Bug Summary

File:llvm/tools/llvm-libtool-darwin/llvm-libtool-darwin.cpp
Warning:line 292, column 40
Called C++ object pointer is null

Annotated Source Code

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clang -cc1 -cc1 -triple x86_64-pc-linux-gnu -analyze -disable-free -clear-ast-before-backend -disable-llvm-verifier -discard-value-names -main-file-name llvm-libtool-darwin.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 -setup-static-analyzer -analyzer-config-compatibility-mode=true -mrelocation-model pic -pic-level 2 -mframe-pointer=none -fmath-errno -ffp-contract=on -fno-rounding-math -mconstructor-aliases -funwind-tables=2 -target-cpu x86-64 -tune-cpu generic -debugger-tuning=gdb -ffunction-sections -fdata-sections -fcoverage-compilation-dir=/build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/build-llvm/tools/clang/stage2-bins -resource-dir /usr/lib/llvm-14/lib/clang/14.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I tools/llvm-libtool-darwin -I /build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/llvm/tools/llvm-libtool-darwin -I include -I /build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/llvm/include -D _FORTIFY_SOURCE=2 -D NDEBUG -U NDEBUG -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/x86_64-linux-gnu/c++/10 -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../include/c++/10/backward -internal-isystem /usr/lib/llvm-14/lib/clang/14.0.0/include -internal-isystem /usr/local/include -internal-isystem /usr/lib/gcc/x86_64-linux-gnu/10/../../../../x86_64-linux-gnu/include -internal-externc-isystem /usr/include/x86_64-linux-gnu -internal-externc-isystem /include -internal-externc-isystem /usr/include -fmacro-prefix-map=/build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fmacro-prefix-map=/build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/= -fcoverage-prefix-map=/build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fcoverage-prefix-map=/build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/= -O3 -Wno-unused-command-line-argument -Wno-unused-parameter -Wwrite-strings -Wno-missing-field-initializers -Wno-long-long -Wno-maybe-uninitialized -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wno-comment -std=c++14 -fdeprecated-macro -fdebug-compilation-dir=/build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/build-llvm/tools/clang/stage2-bins -fdebug-prefix-map=/build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/build-llvm/tools/clang/stage2-bins=build-llvm/tools/clang/stage2-bins -fdebug-prefix-map=/build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/= -ferror-limit 19 -fvisibility-inlines-hidden -stack-protector 2 -fgnuc-version=4.2.1 -fcolor-diagnostics -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -faddrsig -D__GCC_HAVE_DWARF2_CFI_ASM=1 -o /tmp/scan-build-2022-01-25-232935-20746-1 -x c++ /build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/llvm/tools/llvm-libtool-darwin/llvm-libtool-darwin.cpp

/build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/llvm/tools/llvm-libtool-darwin/llvm-libtool-darwin.cpp

1//===-- llvm-libtool-darwin.cpp - a tool for creating libraries -----------===//
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// A utility for creating static and dynamic libraries for Darwin.
10//
11//===----------------------------------------------------------------------===//
12
13#include "llvm/BinaryFormat/Magic.h"
14#include "llvm/IR/LLVMContext.h"
15#include "llvm/Object/ArchiveWriter.h"
16#include "llvm/Object/IRObjectFile.h"
17#include "llvm/Object/MachO.h"
18#include "llvm/Object/MachOUniversal.h"
19#include "llvm/Object/MachOUniversalWriter.h"
20#include "llvm/Object/ObjectFile.h"
21#include "llvm/Support/CommandLine.h"
22#include "llvm/Support/InitLLVM.h"
23#include "llvm/Support/LineIterator.h"
24#include "llvm/Support/VirtualFileSystem.h"
25#include "llvm/Support/WithColor.h"
26#include "llvm/TextAPI/Architecture.h"
27#include <map>
28#include <type_traits>
29
30using namespace llvm;
31using namespace llvm::object;
32
33static LLVMContext LLVMCtx;
34
35typedef std::map<uint64_t, std::vector<NewArchiveMember>>
36 MembersPerArchitectureMap;
37
38cl::OptionCategory LibtoolCategory("llvm-libtool-darwin Options");
39
40static cl::opt<std::string> OutputFile("o", cl::desc("Specify output filename"),
41 cl::value_desc("filename"),
42 cl::cat(LibtoolCategory));
43
44static cl::list<std::string> InputFiles(cl::Positional,
45 cl::desc("<input files>"),
46 cl::ZeroOrMore,
47 cl::cat(LibtoolCategory));
48
49static cl::opt<std::string> ArchType(
50 "arch_only", cl::desc("Specify architecture type for output library"),
51 cl::value_desc("arch_type"), cl::ZeroOrMore, cl::cat(LibtoolCategory));
52
53enum class Operation { None, Static };
54
55static cl::opt<Operation> LibraryOperation(
56 cl::desc("Library Type: "),
57 cl::values(
58 clEnumValN(Operation::Static, "static",llvm::cl::OptionEnumValue { "static", int(Operation::Static),
"Produce a statically linked library from the input files" }
59 "Produce a statically linked library from the input files")llvm::cl::OptionEnumValue { "static", int(Operation::Static),
"Produce a statically linked library from the input files" }
),
60 cl::init(Operation::None), cl::cat(LibtoolCategory));
61
62static cl::opt<bool> DeterministicOption(
63 "D", cl::desc("Use zero for timestamps and UIDs/GIDs (Default)"),
64 cl::init(false), cl::cat(LibtoolCategory));
65
66static cl::opt<bool>
67 NonDeterministicOption("U", cl::desc("Use actual timestamps and UIDs/GIDs"),
68 cl::init(false), cl::cat(LibtoolCategory));
69
70static cl::opt<std::string>
71 FileList("filelist",
72 cl::desc("Pass in file containing a list of filenames"),
73 cl::value_desc("listfile[,dirname]"), cl::cat(LibtoolCategory));
74
75static cl::list<std::string> Libraries(
76 "l",
77 cl::desc(
78 "l<x> searches for the library libx.a in the library search path. If"
79 " the string 'x' ends with '.o', then the library 'x' is searched for"
80 " without prepending 'lib' or appending '.a'"),
81 cl::ZeroOrMore, cl::Prefix, cl::cat(LibtoolCategory));
82
83static cl::list<std::string> LibrarySearchDirs(
84 "L",
85 cl::desc(
86 "L<dir> adds <dir> to the list of directories in which to search for"
87 " libraries"),
88 cl::ZeroOrMore, cl::Prefix, cl::cat(LibtoolCategory));
89
90static cl::opt<bool>
91 VersionOption("V", cl::desc("Print the version number and exit"),
92 cl::cat(LibtoolCategory));
93
94static cl::opt<bool> NoWarningForNoSymbols(
95 "no_warning_for_no_symbols",
96 cl::desc("Do not warn about files that have no symbols"),
97 cl::cat(LibtoolCategory), cl::init(false));
98
99static const std::array<std::string, 3> StandardSearchDirs{
100 "/lib",
101 "/usr/lib",
102 "/usr/local/lib",
103};
104
105struct Config {
106 bool Deterministic = true; // Updated by 'D' and 'U' modifiers.
107 uint32_t ArchCPUType;
108 uint32_t ArchCPUSubtype;
109};
110
111static Expected<std::string> searchForFile(const Twine &FileName) {
112
113 auto FindLib =
114 [FileName](ArrayRef<std::string> SearchDirs) -> Optional<std::string> {
115 for (StringRef Dir : SearchDirs) {
116 SmallString<128> Path;
117 sys::path::append(Path, Dir, FileName);
118
119 if (sys::fs::exists(Path))
120 return std::string(Path);
121 }
122 return None;
123 };
124
125 Optional<std::string> Found = FindLib(LibrarySearchDirs);
126 if (!Found)
127 Found = FindLib(StandardSearchDirs);
128 if (Found)
129 return *Found;
130
131 return createStringError(std::errc::invalid_argument,
132 "cannot locate file '%s'", FileName.str().c_str());
133}
134
135static Error processCommandLineLibraries() {
136 for (StringRef BaseName : Libraries) {
137 Expected<std::string> FullPath = searchForFile(
138 BaseName.endswith(".o") ? BaseName.str() : "lib" + BaseName + ".a");
139 if (!FullPath)
140 return FullPath.takeError();
141 InputFiles.push_back(FullPath.get());
142 }
143
144 return Error::success();
145}
146
147static Error processFileList() {
148 StringRef FileName, DirName;
149 std::tie(FileName, DirName) = StringRef(FileList).rsplit(",");
150
151 ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
152 MemoryBuffer::getFileOrSTDIN(FileName, /*IsText=*/false,
153 /*RequiresNullTerminator=*/false);
154 if (std::error_code EC = FileOrErr.getError())
155 return createFileError(FileName, errorCodeToError(EC));
156 const MemoryBuffer &Ref = *FileOrErr.get();
157
158 line_iterator I(Ref, /*SkipBlanks=*/false);
159 if (I.is_at_eof())
160 return createStringError(std::errc::invalid_argument,
161 "file list file: '%s' is empty",
162 FileName.str().c_str());
163 for (; !I.is_at_eof(); ++I) {
164 StringRef Line = *I;
165 if (Line.empty())
166 return createStringError(std::errc::invalid_argument,
167 "file list file: '%s': filename cannot be empty",
168 FileName.str().c_str());
169
170 SmallString<128> Path;
171 if (!DirName.empty())
172 sys::path::append(Path, DirName, Line);
173 else
174 sys::path::append(Path, Line);
175 InputFiles.push_back(static_cast<std::string>(Path));
176 }
177 return Error::success();
178}
179
180static Error validateArchitectureName(StringRef ArchitectureName) {
181 if (!MachOObjectFile::isValidArch(ArchitectureName)) {
182 std::string Buf;
183 raw_string_ostream OS(Buf);
184 for (StringRef Arch : MachOObjectFile::getValidArchs())
185 OS << Arch << " ";
186
187 return createStringError(
188 std::errc::invalid_argument,
189 "invalid architecture '%s': valid architecture names are %s",
190 ArchitectureName.str().c_str(), OS.str().c_str());
191 }
192 return Error::success();
193}
194
195static uint64_t getCPUID(uint32_t CPUType, uint32_t CPUSubtype) {
196 switch (CPUType) {
197 case MachO::CPU_TYPE_ARM:
198 case MachO::CPU_TYPE_ARM64:
199 case MachO::CPU_TYPE_ARM64_32:
200 case MachO::CPU_TYPE_X86_64:
201 // We consider CPUSubtype only for the above 4 CPUTypes to match cctools'
202 // libtool behavior.
203 return static_cast<uint64_t>(CPUType) << 32 | CPUSubtype;
204 default:
205 return CPUType;
206 }
207}
208
209// MembersData is an organized collection of members.
210struct MembersData {
211 // MembersPerArchitectureMap is a mapping from CPU architecture to a list of
212 // members.
213 MembersPerArchitectureMap MembersPerArchitecture;
214 std::vector<std::unique_ptr<MemoryBuffer>> FileBuffers;
215
216 static_assert(!std::is_copy_constructible<NewArchiveMember>::value,
217 "MembersPerArchitecture has a dependency on FileBuffers so it "
218 "should not be able to be copied on its own without "
219 "FileBuffers.");
220 static_assert(!std::is_copy_assignable<NewArchiveMember>::value,
221 "MembersPerArchitecture has a dependency on FileBuffers so it "
222 "should not be able to be copied on its own without "
223 "FileBuffers.");
224};
225
226// MembersBuilder collects and organizes all members from the files provided by
227// the user.
228class MembersBuilder {
229public:
230 MembersBuilder(const Config &C) : C(C) {}
231
232 Expected<MembersData> build() {
233 for (StringRef FileName : InputFiles)
234 if (Error E = addMember(FileName))
7
Calling 'MembersBuilder::addMember'
235 return std::move(E);
236
237 if (!ArchType.empty()) {
238 uint64_t ArchCPUID = getCPUID(C.ArchCPUType, C.ArchCPUSubtype);
239 if (Data.MembersPerArchitecture.find(ArchCPUID) ==
240 Data.MembersPerArchitecture.end())
241 return createStringError(std::errc::invalid_argument,
242 "no library created (no object files in input "
243 "files matching -arch_only %s)",
244 ArchType.c_str());
245 }
246 return std::move(Data);
247 }
248
249private:
250 // Check that a file's architecture [FileCPUType, FileCPUSubtype]
251 // matches the architecture specified under -arch_only flag.
252 bool acceptFileArch(uint32_t FileCPUType, uint32_t FileCPUSubtype) {
253 if (C.ArchCPUType != FileCPUType)
254 return false;
255
256 switch (C.ArchCPUType) {
257 case MachO::CPU_TYPE_ARM:
258 case MachO::CPU_TYPE_ARM64_32:
259 case MachO::CPU_TYPE_X86_64:
260 return C.ArchCPUSubtype == FileCPUSubtype;
261
262 case MachO::CPU_TYPE_ARM64:
263 if (C.ArchCPUSubtype == MachO::CPU_SUBTYPE_ARM64_ALL)
264 return FileCPUSubtype == MachO::CPU_SUBTYPE_ARM64_ALL ||
265 FileCPUSubtype == MachO::CPU_SUBTYPE_ARM64_V8;
266 else
267 return C.ArchCPUSubtype == FileCPUSubtype;
268
269 default:
270 return true;
271 }
272 }
273
274 Error verifyAndAddMachOObject(NewArchiveMember Member) {
275 auto MBRef = Member.Buf->getMemBufferRef();
276 Expected<std::unique_ptr<object::ObjectFile>> ObjOrErr =
277 object::ObjectFile::createObjectFile(MBRef);
278
279 // Throw error if not a valid object file.
280 if (!ObjOrErr)
16
Calling 'Expected::operator bool'
19
Returning from 'Expected::operator bool'
20
Taking false branch
281 return createFileError(Member.MemberName, ObjOrErr.takeError());
282
283 // Throw error if not in Mach-O format.
284 if (!isa<object::MachOObjectFile>(**ObjOrErr))
21
Assuming the object is a 'MachOObjectFile'
22
Taking false branch
285 return createStringError(std::errc::invalid_argument,
286 "'%s': format not supported",
287 Member.MemberName.data());
288
289 auto *O = dyn_cast<MachOObjectFile>(ObjOrErr->get());
23
Assuming the object is not a 'MachOObjectFile'
24
'O' initialized to a null pointer value
290 uint32_t FileCPUType, FileCPUSubtype;
291 std::tie(FileCPUType, FileCPUSubtype) = MachO::getCPUTypeFromArchitecture(
292 MachO::getArchitectureFromName(O->getArchTriple().getArchName()));
25
Called C++ object pointer is null
293
294 // If -arch_only is specified then skip this file if it doesn't match
295 // the architecture specified.
296 if (!ArchType.empty() && !acceptFileArch(FileCPUType, FileCPUSubtype)) {
297 return Error::success();
298 }
299
300 if (!NoWarningForNoSymbols && O->symbols().empty())
301 WithColor::warning() << Member.MemberName + " has no symbols\n";
302
303 uint64_t FileCPUID = getCPUID(FileCPUType, FileCPUSubtype);
304 Data.MembersPerArchitecture[FileCPUID].push_back(std::move(Member));
305 return Error::success();
306 }
307
308 Error verifyAndAddIRObject(NewArchiveMember Member) {
309 auto MBRef = Member.Buf->getMemBufferRef();
310 Expected<std::unique_ptr<object::IRObjectFile>> IROrErr =
311 object::IRObjectFile::create(MBRef, LLVMCtx);
312
313 // Throw error if not a valid IR object file.
314 if (!IROrErr)
315 return createFileError(Member.MemberName, IROrErr.takeError());
316
317 Triple TT = Triple(IROrErr->get()->getTargetTriple());
318
319 Expected<uint32_t> FileCPUTypeOrErr = MachO::getCPUType(TT);
320 if (!FileCPUTypeOrErr)
321 return FileCPUTypeOrErr.takeError();
322
323 Expected<uint32_t> FileCPUSubTypeOrErr = MachO::getCPUSubType(TT);
324 if (!FileCPUSubTypeOrErr)
325 return FileCPUSubTypeOrErr.takeError();
326
327 // If -arch_only is specified then skip this file if it doesn't match
328 // the architecture specified.
329 if (!ArchType.empty() &&
330 !acceptFileArch(*FileCPUTypeOrErr, *FileCPUSubTypeOrErr)) {
331 return Error::success();
332 }
333
334 uint64_t FileCPUID = getCPUID(*FileCPUTypeOrErr, *FileCPUSubTypeOrErr);
335 Data.MembersPerArchitecture[FileCPUID].push_back(std::move(Member));
336 return Error::success();
337 }
338
339 Error addChildMember(const object::Archive::Child &M) {
340 Expected<NewArchiveMember> NewMemberOrErr =
341 NewArchiveMember::getOldMember(M, C.Deterministic);
342 if (!NewMemberOrErr)
343 return NewMemberOrErr.takeError();
344 auto &NewMember = *NewMemberOrErr;
345
346 file_magic Magic = identify_magic(NewMember.Buf->getBuffer());
347
348 if (Magic == file_magic::bitcode)
349 return verifyAndAddIRObject(std::move(NewMember));
350
351 return verifyAndAddMachOObject(std::move(NewMember));
352 }
353
354 Error processArchive(object::Archive &Lib, StringRef FileName) {
355 Error Err = Error::success();
356 for (const object::Archive::Child &Child : Lib.children(Err))
357 if (Error E = addChildMember(Child))
358 return createFileError(FileName, std::move(E));
359 if (Err)
360 return createFileError(FileName, std::move(Err));
361
362 return Error::success();
363 }
364
365 Error addArchiveMembers(NewArchiveMember NewMember, StringRef FileName) {
366 Expected<std::unique_ptr<Archive>> LibOrErr =
367 object::Archive::create(NewMember.Buf->getMemBufferRef());
368 if (!LibOrErr)
369 return createFileError(FileName, LibOrErr.takeError());
370
371 if (Error E = processArchive(**LibOrErr, FileName))
372 return E;
373
374 // Update vector FileBuffers with the MemoryBuffers to transfer
375 // ownership.
376 Data.FileBuffers.push_back(std::move(NewMember.Buf));
377 return Error::success();
378 }
379
380 Error addUniversalMembers(NewArchiveMember NewMember, StringRef FileName) {
381 Expected<std::unique_ptr<MachOUniversalBinary>> BinaryOrErr =
382 MachOUniversalBinary::create(NewMember.Buf->getMemBufferRef());
383 if (!BinaryOrErr)
384 return createFileError(FileName, BinaryOrErr.takeError());
385
386 auto *UO = BinaryOrErr->get();
387 for (const MachOUniversalBinary::ObjectForArch &O : UO->objects()) {
388
389 Expected<std::unique_ptr<MachOObjectFile>> MachOObjOrErr =
390 O.getAsObjectFile();
391 if (MachOObjOrErr) {
392 NewArchiveMember NewMember =
393 NewArchiveMember(MachOObjOrErr->get()->getMemoryBufferRef());
394 NewMember.MemberName = sys::path::filename(NewMember.MemberName);
395
396 if (Error E = verifyAndAddMachOObject(std::move(NewMember)))
397 return E;
398 continue;
399 }
400
401 Expected<std::unique_ptr<IRObjectFile>> IRObjectOrError =
402 O.getAsIRObject(LLVMCtx);
403 if (IRObjectOrError) {
404 // A universal file member can be a MachOObjectFile, an IRObject or an
405 // Archive. In case we can successfully cast the member as an IRObject,
406 // it is safe to throw away the error generated due to casting the
407 // object as a MachOObjectFile.
408 consumeError(MachOObjOrErr.takeError());
409
410 NewArchiveMember NewMember =
411 NewArchiveMember(IRObjectOrError->get()->getMemoryBufferRef());
412 NewMember.MemberName = sys::path::filename(NewMember.MemberName);
413
414 if (Error E = verifyAndAddIRObject(std::move(NewMember)))
415 return E;
416 continue;
417 }
418
419 Expected<std::unique_ptr<Archive>> ArchiveOrError = O.getAsArchive();
420 if (ArchiveOrError) {
421 // A universal file member can be a MachOObjectFile, an IRObject or an
422 // Archive. In case we can successfully cast the member as an Archive,
423 // it is safe to throw away the error generated due to casting the
424 // object as a MachOObjectFile.
425 consumeError(MachOObjOrErr.takeError());
426 consumeError(IRObjectOrError.takeError());
427
428 if (Error E = processArchive(**ArchiveOrError, FileName))
429 return E;
430 continue;
431 }
432
433 Error CombinedError = joinErrors(
434 ArchiveOrError.takeError(),
435 joinErrors(IRObjectOrError.takeError(), MachOObjOrErr.takeError()));
436 return createFileError(FileName, std::move(CombinedError));
437 }
438
439 // Update vector FileBuffers with the MemoryBuffers to transfer
440 // ownership.
441 Data.FileBuffers.push_back(std::move(NewMember.Buf));
442 return Error::success();
443 }
444
445 Error addMember(StringRef FileName) {
446 Expected<NewArchiveMember> NewMemberOrErr =
447 NewArchiveMember::getFile(FileName, C.Deterministic);
448 if (!NewMemberOrErr)
8
Taking false branch
449 return createFileError(FileName, NewMemberOrErr.takeError());
450 auto &NewMember = *NewMemberOrErr;
451
452 // For regular archives, use the basename of the object path for the member
453 // name.
454 NewMember.MemberName = sys::path::filename(NewMember.MemberName);
455 file_magic Magic = identify_magic(NewMember.Buf->getBuffer());
456
457 // Flatten archives.
458 if (Magic == file_magic::archive)
9
Assuming the condition is false
10
Taking false branch
459 return addArchiveMembers(std::move(NewMember), FileName);
460
461 // Flatten universal files.
462 if (Magic == file_magic::macho_universal_binary)
11
Assuming the condition is false
12
Taking false branch
463 return addUniversalMembers(std::move(NewMember), FileName);
464
465 // Bitcode files.
466 if (Magic == file_magic::bitcode)
13
Assuming the condition is false
14
Taking false branch
467 return verifyAndAddIRObject(std::move(NewMember));
468
469 return verifyAndAddMachOObject(std::move(NewMember));
15
Calling 'MembersBuilder::verifyAndAddMachOObject'
470 }
471
472 MembersData Data;
473 const Config &C;
474};
475
476static Expected<SmallVector<Slice, 2>>
477buildSlices(ArrayRef<OwningBinary<Archive>> OutputBinaries) {
478 SmallVector<Slice, 2> Slices;
479
480 for (const auto &OB : OutputBinaries) {
481 const Archive &A = *OB.getBinary();
482 Expected<Slice> ArchiveSlice = Slice::create(A, &LLVMCtx);
483 if (!ArchiveSlice)
484 return ArchiveSlice.takeError();
485 Slices.push_back(*ArchiveSlice);
486 }
487 return Slices;
488}
489
490static Error createStaticLibrary(const Config &C) {
491 MembersBuilder Builder(C);
492 auto DataOrError = Builder.build();
6
Calling 'MembersBuilder::build'
493 if (auto Error = DataOrError.takeError())
494 return Error;
495
496 const auto &NewMembers = DataOrError->MembersPerArchitecture;
497
498 if (NewMembers.size() == 1) {
499 return writeArchive(OutputFile, NewMembers.begin()->second,
500 /*WriteSymtab=*/true,
501 /*Kind=*/object::Archive::K_DARWIN, C.Deterministic,
502 /*Thin=*/false);
503 }
504
505 SmallVector<OwningBinary<Archive>, 2> OutputBinaries;
506 for (const std::pair<const uint64_t, std::vector<NewArchiveMember>> &M :
507 NewMembers) {
508 Expected<std::unique_ptr<MemoryBuffer>> OutputBufferOrErr =
509 writeArchiveToBuffer(M.second,
510 /*WriteSymtab=*/true,
511 /*Kind=*/object::Archive::K_DARWIN,
512 C.Deterministic,
513 /*Thin=*/false);
514 if (!OutputBufferOrErr)
515 return OutputBufferOrErr.takeError();
516 std::unique_ptr<MemoryBuffer> &OutputBuffer = OutputBufferOrErr.get();
517
518 Expected<std::unique_ptr<Archive>> ArchiveOrError =
519 Archive::create(OutputBuffer->getMemBufferRef());
520 if (!ArchiveOrError)
521 return ArchiveOrError.takeError();
522 std::unique_ptr<Archive> &A = ArchiveOrError.get();
523
524 OutputBinaries.push_back(
525 OwningBinary<Archive>(std::move(A), std::move(OutputBuffer)));
526 }
527
528 Expected<SmallVector<Slice, 2>> Slices = buildSlices(OutputBinaries);
529 if (!Slices)
530 return Slices.takeError();
531
532 llvm::stable_sort(*Slices);
533 return writeUniversalBinary(*Slices, OutputFile);
534}
535
536static Expected<Config> parseCommandLine(int Argc, char **Argv) {
537 Config C;
538 cl::ParseCommandLineOptions(Argc, Argv, "llvm-libtool-darwin\n");
539
540 if (LibraryOperation == Operation::None) {
541 if (!VersionOption) {
542 std::string Error;
543 raw_string_ostream Stream(Error);
544 LibraryOperation.error("must be specified", "", Stream);
545 return createStringError(std::errc::invalid_argument, Error.c_str());
546 }
547 return C;
548 }
549
550 if (OutputFile.empty()) {
551 std::string Error;
552 raw_string_ostream Stream(Error);
553 OutputFile.error("must be specified", "o", Stream);
554 return createStringError(std::errc::invalid_argument, Error.c_str());
555 }
556
557 if (DeterministicOption && NonDeterministicOption)
558 return createStringError(std::errc::invalid_argument,
559 "cannot specify both -D and -U flags");
560 else if (NonDeterministicOption)
561 C.Deterministic = false;
562
563 if (!Libraries.empty())
564 if (Error E = processCommandLineLibraries())
565 return std::move(E);
566
567 if (!FileList.empty())
568 if (Error E = processFileList())
569 return std::move(E);
570
571 if (InputFiles.empty())
572 return createStringError(std::errc::invalid_argument,
573 "no input files specified");
574
575 if (ArchType.getNumOccurrences()) {
576 if (Error E = validateArchitectureName(ArchType))
577 return std::move(E);
578
579 std::tie(C.ArchCPUType, C.ArchCPUSubtype) =
580 MachO::getCPUTypeFromArchitecture(
581 MachO::getArchitectureFromName(ArchType));
582 }
583
584 return C;
585}
586
587int main(int Argc, char **Argv) {
588 InitLLVM X(Argc, Argv);
589 cl::HideUnrelatedOptions({&LibtoolCategory, &getColorCategory()});
590 Expected<Config> ConfigOrErr = parseCommandLine(Argc, Argv);
591 if (!ConfigOrErr) {
1
Taking false branch
592 WithColor::defaultErrorHandler(ConfigOrErr.takeError());
593 return EXIT_FAILURE1;
594 }
595
596 if (VersionOption)
2
Assuming the condition is false
3
Taking false branch
597 cl::PrintVersionMessage();
598
599 Config C = *ConfigOrErr;
600 switch (LibraryOperation) {
4
Control jumps to 'case Static:' at line 603
601 case Operation::None:
602 break;
603 case Operation::Static:
604 if (Error E = createStaticLibrary(C)) {
5
Calling 'createStaticLibrary'
605 WithColor::defaultErrorHandler(std::move(E));
606 return EXIT_FAILURE1;
607 }
608 break;
609 }
610}

/build/llvm-toolchain-snapshot-14~++20220125101009+ceec4383681c/llvm/include/llvm/Support/Error.h

1//===- llvm/Support/Error.h - Recoverable error handling --------*- 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// This file defines an API used to report recoverable errors.
10//
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_SUPPORT_ERROR_H
14#define LLVM_SUPPORT_ERROR_H
15
16#include "llvm-c/Error.h"
17#include "llvm/ADT/SmallVector.h"
18#include "llvm/ADT/StringExtras.h"
19#include "llvm/ADT/Twine.h"
20#include "llvm/Config/abi-breaking.h"
21#include "llvm/Support/AlignOf.h"
22#include "llvm/Support/Compiler.h"
23#include "llvm/Support/Debug.h"
24#include "llvm/Support/ErrorHandling.h"
25#include "llvm/Support/ErrorOr.h"
26#include "llvm/Support/Format.h"
27#include "llvm/Support/raw_ostream.h"
28#include <cassert>
29#include <cstdint>
30#include <cstdlib>
31#include <functional>
32#include <memory>
33#include <new>
34#include <string>
35#include <system_error>
36#include <type_traits>
37#include <utility>
38#include <vector>
39
40namespace llvm {
41
42class ErrorSuccess;
43
44/// Base class for error info classes. Do not extend this directly: Extend
45/// the ErrorInfo template subclass instead.
46class ErrorInfoBase {
47public:
48 virtual ~ErrorInfoBase() = default;
49
50 /// Print an error message to an output stream.
51 virtual void log(raw_ostream &OS) const = 0;
52
53 /// Return the error message as a string.
54 virtual std::string message() const {
55 std::string Msg;
56 raw_string_ostream OS(Msg);
57 log(OS);
58 return OS.str();
59 }
60
61 /// Convert this error to a std::error_code.
62 ///
63 /// This is a temporary crutch to enable interaction with code still
64 /// using std::error_code. It will be removed in the future.
65 virtual std::error_code convertToErrorCode() const = 0;
66
67 // Returns the class ID for this type.
68 static const void *classID() { return &ID; }
69
70 // Returns the class ID for the dynamic type of this ErrorInfoBase instance.
71 virtual const void *dynamicClassID() const = 0;
72
73 // Check whether this instance is a subclass of the class identified by
74 // ClassID.
75 virtual bool isA(const void *const ClassID) const {
76 return ClassID == classID();
77 }
78
79 // Check whether this instance is a subclass of ErrorInfoT.
80 template <typename ErrorInfoT> bool isA() const {
81 return isA(ErrorInfoT::classID());
82 }
83
84private:
85 virtual void anchor();
86
87 static char ID;
88};
89
90/// Lightweight error class with error context and mandatory checking.
91///
92/// Instances of this class wrap a ErrorInfoBase pointer. Failure states
93/// are represented by setting the pointer to a ErrorInfoBase subclass
94/// instance containing information describing the failure. Success is
95/// represented by a null pointer value.
96///
97/// Instances of Error also contains a 'Checked' flag, which must be set
98/// before the destructor is called, otherwise the destructor will trigger a
99/// runtime error. This enforces at runtime the requirement that all Error
100/// instances be checked or returned to the caller.
101///
102/// There are two ways to set the checked flag, depending on what state the
103/// Error instance is in. For Error instances indicating success, it
104/// is sufficient to invoke the boolean conversion operator. E.g.:
105///
106/// @code{.cpp}
107/// Error foo(<...>);
108///
109/// if (auto E = foo(<...>))
110/// return E; // <- Return E if it is in the error state.
111/// // We have verified that E was in the success state. It can now be safely
112/// // destroyed.
113/// @endcode
114///
115/// A success value *can not* be dropped. For example, just calling 'foo(<...>)'
116/// without testing the return value will raise a runtime error, even if foo
117/// returns success.
118///
119/// For Error instances representing failure, you must use either the
120/// handleErrors or handleAllErrors function with a typed handler. E.g.:
121///
122/// @code{.cpp}
123/// class MyErrorInfo : public ErrorInfo<MyErrorInfo> {
124/// // Custom error info.
125/// };
126///
127/// Error foo(<...>) { return make_error<MyErrorInfo>(...); }
128///
129/// auto E = foo(<...>); // <- foo returns failure with MyErrorInfo.
130/// auto NewE =
131/// handleErrors(E,
132/// [](const MyErrorInfo &M) {
133/// // Deal with the error.
134/// },
135/// [](std::unique_ptr<OtherError> M) -> Error {
136/// if (canHandle(*M)) {
137/// // handle error.
138/// return Error::success();
139/// }
140/// // Couldn't handle this error instance. Pass it up the stack.
141/// return Error(std::move(M));
142/// );
143/// // Note - we must check or return NewE in case any of the handlers
144/// // returned a new error.
145/// @endcode
146///
147/// The handleAllErrors function is identical to handleErrors, except
148/// that it has a void return type, and requires all errors to be handled and
149/// no new errors be returned. It prevents errors (assuming they can all be
150/// handled) from having to be bubbled all the way to the top-level.
151///
152/// *All* Error instances must be checked before destruction, even if
153/// they're moved-assigned or constructed from Success values that have already
154/// been checked. This enforces checking through all levels of the call stack.
155class LLVM_NODISCARD[[clang::warn_unused_result]] Error {
156 // ErrorList needs to be able to yank ErrorInfoBase pointers out of Errors
157 // to add to the error list. It can't rely on handleErrors for this, since
158 // handleErrors does not support ErrorList handlers.
159 friend class ErrorList;
160
161 // handleErrors needs to be able to set the Checked flag.
162 template <typename... HandlerTs>
163 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
164
165 // Expected<T> needs to be able to steal the payload when constructed from an
166 // error.
167 template <typename T> friend class Expected;
168
169 // wrap needs to be able to steal the payload.
170 friend LLVMErrorRef wrap(Error);
171
172protected:
173 /// Create a success value. Prefer using 'Error::success()' for readability
174 Error() {
175 setPtr(nullptr);
176 setChecked(false);
177 }
178
179public:
180 /// Create a success value.
181 static ErrorSuccess success();
182
183 // Errors are not copy-constructable.
184 Error(const Error &Other) = delete;
185
186 /// Move-construct an error value. The newly constructed error is considered
187 /// unchecked, even if the source error had been checked. The original error
188 /// becomes a checked Success value, regardless of its original state.
189 Error(Error &&Other) {
190 setChecked(true);
191 *this = std::move(Other);
192 }
193
194 /// Create an error value. Prefer using the 'make_error' function, but
195 /// this constructor can be useful when "re-throwing" errors from handlers.
196 Error(std::unique_ptr<ErrorInfoBase> Payload) {
197 setPtr(Payload.release());
198 setChecked(false);
199 }
200
201 // Errors are not copy-assignable.
202 Error &operator=(const Error &Other) = delete;
203
204 /// Move-assign an error value. The current error must represent success, you
205 /// you cannot overwrite an unhandled error. The current error is then
206 /// considered unchecked. The source error becomes a checked success value,
207 /// regardless of its original state.
208 Error &operator=(Error &&Other) {
209 // Don't allow overwriting of unchecked values.
210 assertIsChecked();
211 setPtr(Other.getPtr());
212
213 // This Error is unchecked, even if the source error was checked.
214 setChecked(false);
215
216 // Null out Other's payload and set its checked bit.
217 Other.setPtr(nullptr);
218 Other.setChecked(true);
219
220 return *this;
221 }
222
223 /// Destroy a Error. Fails with a call to abort() if the error is
224 /// unchecked.
225 ~Error() {
226 assertIsChecked();
227 delete getPtr();
228 }
229
230 /// Bool conversion. Returns true if this Error is in a failure state,
231 /// and false if it is in an accept state. If the error is in a Success state
232 /// it will be considered checked.
233 explicit operator bool() {
234 setChecked(getPtr() == nullptr);
235 return getPtr() != nullptr;
236 }
237
238 /// Check whether one error is a subclass of another.
239 template <typename ErrT> bool isA() const {
240 return getPtr() && getPtr()->isA(ErrT::classID());
241 }
242
243 /// Returns the dynamic class id of this error, or null if this is a success
244 /// value.
245 const void* dynamicClassID() const {
246 if (!getPtr())
247 return nullptr;
248 return getPtr()->dynamicClassID();
249 }
250
251private:
252#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
253 // assertIsChecked() happens very frequently, but under normal circumstances
254 // is supposed to be a no-op. So we want it to be inlined, but having a bunch
255 // of debug prints can cause the function to be too large for inlining. So
256 // it's important that we define this function out of line so that it can't be
257 // inlined.
258 [[noreturn]] void fatalUncheckedError() const;
259#endif
260
261 void assertIsChecked() {
262#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
263 if (LLVM_UNLIKELY(!getChecked() || getPtr())__builtin_expect((bool)(!getChecked() || getPtr()), false))
264 fatalUncheckedError();
265#endif
266 }
267
268 ErrorInfoBase *getPtr() const {
269#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
270 return reinterpret_cast<ErrorInfoBase*>(
271 reinterpret_cast<uintptr_t>(Payload) &
272 ~static_cast<uintptr_t>(0x1));
273#else
274 return Payload;
275#endif
276 }
277
278 void setPtr(ErrorInfoBase *EI) {
279#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
280 Payload = reinterpret_cast<ErrorInfoBase*>(
281 (reinterpret_cast<uintptr_t>(EI) &
282 ~static_cast<uintptr_t>(0x1)) |
283 (reinterpret_cast<uintptr_t>(Payload) & 0x1));
284#else
285 Payload = EI;
286#endif
287 }
288
289 bool getChecked() const {
290#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
291 return (reinterpret_cast<uintptr_t>(Payload) & 0x1) == 0;
292#else
293 return true;
294#endif
295 }
296
297 void setChecked(bool V) {
298#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
299 Payload = reinterpret_cast<ErrorInfoBase*>(
300 (reinterpret_cast<uintptr_t>(Payload) &
301 ~static_cast<uintptr_t>(0x1)) |
302 (V ? 0 : 1));
303#endif
304 }
305
306 std::unique_ptr<ErrorInfoBase> takePayload() {
307 std::unique_ptr<ErrorInfoBase> Tmp(getPtr());
308 setPtr(nullptr);
309 setChecked(true);
310 return Tmp;
311 }
312
313 friend raw_ostream &operator<<(raw_ostream &OS, const Error &E) {
314 if (auto *P = E.getPtr())
315 P->log(OS);
316 else
317 OS << "success";
318 return OS;
319 }
320
321 ErrorInfoBase *Payload = nullptr;
322};
323
324/// Subclass of Error for the sole purpose of identifying the success path in
325/// the type system. This allows to catch invalid conversion to Expected<T> at
326/// compile time.
327class ErrorSuccess final : public Error {};
328
329inline ErrorSuccess Error::success() { return ErrorSuccess(); }
330
331/// Make a Error instance representing failure using the given error info
332/// type.
333template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&... Args) {
334 return Error(std::make_unique<ErrT>(std::forward<ArgTs>(Args)...));
335}
336
337/// Base class for user error types. Users should declare their error types
338/// like:
339///
340/// class MyError : public ErrorInfo<MyError> {
341/// ....
342/// };
343///
344/// This class provides an implementation of the ErrorInfoBase::kind
345/// method, which is used by the Error RTTI system.
346template <typename ThisErrT, typename ParentErrT = ErrorInfoBase>
347class ErrorInfo : public ParentErrT {
348public:
349 using ParentErrT::ParentErrT; // inherit constructors
350
351 static const void *classID() { return &ThisErrT::ID; }
352
353 const void *dynamicClassID() const override { return &ThisErrT::ID; }
354
355 bool isA(const void *const ClassID) const override {
356 return ClassID == classID() || ParentErrT::isA(ClassID);
357 }
358};
359
360/// Special ErrorInfo subclass representing a list of ErrorInfos.
361/// Instances of this class are constructed by joinError.
362class ErrorList final : public ErrorInfo<ErrorList> {
363 // handleErrors needs to be able to iterate the payload list of an
364 // ErrorList.
365 template <typename... HandlerTs>
366 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
367
368 // joinErrors is implemented in terms of join.
369 friend Error joinErrors(Error, Error);
370
371public:
372 void log(raw_ostream &OS) const override {
373 OS << "Multiple errors:\n";
374 for (const auto &ErrPayload : Payloads) {
375 ErrPayload->log(OS);
376 OS << "\n";
377 }
378 }
379
380 std::error_code convertToErrorCode() const override;
381
382 // Used by ErrorInfo::classID.
383 static char ID;
384
385private:
386 ErrorList(std::unique_ptr<ErrorInfoBase> Payload1,
387 std::unique_ptr<ErrorInfoBase> Payload2) {
388 assert(!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() &&(static_cast <bool> (!Payload1->isA<ErrorList>
() && !Payload2->isA<ErrorList>() &&
"ErrorList constructor payloads should be singleton errors")
? void (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "llvm/include/llvm/Support/Error.h", 389, __extension__ __PRETTY_FUNCTION__
))
389 "ErrorList constructor payloads should be singleton errors")(static_cast <bool> (!Payload1->isA<ErrorList>
() && !Payload2->isA<ErrorList>() &&
"ErrorList constructor payloads should be singleton errors")
? void (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "llvm/include/llvm/Support/Error.h", 389, __extension__ __PRETTY_FUNCTION__
))
;
390 Payloads.push_back(std::move(Payload1));
391 Payloads.push_back(std::move(Payload2));
392 }
393
394 static Error join(Error E1, Error E2) {
395 if (!E1)
396 return E2;
397 if (!E2)
398 return E1;
399 if (E1.isA<ErrorList>()) {
400 auto &E1List = static_cast<ErrorList &>(*E1.getPtr());
401 if (E2.isA<ErrorList>()) {
402 auto E2Payload = E2.takePayload();
403 auto &E2List = static_cast<ErrorList &>(*E2Payload);
404 for (auto &Payload : E2List.Payloads)
405 E1List.Payloads.push_back(std::move(Payload));
406 } else
407 E1List.Payloads.push_back(E2.takePayload());
408
409 return E1;
410 }
411 if (E2.isA<ErrorList>()) {
412 auto &E2List = static_cast<ErrorList &>(*E2.getPtr());
413 E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload());
414 return E2;
415 }
416 return Error(std::unique_ptr<ErrorList>(
417 new ErrorList(E1.takePayload(), E2.takePayload())));
418 }
419
420 std::vector<std::unique_ptr<ErrorInfoBase>> Payloads;
421};
422
423/// Concatenate errors. The resulting Error is unchecked, and contains the
424/// ErrorInfo(s), if any, contained in E1, followed by the
425/// ErrorInfo(s), if any, contained in E2.
426inline Error joinErrors(Error E1, Error E2) {
427 return ErrorList::join(std::move(E1), std::move(E2));
428}
429
430/// Tagged union holding either a T or a Error.
431///
432/// This class parallels ErrorOr, but replaces error_code with Error. Since
433/// Error cannot be copied, this class replaces getError() with
434/// takeError(). It also adds an bool errorIsA<ErrT>() method for testing the
435/// error class type.
436///
437/// Example usage of 'Expected<T>' as a function return type:
438///
439/// @code{.cpp}
440/// Expected<int> myDivide(int A, int B) {
441/// if (B == 0) {
442/// // return an Error
443/// return createStringError(inconvertibleErrorCode(),
444/// "B must not be zero!");
445/// }
446/// // return an integer
447/// return A / B;
448/// }
449/// @endcode
450///
451/// Checking the results of to a function returning 'Expected<T>':
452/// @code{.cpp}
453/// if (auto E = Result.takeError()) {
454/// // We must consume the error. Typically one of:
455/// // - return the error to our caller
456/// // - toString(), when logging
457/// // - consumeError(), to silently swallow the error
458/// // - handleErrors(), to distinguish error types
459/// errs() << "Problem with division " << toString(std::move(E)) << "\n";
460/// return;
461/// }
462/// // use the result
463/// outs() << "The answer is " << *Result << "\n";
464/// @endcode
465///
466/// For unit-testing a function returning an 'Expceted<T>', see the
467/// 'EXPECT_THAT_EXPECTED' macros in llvm/Testing/Support/Error.h
468
469template <class T> class LLVM_NODISCARD[[clang::warn_unused_result]] Expected {
470 template <class T1> friend class ExpectedAsOutParameter;
471 template <class OtherT> friend class Expected;
472
473 static constexpr bool isRef = std::is_reference<T>::value;
474
475 using wrap = std::reference_wrapper<std::remove_reference_t<T>>;
476
477 using error_type = std::unique_ptr<ErrorInfoBase>;
478
479public:
480 using storage_type = std::conditional_t<isRef, wrap, T>;
481 using value_type = T;
482
483private:
484 using reference = std::remove_reference_t<T> &;
485 using const_reference = const std::remove_reference_t<T> &;
486 using pointer = std::remove_reference_t<T> *;
487 using const_pointer = const std::remove_reference_t<T> *;
488
489public:
490 /// Create an Expected<T> error value from the given Error.
491 Expected(Error Err)
492 : HasError(true)
493#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
494 // Expected is unchecked upon construction in Debug builds.
495 , Unchecked(true)
496#endif
497 {
498 assert(Err && "Cannot create Expected<T> from Error success value.")(static_cast <bool> (Err && "Cannot create Expected<T> from Error success value."
) ? void (0) : __assert_fail ("Err && \"Cannot create Expected<T> from Error success value.\""
, "llvm/include/llvm/Support/Error.h", 498, __extension__ __PRETTY_FUNCTION__
))
;
499 new (getErrorStorage()) error_type(Err.takePayload());
500 }
501
502 /// Forbid to convert from Error::success() implicitly, this avoids having
503 /// Expected<T> foo() { return Error::success(); } which compiles otherwise
504 /// but triggers the assertion above.
505 Expected(ErrorSuccess) = delete;
506
507 /// Create an Expected<T> success value from the given OtherT value, which
508 /// must be convertible to T.
509 template <typename OtherT>
510 Expected(OtherT &&Val,
511 std::enable_if_t<std::is_convertible<OtherT, T>::value> * = nullptr)
512 : HasError(false)
513#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
514 // Expected is unchecked upon construction in Debug builds.
515 ,
516 Unchecked(true)
517#endif
518 {
519 new (getStorage()) storage_type(std::forward<OtherT>(Val));
520 }
521
522 /// Move construct an Expected<T> value.
523 Expected(Expected &&Other) { moveConstruct(std::move(Other)); }
524
525 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
526 /// must be convertible to T.
527 template <class OtherT>
528 Expected(
529 Expected<OtherT> &&Other,
530 std::enable_if_t<std::is_convertible<OtherT, T>::value> * = nullptr) {
531 moveConstruct(std::move(Other));
532 }
533
534 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
535 /// isn't convertible to T.
536 template <class OtherT>
537 explicit Expected(
538 Expected<OtherT> &&Other,
539 std::enable_if_t<!std::is_convertible<OtherT, T>::value> * = nullptr) {
540 moveConstruct(std::move(Other));
541 }
542
543 /// Move-assign from another Expected<T>.
544 Expected &operator=(Expected &&Other) {
545 moveAssign(std::move(Other));
546 return *this;
547 }
548
549 /// Destroy an Expected<T>.
550 ~Expected() {
551 assertIsChecked();
552 if (!HasError)
553 getStorage()->~storage_type();
554 else
555 getErrorStorage()->~error_type();
556 }
557
558 /// Return false if there is an error.
559 explicit operator bool() {
560#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
561 Unchecked = HasError;
562#endif
563 return !HasError;
17
Assuming field 'HasError' is false, which participates in a condition later
18
Returning the value 1, which participates in a condition later
564 }
565
566 /// Returns a reference to the stored T value.
567 reference get() {
568 assertIsChecked();
569 return *getStorage();
570 }
571
572 /// Returns a const reference to the stored T value.
573 const_reference get() const {
574 assertIsChecked();
575 return const_cast<Expected<T> *>(this)->get();
576 }
577
578 /// Returns \a takeError() after moving the held T (if any) into \p V.
579 template <class OtherT>
580 Error moveInto(OtherT &Value,
581 std::enable_if_t<std::is_assignable<OtherT &, T &&>::value> * =
582 nullptr) && {
583 if (*this)
584 Value = std::move(get());
585 return takeError();
586 }
587
588 /// Check that this Expected<T> is an error of type ErrT.
589 template <typename ErrT> bool errorIsA() const {
590 return HasError && (*getErrorStorage())->template isA<ErrT>();
591 }
592
593 /// Take ownership of the stored error.
594 /// After calling this the Expected<T> is in an indeterminate state that can
595 /// only be safely destructed. No further calls (beside the destructor) should
596 /// be made on the Expected<T> value.
597 Error takeError() {
598#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
599 Unchecked = false;
600#endif
601 return HasError ? Error(std::move(*getErrorStorage())) : Error::success();
602 }
603
604 /// Returns a pointer to the stored T value.
605 pointer operator->() {
606 assertIsChecked();
607 return toPointer(getStorage());
608 }
609
610 /// Returns a const pointer to the stored T value.
611 const_pointer operator->() const {
612 assertIsChecked();
613 return toPointer(getStorage());
614 }
615
616 /// Returns a reference to the stored T value.
617 reference operator*() {
618 assertIsChecked();
619 return *getStorage();
620 }
621
622 /// Returns a const reference to the stored T value.
623 const_reference operator*() const {
624 assertIsChecked();
625 return *getStorage();
626 }
627
628private:
629 template <class T1>
630 static bool compareThisIfSameType(const T1 &a, const T1 &b) {
631 return &a == &b;
632 }
633
634 template <class T1, class T2>
635 static bool compareThisIfSameType(const T1 &, const T2 &) {
636 return false;
637 }
638
639 template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) {
640 HasError = Other.HasError;
641#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
642 Unchecked = true;
643 Other.Unchecked = false;
644#endif
645
646 if (!HasError)
647 new (getStorage()) storage_type(std::move(*Other.getStorage()));
648 else
649 new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage()));
650 }
651
652 template <class OtherT> void moveAssign(Expected<OtherT> &&Other) {
653 assertIsChecked();
654
655 if (compareThisIfSameType(*this, Other))
656 return;
657
658 this->~Expected();
659 new (this) Expected(std::move(Other));
660 }
661
662 pointer toPointer(pointer Val) { return Val; }
663
664 const_pointer toPointer(const_pointer Val) const { return Val; }
665
666 pointer toPointer(wrap *Val) { return &Val->get(); }
667
668 const_pointer toPointer(const wrap *Val) const { return &Val->get(); }
669
670 storage_type *getStorage() {
671 assert(!HasError && "Cannot get value when an error exists!")(static_cast <bool> (!HasError && "Cannot get value when an error exists!"
) ? void (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "llvm/include/llvm/Support/Error.h", 671, __extension__ __PRETTY_FUNCTION__
))
;
672 return reinterpret_cast<storage_type *>(&TStorage);
673 }
674
675 const storage_type *getStorage() const {
676 assert(!HasError && "Cannot get value when an error exists!")(static_cast <bool> (!HasError && "Cannot get value when an error exists!"
) ? void (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "llvm/include/llvm/Support/Error.h", 676, __extension__ __PRETTY_FUNCTION__
))
;
677 return reinterpret_cast<const storage_type *>(&TStorage);
678 }
679
680 error_type *getErrorStorage() {
681 assert(HasError && "Cannot get error when a value exists!")(static_cast <bool> (HasError && "Cannot get error when a value exists!"
) ? void (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "llvm/include/llvm/Support/Error.h", 681, __extension__ __PRETTY_FUNCTION__
))
;
682 return reinterpret_cast<error_type *>(&ErrorStorage);
683 }
684
685 const error_type *getErrorStorage() const {
686 assert(HasError && "Cannot get error when a value exists!")(static_cast <bool> (HasError && "Cannot get error when a value exists!"
) ? void (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "llvm/include/llvm/Support/Error.h", 686, __extension__ __PRETTY_FUNCTION__
))
;
687 return reinterpret_cast<const error_type *>(&ErrorStorage);
688 }
689
690 // Used by ExpectedAsOutParameter to reset the checked flag.
691 void setUnchecked() {
692#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
693 Unchecked = true;
694#endif
695 }
696
697#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
698 [[noreturn]] LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline)) void fatalUncheckedExpected() const {
699 dbgs() << "Expected<T> must be checked before access or destruction.\n";
700 if (HasError) {
701 dbgs() << "Unchecked Expected<T> contained error:\n";
702 (*getErrorStorage())->log(dbgs());
703 } else
704 dbgs() << "Expected<T> value was in success state. (Note: Expected<T> "
705 "values in success mode must still be checked prior to being "
706 "destroyed).\n";
707 abort();
708 }
709#endif
710
711 void assertIsChecked() const {
712#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
713 if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false))
714 fatalUncheckedExpected();
715#endif
716 }
717
718 union {
719 AlignedCharArrayUnion<storage_type> TStorage;
720 AlignedCharArrayUnion<error_type> ErrorStorage;
721 };
722 bool HasError : 1;
723#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
724 bool Unchecked : 1;
725#endif
726};
727
728/// Report a serious error, calling any installed error handler. See
729/// ErrorHandling.h.
730[[noreturn]] void report_fatal_error(Error Err, bool gen_crash_diag = true);
731
732/// Report a fatal error if Err is a failure value.
733///
734/// This function can be used to wrap calls to fallible functions ONLY when it
735/// is known that the Error will always be a success value. E.g.
736///
737/// @code{.cpp}
738/// // foo only attempts the fallible operation if DoFallibleOperation is
739/// // true. If DoFallibleOperation is false then foo always returns
740/// // Error::success().
741/// Error foo(bool DoFallibleOperation);
742///
743/// cantFail(foo(false));
744/// @endcode
745inline void cantFail(Error Err, const char *Msg = nullptr) {
746 if (Err) {
747 if (!Msg)
748 Msg = "Failure value returned from cantFail wrapped call";
749#ifndef NDEBUG
750 std::string Str;
751 raw_string_ostream OS(Str);
752 OS << Msg << "\n" << Err;
753 Msg = OS.str().c_str();
754#endif
755 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "llvm/include/llvm/Support/Error.h"
, 755)
;
756 }
757}
758
759/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
760/// returns the contained value.
761///
762/// This function can be used to wrap calls to fallible functions ONLY when it
763/// is known that the Error will always be a success value. E.g.
764///
765/// @code{.cpp}
766/// // foo only attempts the fallible operation if DoFallibleOperation is
767/// // true. If DoFallibleOperation is false then foo always returns an int.
768/// Expected<int> foo(bool DoFallibleOperation);
769///
770/// int X = cantFail(foo(false));
771/// @endcode
772template <typename T>
773T cantFail(Expected<T> ValOrErr, const char *Msg = nullptr) {
774 if (ValOrErr)
775 return std::move(*ValOrErr);
776 else {
777 if (!Msg)
778 Msg = "Failure value returned from cantFail wrapped call";
779#ifndef NDEBUG
780 std::string Str;
781 raw_string_ostream OS(Str);
782 auto E = ValOrErr.takeError();
783 OS << Msg << "\n" << E;
784 Msg = OS.str().c_str();
785#endif
786 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "llvm/include/llvm/Support/Error.h"
, 786)
;
787 }
788}
789
790/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
791/// returns the contained reference.
792///
793/// This function can be used to wrap calls to fallible functions ONLY when it
794/// is known that the Error will always be a success value. E.g.
795///
796/// @code{.cpp}
797/// // foo only attempts the fallible operation if DoFallibleOperation is
798/// // true. If DoFallibleOperation is false then foo always returns a Bar&.
799/// Expected<Bar&> foo(bool DoFallibleOperation);
800///
801/// Bar &X = cantFail(foo(false));
802/// @endcode
803template <typename T>
804T& cantFail(Expected<T&> ValOrErr, const char *Msg = nullptr) {
805 if (ValOrErr)
806 return *ValOrErr;
807 else {
808 if (!Msg)
809 Msg = "Failure value returned from cantFail wrapped call";
810#ifndef NDEBUG
811 std::string Str;
812 raw_string_ostream OS(Str);
813 auto E = ValOrErr.takeError();
814 OS << Msg << "\n" << E;
815 Msg = OS.str().c_str();
816#endif
817 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "llvm/include/llvm/Support/Error.h"
, 817)
;
818 }
819}
820
821/// Helper for testing applicability of, and applying, handlers for
822/// ErrorInfo types.
823template <typename HandlerT>
824class ErrorHandlerTraits
825 : public ErrorHandlerTraits<decltype(
826 &std::remove_reference<HandlerT>::type::operator())> {};
827
828// Specialization functions of the form 'Error (const ErrT&)'.
829template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> {
830public:
831 static bool appliesTo(const ErrorInfoBase &E) {
832 return E.template isA<ErrT>();
833 }
834
835 template <typename HandlerT>
836 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
837 assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "llvm/include/llvm/Support/Error.h", 837, __extension__ __PRETTY_FUNCTION__
))
;
838 return H(static_cast<ErrT &>(*E));
839 }
840};
841
842// Specialization functions of the form 'void (const ErrT&)'.
843template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> {
844public:
845 static bool appliesTo(const ErrorInfoBase &E) {
846 return E.template isA<ErrT>();
847 }
848
849 template <typename HandlerT>
850 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
851 assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "llvm/include/llvm/Support/Error.h", 851, __extension__ __PRETTY_FUNCTION__
))
;
852 H(static_cast<ErrT &>(*E));
853 return Error::success();
854 }
855};
856
857/// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'.
858template <typename ErrT>
859class ErrorHandlerTraits<Error (&)(std::unique_ptr<ErrT>)> {
860public:
861 static bool appliesTo(const ErrorInfoBase &E) {
862 return E.template isA<ErrT>();
863 }
864
865 template <typename HandlerT>
866 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
867 assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "llvm/include/llvm/Support/Error.h", 867, __extension__ __PRETTY_FUNCTION__
))
;
868 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
869 return H(std::move(SubE));
870 }
871};
872
873/// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'.
874template <typename ErrT>
875class ErrorHandlerTraits<void (&)(std::unique_ptr<ErrT>)> {
876public:
877 static bool appliesTo(const ErrorInfoBase &E) {
878 return E.template isA<ErrT>();
879 }
880
881 template <typename HandlerT>
882 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
883 assert(appliesTo(*E) && "Applying incorrect handler")(static_cast <bool> (appliesTo(*E) && "Applying incorrect handler"
) ? void (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "llvm/include/llvm/Support/Error.h", 883, __extension__ __PRETTY_FUNCTION__
))
;
884 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
885 H(std::move(SubE));
886 return Error::success();
887 }
888};
889
890// Specialization for member functions of the form 'RetT (const ErrT&)'.
891template <typename C, typename RetT, typename ErrT>
892class ErrorHandlerTraits<RetT (C::*)(ErrT &)>
893 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
894
895// Specialization for member functions of the form 'RetT (const ErrT&) const'.
896template <typename C, typename RetT, typename ErrT>
897class ErrorHandlerTraits<RetT (C::*)(ErrT &) const>
898 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
899
900// Specialization for member functions of the form 'RetT (const ErrT&)'.
901template <typename C, typename RetT, typename ErrT>
902class ErrorHandlerTraits<RetT (C::*)(const ErrT &)>
903 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
904
905// Specialization for member functions of the form 'RetT (const ErrT&) const'.
906template <typename C, typename RetT, typename ErrT>
907class ErrorHandlerTraits<RetT (C::*)(const ErrT &) const>
908 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
909
910/// Specialization for member functions of the form
911/// 'RetT (std::unique_ptr<ErrT>)'.
912template <typename C, typename RetT, typename ErrT>
913class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>)>
914 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
915
916/// Specialization for member functions of the form
917/// 'RetT (std::unique_ptr<ErrT>) const'.
918template <typename C, typename RetT, typename ErrT>
919class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const>
920 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
921
922inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) {
923 return Error(std::move(Payload));
924}
925
926template <typename HandlerT, typename... HandlerTs>
927Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload,
928 HandlerT &&Handler, HandlerTs &&... Handlers) {
929 if (ErrorHandlerTraits<HandlerT>::appliesTo(*Payload))
930 return ErrorHandlerTraits<HandlerT>::apply(std::forward<HandlerT>(Handler),
931 std::move(Payload));
932 return handleErrorImpl(std::move(Payload),
933 std::forward<HandlerTs>(Handlers)...);
934}
935
936/// Pass the ErrorInfo(s) contained in E to their respective handlers. Any
937/// unhandled errors (or Errors returned by handlers) are re-concatenated and
938/// returned.
939/// Because this function returns an error, its result must also be checked
940/// or returned. If you intend to handle all errors use handleAllErrors
941/// (which returns void, and will abort() on unhandled errors) instead.
942template <typename... HandlerTs>
943Error handleErrors(Error E, HandlerTs &&... Hs) {
944 if (!E)
945 return Error::success();
946
947 std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
948
949 if (Payload->isA<ErrorList>()) {
950 ErrorList &List = static_cast<ErrorList &>(*Payload);
951 Error R;
952 for (auto &P : List.Payloads)
953 R = ErrorList::join(
954 std::move(R),
955 handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...));
956 return R;
957 }
958
959 return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...);
960}
961
962/// Behaves the same as handleErrors, except that by contract all errors
963/// *must* be handled by the given handlers (i.e. there must be no remaining
964/// errors after running the handlers, or llvm_unreachable is called).
965template <typename... HandlerTs>
966void handleAllErrors(Error E, HandlerTs &&... Handlers) {
967 cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...));
968}
969
970/// Check that E is a non-error, then drop it.
971/// If E is an error, llvm_unreachable will be called.
972inline void handleAllErrors(Error E) {
973 cantFail(std::move(E));
974}
975
976/// Handle any errors (if present) in an Expected<T>, then try a recovery path.
977///
978/// If the incoming value is a success value it is returned unmodified. If it
979/// is a failure value then it the contained error is passed to handleErrors.
980/// If handleErrors is able to handle the error then the RecoveryPath functor
981/// is called to supply the final result. If handleErrors is not able to
982/// handle all errors then the unhandled errors are returned.
983///
984/// This utility enables the follow pattern:
985///
986/// @code{.cpp}
987/// enum FooStrategy { Aggressive, Conservative };
988/// Expected<Foo> foo(FooStrategy S);
989///
990/// auto ResultOrErr =
991/// handleExpected(
992/// foo(Aggressive),
993/// []() { return foo(Conservative); },
994/// [](AggressiveStrategyError&) {
995/// // Implicitly conusme this - we'll recover by using a conservative
996/// // strategy.
997/// });
998///
999/// @endcode
1000template <typename T, typename RecoveryFtor, typename... HandlerTs>
1001Expected<T> handleExpected(Expected<T> ValOrErr, RecoveryFtor &&RecoveryPath,
1002 HandlerTs &&... Handlers) {
1003 if (ValOrErr)
1004 return ValOrErr;
1005
1006 if (auto Err = handleErrors(ValOrErr.takeError(),
1007 std::forward<HandlerTs>(Handlers)...))
1008 return std::move(Err);
1009
1010 return RecoveryPath();
1011}
1012
1013/// Log all errors (if any) in E to OS. If there are any errors, ErrorBanner
1014/// will be printed before the first one is logged. A newline will be printed
1015/// after each error.
1016///
1017/// This function is compatible with the helpers from Support/WithColor.h. You
1018/// can pass any of them as the OS. Please consider using them instead of
1019/// including 'error: ' in the ErrorBanner.
1020///
1021/// This is useful in the base level of your program to allow clean termination
1022/// (allowing clean deallocation of resources, etc.), while reporting error
1023/// information to the user.
1024void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner = {});
1025
1026/// Write all error messages (if any) in E to a string. The newline character
1027/// is used to separate error messages.
1028inline std::string toString(Error E) {
1029 SmallVector<std::string, 2> Errors;
1030 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
1031 Errors.push_back(EI.message());
1032 });
1033 return join(Errors.begin(), Errors.end(), "\n");
1034}
1035
1036/// Consume a Error without doing anything. This method should be used
1037/// only where an error can be considered a reasonable and expected return
1038/// value.
1039///
1040/// Uses of this method are potentially indicative of design problems: If it's
1041/// legitimate to do nothing while processing an "error", the error-producer
1042/// might be more clearly refactored to return an Optional<T>.
1043inline void consumeError(Error Err) {
1044 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
1045}
1046
1047/// Convert an Expected to an Optional without doing anything. This method
1048/// should be used only where an error can be considered a reasonable and
1049/// expected return value.
1050///
1051/// Uses of this method are potentially indicative of problems: perhaps the
1052/// error should be propagated further, or the error-producer should just
1053/// return an Optional in the first place.
1054template <typename T> Optional<T> expectedToOptional(Expected<T> &&E) {
1055 if (E)
1056 return std::move(*E);
1057 consumeError(E.takeError());
1058 return None;
1059}
1060
1061/// Helper for converting an Error to a bool.
1062///
1063/// This method returns true if Err is in an error state, or false if it is
1064/// in a success state. Puts Err in a checked state in both cases (unlike
1065/// Error::operator bool(), which only does this for success states).
1066inline bool errorToBool(Error Err) {
1067 bool IsError = static_cast<bool>(Err);
1068 if (IsError)
1069 consumeError(std::move(Err));
1070 return IsError;
1071}
1072
1073/// Helper for Errors used as out-parameters.
1074///
1075/// This helper is for use with the Error-as-out-parameter idiom, where an error
1076/// is passed to a function or method by reference, rather than being returned.
1077/// In such cases it is helpful to set the checked bit on entry to the function
1078/// so that the error can be written to (unchecked Errors abort on assignment)
1079/// and clear the checked bit on exit so that clients cannot accidentally forget
1080/// to check the result. This helper performs these actions automatically using
1081/// RAII:
1082///
1083/// @code{.cpp}
1084/// Result foo(Error &Err) {
1085/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1086/// // <body of foo>
1087/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1088/// }
1089/// @endcode
1090///
1091/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1092/// used with optional Errors (Error pointers that are allowed to be null). If
1093/// ErrorAsOutParameter took an Error reference, an instance would have to be
1094/// created inside every condition that verified that Error was non-null. By
1095/// taking an Error pointer we can just create one instance at the top of the
1096/// function.
1097class ErrorAsOutParameter {
1098public:
1099 ErrorAsOutParameter(Error *Err) : Err(Err) {
1100 // Raise the checked bit if Err is success.
1101 if (Err)
1102 (void)!!*Err;
1103 }
1104
1105 ~ErrorAsOutParameter() {
1106 // Clear the checked bit.
1107 if (Err && !*Err)
1108 *Err = Error::success();
1109 }
1110
1111private:
1112 Error *Err;
1113};
1114
1115/// Helper for Expected<T>s used as out-parameters.
1116///
1117/// See ErrorAsOutParameter.
1118template <typename T>
1119class ExpectedAsOutParameter {
1120public:
1121 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1122 : ValOrErr(ValOrErr) {
1123 if (ValOrErr)
1124 (void)!!*ValOrErr;
1125 }
1126
1127 ~ExpectedAsOutParameter() {
1128 if (ValOrErr)
1129 ValOrErr->setUnchecked();
1130 }
1131
1132private:
1133 Expected<T> *ValOrErr;
1134};
1135
1136/// This class wraps a std::error_code in a Error.
1137///
1138/// This is useful if you're writing an interface that returns a Error
1139/// (or Expected) and you want to call code that still returns
1140/// std::error_codes.
1141class ECError : public ErrorInfo<ECError> {
1142 friend Error errorCodeToError(std::error_code);
1143
1144 virtual void anchor() override;
1145
1146public:
1147 void setErrorCode(std::error_code EC) { this->EC = EC; }
1148 std::error_code convertToErrorCode() const override { return EC; }
1149 void log(raw_ostream &OS) const override { OS << EC.message(); }
1150
1151 // Used by ErrorInfo::classID.
1152 static char ID;
1153
1154protected:
1155 ECError() = default;
1156 ECError(std::error_code EC) : EC(EC) {}
1157
1158 std::error_code EC;
1159};
1160
1161/// The value returned by this function can be returned from convertToErrorCode
1162/// for Error values where no sensible translation to std::error_code exists.
1163/// It should only be used in this situation, and should never be used where a
1164/// sensible conversion to std::error_code is available, as attempts to convert
1165/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1166/// error to try to convert such a value).
1167std::error_code inconvertibleErrorCode();
1168
1169/// Helper for converting an std::error_code to a Error.
1170Error errorCodeToError(std::error_code EC);
1171
1172/// Helper for converting an ECError to a std::error_code.
1173///
1174/// This method requires that Err be Error() or an ECError, otherwise it
1175/// will trigger a call to abort().
1176std::error_code errorToErrorCode(Error Err);
1177
1178/// Convert an ErrorOr<T> to an Expected<T>.
1179template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1180 if (auto EC = EO.getError())
1181 return errorCodeToError(EC);
1182 return std::move(*EO);
1183}
1184
1185/// Convert an Expected<T> to an ErrorOr<T>.
1186template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1187 if (auto Err = E.takeError())
1188 return errorToErrorCode(std::move(Err));
1189 return std::move(*E);
1190}
1191
1192/// This class wraps a string in an Error.
1193///
1194/// StringError is useful in cases where the client is not expected to be able
1195/// to consume the specific error message programmatically (for example, if the
1196/// error message is to be presented to the user).
1197///
1198/// StringError can also be used when additional information is to be printed
1199/// along with a error_code message. Depending on the constructor called, this
1200/// class can either display:
1201/// 1. the error_code message (ECError behavior)
1202/// 2. a string
1203/// 3. the error_code message and a string
1204///
1205/// These behaviors are useful when subtyping is required; for example, when a
1206/// specific library needs an explicit error type. In the example below,
1207/// PDBError is derived from StringError:
1208///
1209/// @code{.cpp}
1210/// Expected<int> foo() {
1211/// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1212/// "Additional information");
1213/// }
1214/// @endcode
1215///
1216class StringError : public ErrorInfo<StringError> {
1217public:
1218 static char ID;
1219
1220 // Prints EC + S and converts to EC
1221 StringError(std::error_code EC, const Twine &S = Twine());
1222
1223 // Prints S and converts to EC
1224 StringError(const Twine &S, std::error_code EC);
1225
1226 void log(raw_ostream &OS) const override;
1227 std::error_code convertToErrorCode() const override;
1228
1229 const std::string &getMessage() const { return Msg; }
1230
1231private:
1232 std::string Msg;
1233 std::error_code EC;
1234 const bool PrintMsgOnly = false;
1235};
1236
1237/// Create formatted StringError object.
1238template <typename... Ts>
1239inline Error createStringError(std::error_code EC, char const *Fmt,
1240 const Ts &... Vals) {
1241 std::string Buffer;
1242 raw_string_ostream Stream(Buffer);
1243 Stream << format(Fmt, Vals...);
1244 return make_error<StringError>(Stream.str(), EC);
1245}
1246
1247Error createStringError(std::error_code EC, char const *Msg);
1248
1249inline Error createStringError(std::error_code EC, const Twine &S) {
1250 return createStringError(EC, S.str().c_str());
1251}
1252
1253template <typename... Ts>
1254inline Error createStringError(std::errc EC, char const *Fmt,
1255 const Ts &... Vals) {
1256 return createStringError(std::make_error_code(EC), Fmt, Vals...);
1257}
1258
1259/// This class wraps a filename and another Error.
1260///
1261/// In some cases, an error needs to live along a 'source' name, in order to
1262/// show more detailed information to the user.
1263class FileError final : public ErrorInfo<FileError> {
1264
1265 friend Error createFileError(const Twine &, Error);
1266 friend Error createFileError(const Twine &, size_t, Error);
1267
1268public:
1269 void log(raw_ostream &OS) const override {
1270 assert(Err && "Trying to log after takeError().")(static_cast <bool> (Err && "Trying to log after takeError()."
) ? void (0) : __assert_fail ("Err && \"Trying to log after takeError().\""
, "llvm/include/llvm/Support/Error.h", 1270, __extension__ __PRETTY_FUNCTION__
))
;
1271 OS << "'" << FileName << "': ";
1272 if (Line.hasValue())
1273 OS << "line " << Line.getValue() << ": ";
1274 Err->log(OS);
1275 }
1276
1277 std::string messageWithoutFileInfo() const {
1278 std::string Msg;
1279 raw_string_ostream OS(Msg);
1280 Err->log(OS);
1281 return OS.str();
1282 }
1283
1284 StringRef getFileName() { return FileName; }
1285
1286 Error takeError() { return Error(std::move(Err)); }
1287
1288 std::error_code convertToErrorCode() const override;
1289
1290 // Used by ErrorInfo::classID.
1291 static char ID;
1292
1293private:
1294 FileError(const Twine &F, Optional<size_t> LineNum,
1295 std::unique_ptr<ErrorInfoBase> E) {
1296 assert(E && "Cannot create FileError from Error success value.")(static_cast <bool> (E && "Cannot create FileError from Error success value."
) ? void (0) : __assert_fail ("E && \"Cannot create FileError from Error success value.\""
, "llvm/include/llvm/Support/Error.h", 1296, __extension__ __PRETTY_FUNCTION__
))
;
1297 FileName = F.str();
1298 Err = std::move(E);
1299 Line = std::move(LineNum);
1300 }
1301
1302 static Error build(const Twine &F, Optional<size_t> Line, Error E) {
1303 std::unique_ptr<ErrorInfoBase> Payload;
1304 handleAllErrors(std::move(E),
1305 [&](std::unique_ptr<ErrorInfoBase> EIB) -> Error {
1306 Payload = std::move(EIB);
1307 return Error::success();
1308 });
1309 return Error(
1310 std::unique_ptr<FileError>(new FileError(F, Line, std::move(Payload))));
1311 }
1312
1313 std::string FileName;
1314 Optional<size_t> Line;
1315 std::unique_ptr<ErrorInfoBase> Err;
1316};
1317
1318/// Concatenate a source file path and/or name with an Error. The resulting
1319/// Error is unchecked.
1320inline Error createFileError(const Twine &F, Error E) {
1321 return FileError::build(F, Optional<size_t>(), std::move(E));
1322}
1323
1324/// Concatenate a source file path and/or name with line number and an Error.
1325/// The resulting Error is unchecked.
1326inline Error createFileError(const Twine &F, size_t Line, Error E) {
1327 return FileError::build(F, Optional<size_t>(Line), std::move(E));
1328}
1329
1330/// Concatenate a source file path and/or name with a std::error_code
1331/// to form an Error object.
1332inline Error createFileError(const Twine &F, std::error_code EC) {
1333 return createFileError(F, errorCodeToError(EC));
1334}
1335
1336/// Concatenate a source file path and/or name with line number and
1337/// std::error_code to form an Error object.
1338inline Error createFileError(const Twine &F, size_t Line, std::error_code EC) {
1339 return createFileError(F, Line, errorCodeToError(EC));
1340}
1341
1342Error createFileError(const Twine &F, ErrorSuccess) = delete;
1343
1344/// Helper for check-and-exit error handling.
1345///
1346/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1347///
1348class ExitOnError {
1349public:
1350 /// Create an error on exit helper.
1351 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1352 : Banner(std::move(Banner)),
1353 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1354
1355 /// Set the banner string for any errors caught by operator().
1356 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1357
1358 /// Set the exit-code mapper function.
1359 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1360 this->GetExitCode = std::move(GetExitCode);
1361 }
1362
1363 /// Check Err. If it's in a failure state log the error(s) and exit.
1364 void operator()(Error Err) const { checkError(std::move(Err)); }
1365
1366 /// Check E. If it's in a success state then return the contained value. If
1367 /// it's in a failure state log the error(s) and exit.
1368 template <typename T> T operator()(Expected<T> &&E) const {
1369 checkError(E.takeError());
1370 return std::move(*E);
1371 }
1372
1373 /// Check E. If it's in a success state then return the contained reference. If
1374 /// it's in a failure state log the error(s) and exit.
1375 template <typename T> T& operator()(Expected<T&> &&E) const {
1376 checkError(E.takeError());
1377 return *E;
1378 }
1379
1380private:
1381 void checkError(Error Err) const {
1382 if (Err) {
1383 int ExitCode = GetExitCode(Err);
1384 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1385 exit(ExitCode);
1386 }
1387 }
1388
1389 std::string Banner;
1390 std::function<int(const Error &)> GetExitCode;
1391};
1392
1393/// Conversion from Error to LLVMErrorRef for C error bindings.
1394inline LLVMErrorRef wrap(Error Err) {
1395 return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1396}
1397
1398/// Conversion from LLVMErrorRef to Error for C error bindings.
1399inline Error unwrap(LLVMErrorRef ErrRef) {
1400 return Error(std::unique_ptr<ErrorInfoBase>(
1401 reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1402}
1403
1404} // end namespace llvm
1405
1406#endif // LLVM_SUPPORT_ERROR_H