Bug Summary

File:tools/lld/lib/ReaderWriter/MachO/TLVPass.cpp
Warning:line 124, column 5
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -disable-llvm-verifier -discard-value-names -main-file-name TLVPass.cpp -analyzer-store=region -analyzer-opt-analyze-nested-blocks -analyzer-eagerly-assume -analyzer-checker=core -analyzer-checker=apiModeling -analyzer-checker=unix -analyzer-checker=deadcode -analyzer-checker=cplusplus -analyzer-checker=security.insecureAPI.UncheckedReturn -analyzer-checker=security.insecureAPI.getpw -analyzer-checker=security.insecureAPI.gets -analyzer-checker=security.insecureAPI.mktemp -analyzer-checker=security.insecureAPI.mkstemp -analyzer-checker=security.insecureAPI.vfork -analyzer-checker=nullability.NullPassedToNonnull -analyzer-checker=nullability.NullReturnedFromNonnull -analyzer-output plist -w -mrelocation-model pic -pic-level 2 -mthread-model posix -fmath-errno -masm-verbose -mconstructor-aliases -munwind-tables -fuse-init-array -target-cpu x86-64 -dwarf-column-info -debugger-tuning=gdb -momit-leaf-frame-pointer -ffunction-sections -fdata-sections -resource-dir /usr/lib/llvm-7/lib/clang/7.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-7~svn329677/build-llvm/tools/lld/lib/ReaderWriter/MachO -I /build/llvm-toolchain-snapshot-7~svn329677/tools/lld/lib/ReaderWriter/MachO -I /build/llvm-toolchain-snapshot-7~svn329677/tools/lld/include -I /build/llvm-toolchain-snapshot-7~svn329677/build-llvm/tools/lld/include -I /build/llvm-toolchain-snapshot-7~svn329677/build-llvm/include -I /build/llvm-toolchain-snapshot-7~svn329677/include -I /build/llvm-toolchain-snapshot-7~svn329677/tools/lld/lib/ReaderWriter/MachO/. -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/c++/7.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/x86_64-linux-gnu/c++/7.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/x86_64-linux-gnu/c++/7.3.0 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/7.3.0/../../../../include/c++/7.3.0/backward -internal-isystem /usr/include/clang/7.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-7/lib/clang/7.0.0/include -internal-externc-isystem /usr/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++11 -fdeprecated-macro -fdebug-compilation-dir /build/llvm-toolchain-snapshot-7~svn329677/build-llvm/tools/lld/lib/ReaderWriter/MachO -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-checker optin.performance.Padding -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-04-11-031539-24776-1 -x c++ /build/llvm-toolchain-snapshot-7~svn329677/tools/lld/lib/ReaderWriter/MachO/TLVPass.cpp
1//===- lib/ReaderWriter/MachO/TLVPass.cpp -----------------------*- C++ -*-===//
2//
3// The LLVM Linker
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9///
10/// \file
11/// This linker pass transforms all TLV references to real references.
12///
13//===----------------------------------------------------------------------===//
14
15#include "ArchHandler.h"
16#include "File.h"
17#include "MachOPasses.h"
18#include "lld/Core/Simple.h"
19#include "llvm/ADT/STLExtras.h"
20#include "llvm/Support/Debug.h"
21
22namespace lld {
23namespace mach_o {
24
25//
26// TLVP Entry Atom created by the TLV pass.
27//
28class TLVPEntryAtom : public SimpleDefinedAtom {
29public:
30 TLVPEntryAtom(const File &file, bool is64, StringRef name)
31 : SimpleDefinedAtom(file), _is64(is64), _name(name) {}
32
33 ~TLVPEntryAtom() override = default;
34
35 ContentType contentType() const override {
36 return DefinedAtom::typeTLVInitializerPtr;
37 }
38
39 Alignment alignment() const override {
40 return _is64 ? 8 : 4;
41 }
42
43 uint64_t size() const override {
44 return _is64 ? 8 : 4;
45 }
46
47 ContentPermissions permissions() const override {
48 return DefinedAtom::permRW_;
49 }
50
51 ArrayRef<uint8_t> rawContent() const override {
52 static const uint8_t zeros[] =
53 { 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00 };
54 return llvm::makeArrayRef(zeros, size());
55 }
56
57 StringRef slotName() const {
58 return _name;
59 }
60
61private:
62 const bool _is64;
63 StringRef _name;
64};
65
66class TLVPass : public Pass {
67public:
68 TLVPass(const MachOLinkingContext &context)
69 : _ctx(context), _archHandler(_ctx.archHandler()),
70 _file(*_ctx.make_file<MachOFile>("<mach-o TLV pass>")) {
71 _file.setOrdinal(_ctx.getNextOrdinalAndIncrement());
72 }
73
74private:
75 llvm::Error perform(SimpleFile &mergedFile) override {
76 bool allowTLV = _ctx.minOS("10.7", "1.0");
77
78 for (const DefinedAtom *atom : mergedFile.defined()) {
79 for (const Reference *ref : *atom) {
80 if (!_archHandler.isTLVAccess(*ref))
1
Assuming the condition is false
2
Taking false branch
81 continue;
82
83 if (!allowTLV)
3
Assuming 'allowTLV' is not equal to 0
4
Taking false branch
84 return llvm::make_error<GenericError>(
85 "targeted OS version does not support use of thread local "
86 "variables in " + atom->name() + " for architecture " +
87 _ctx.archName());
88
89 const Atom *target = ref->target();
90 assert(target != nullptr)(static_cast <bool> (target != nullptr) ? void (0) : __assert_fail
("target != nullptr", "/build/llvm-toolchain-snapshot-7~svn329677/tools/lld/lib/ReaderWriter/MachO/TLVPass.cpp"
, 90, __extension__ __PRETTY_FUNCTION__))
;
91
92 const DefinedAtom *tlvpEntry = makeTLVPEntry(target);
5
Calling 'TLVPass::makeTLVPEntry'
93 const_cast<Reference*>(ref)->setTarget(tlvpEntry);
94 _archHandler.updateReferenceToTLV(ref);
95 }
96 }
97
98 std::vector<const TLVPEntryAtom*> entries;
99 entries.reserve(_targetToTLVP.size());
100 for (auto &it : _targetToTLVP)
101 entries.push_back(it.second);
102 std::sort(entries.begin(), entries.end(),
103 [](const TLVPEntryAtom *lhs, const TLVPEntryAtom *rhs) {
104 return (lhs->slotName().compare(rhs->slotName()) < 0);
105 });
106
107 for (const TLVPEntryAtom *slot : entries)
108 mergedFile.addAtom(*slot);
109
110 return llvm::Error::success();
111 }
112
113 const DefinedAtom *makeTLVPEntry(const Atom *target) {
114 auto pos = _targetToTLVP.find(target);
115
116 if (pos != _targetToTLVP.end())
6
Assuming the condition is false
7
Taking false branch
117 return pos->second;
118
119 auto *tlvpEntry = new (_file.allocator())
8
'tlvpEntry' initialized to a null pointer value
120 TLVPEntryAtom(_file, _ctx.is64Bit(), target->name());
121 _targetToTLVP[target] = tlvpEntry;
122 const ArchHandler::ReferenceInfo &nlInfo =
123 _archHandler.stubInfo().nonLazyPointerReferenceToBinder;
124 tlvpEntry->addReference(Reference::KindNamespace::mach_o, nlInfo.arch,
9
Called C++ object pointer is null
125 nlInfo.kind, 0, target, 0);
126 return tlvpEntry;
127 }
128
129 const MachOLinkingContext &_ctx;
130 mach_o::ArchHandler &_archHandler;
131 MachOFile &_file;
132 llvm::DenseMap<const Atom*, const TLVPEntryAtom*> _targetToTLVP;
133};
134
135void addTLVPass(PassManager &pm, const MachOLinkingContext &ctx) {
136 assert(ctx.needsTLVPass())(static_cast <bool> (ctx.needsTLVPass()) ? void (0) : __assert_fail
("ctx.needsTLVPass()", "/build/llvm-toolchain-snapshot-7~svn329677/tools/lld/lib/ReaderWriter/MachO/TLVPass.cpp"
, 136, __extension__ __PRETTY_FUNCTION__))
;
137 pm.add(llvm::make_unique<TLVPass>(ctx));
138}
139
140} // end namesapce mach_o
141} // end namesapce lld