *Type classes.
128	#define TYPE(Class, Base) class Class##Type;
129	#include "clang/AST/TypeNodes.inc"
130
131	/// The collection of all-type qualifiers we support.
132	/// Clang supports five independent qualifiers:
133	/// * C99: const, volatile, and restrict
134	/// * MS: __unaligned
135	/// * Embedded C (TR18037): address spaces
136	/// * Objective C: the GC attributes (none, weak, or strong)
137	class Qualifiers {
138	public:
139	enum TQ { // NOTE: These flags must be kept in sync with DeclSpec::TQ.
140	Const = 0x1,
141	Restrict = 0x2,
142	Volatile = 0x4,
143	CVRMask = Const \| Volatile \| Restrict
144	};
145
146	enum GC {
147	GCNone = 0,
148	Weak,
149	Strong
150	};
151
152	enum ObjCLifetime {
153	/// There is no lifetime qualification on this type.
154	OCL_None,
155
156	/// This object can be modified without requiring retains or
157	/// releases.
158	OCL_ExplicitNone,
159
160	/// Assigning into this object requires the old value to be
161	/// released and the new value to be retained. The timing of the
162	/// release of the old value is inexact: it may be moved to
163	/// immediately after the last known point where the value is
164	/// live.
165	OCL_Strong,
166
167	/// Reading or writing from this object requires a barrier call.
168	OCL_Weak,
169
170	/// Assigning into this object requires a lifetime extension.
171	OCL_Autoreleasing
172	};
173
174	enum {
175	/// The maximum supported address space number.
176	/// 23 bits should be enough for anyone.
177	MaxAddressSpace = 0x7fffffu,
178
179	/// The width of the "fast" qualifier mask.
180	FastWidth = 3,
181
182	/// The fast qualifier mask.
183	FastMask = (1 << FastWidth) - 1
184	};
185
186	/// Returns the common set of qualifiers while removing them from
187	/// the given sets.
188	static Qualifiers removeCommonQualifiers(Qualifiers &L, Qualifiers &R) {
189	// If both are only CVR-qualified, bit operations are sufficient.
190	if (!(L.Mask & ~CVRMask) && !(R.Mask & ~CVRMask)) {
191	Qualifiers Q;
192	Q.Mask = L.Mask & R.Mask;
193	L.Mask &= ~Q.Mask;
194	R.Mask &= ~Q.Mask;
195	return Q;
196	}
197
198	Qualifiers Q;