Bug Summary

File:include/llvm/Support/Error.h
Warning:line 201, column 5
Potential leak of memory pointed to by 'Payload._M_t._M_head_impl'

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 DWARFVerifier.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 -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-8/lib/clang/8.0.0 -D _DEBUG -D _GNU_SOURCE -D __STDC_CONSTANT_MACROS -D __STDC_FORMAT_MACROS -D __STDC_LIMIT_MACROS -I /build/llvm-toolchain-snapshot-8~svn350071/build-llvm/lib/DebugInfo/DWARF -I /build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF -I /build/llvm-toolchain-snapshot-8~svn350071/build-llvm/include -I /build/llvm-toolchain-snapshot-8~svn350071/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/include/clang/8.0.0/include/ -internal-isystem /usr/local/include -internal-isystem /usr/lib/llvm-8/lib/clang/8.0.0/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-8~svn350071/build-llvm/lib/DebugInfo/DWARF -fdebug-prefix-map=/build/llvm-toolchain-snapshot-8~svn350071=. -ferror-limit 19 -fmessage-length 0 -fvisibility-inlines-hidden -stack-protector 2 -fobjc-runtime=gcc -fdiagnostics-show-option -vectorize-loops -vectorize-slp -analyzer-output=html -analyzer-config stable-report-filename=true -o /tmp/scan-build-2018-12-27-042839-1215-1 -x c++ /build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF/DWARFVerifier.cpp -faddrsig

/build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF/DWARFVerifier.cpp

1//===- DWARFVerifier.cpp --------------------------------------------------===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9#include "llvm/DebugInfo/DWARF/DWARFVerifier.h"
10#include "llvm/ADT/SmallSet.h"
11#include "llvm/DebugInfo/DWARF/DWARFCompileUnit.h"
12#include "llvm/DebugInfo/DWARF/DWARFContext.h"
13#include "llvm/DebugInfo/DWARF/DWARFDebugLine.h"
14#include "llvm/DebugInfo/DWARF/DWARFDie.h"
15#include "llvm/DebugInfo/DWARF/DWARFExpression.h"
16#include "llvm/DebugInfo/DWARF/DWARFFormValue.h"
17#include "llvm/DebugInfo/DWARF/DWARFSection.h"
18#include "llvm/Support/DJB.h"
19#include "llvm/Support/FormatVariadic.h"
20#include "llvm/Support/WithColor.h"
21#include "llvm/Support/raw_ostream.h"
22#include <map>
23#include <set>
24#include <vector>
25
26using namespace llvm;
27using namespace dwarf;
28using namespace object;
29
30DWARFVerifier::DieRangeInfo::address_range_iterator
31DWARFVerifier::DieRangeInfo::insert(const DWARFAddressRange &R) {
32 auto Begin = Ranges.begin();
33 auto End = Ranges.end();
34 auto Pos = std::lower_bound(Begin, End, R);
35
36 if (Pos != End) {
37 if (Pos->intersects(R))
38 return Pos;
39 if (Pos != Begin) {
40 auto Iter = Pos - 1;
41 if (Iter->intersects(R))
42 return Iter;
43 }
44 }
45
46 Ranges.insert(Pos, R);
47 return Ranges.end();
48}
49
50DWARFVerifier::DieRangeInfo::die_range_info_iterator
51DWARFVerifier::DieRangeInfo::insert(const DieRangeInfo &RI) {
52 auto End = Children.end();
53 auto Iter = Children.begin();
54 while (Iter != End) {
55 if (Iter->intersects(RI))
56 return Iter;
57 ++Iter;
58 }
59 Children.insert(RI);
60 return Children.end();
61}
62
63bool DWARFVerifier::DieRangeInfo::contains(const DieRangeInfo &RHS) const {
64 // Both list of ranges are sorted so we can make this fast.
65
66 if (Ranges.empty() || RHS.Ranges.empty())
67 return false;
68
69 // Since the ranges are sorted we can advance where we start searching with
70 // this object's ranges as we traverse RHS.Ranges.
71 auto End = Ranges.end();
72 auto Iter = findRange(RHS.Ranges.front());
73
74 // Now linearly walk the ranges in this object and see if they contain each
75 // ranges from RHS.Ranges.
76 for (const auto &R : RHS.Ranges) {
77 while (Iter != End) {
78 if (Iter->contains(R))
79 break;
80 ++Iter;
81 }
82 if (Iter == End)
83 return false;
84 }
85 return true;
86}
87
88bool DWARFVerifier::DieRangeInfo::intersects(const DieRangeInfo &RHS) const {
89 if (Ranges.empty() || RHS.Ranges.empty())
90 return false;
91
92 auto End = Ranges.end();
93 auto Iter = findRange(RHS.Ranges.front());
94 for (const auto &R : RHS.Ranges) {
95 if (Iter == End)
96 return false;
97 if (R.HighPC <= Iter->LowPC)
98 continue;
99 while (Iter != End) {
100 if (Iter->intersects(R))
101 return true;
102 ++Iter;
103 }
104 }
105
106 return false;
107}
108
109bool DWARFVerifier::verifyUnitHeader(const DWARFDataExtractor DebugInfoData,
110 uint32_t *Offset, unsigned UnitIndex,
111 uint8_t &UnitType, bool &isUnitDWARF64) {
112 uint32_t AbbrOffset, Length;
113 uint8_t AddrSize = 0;
114 uint16_t Version;
115 bool Success = true;
116
117 bool ValidLength = false;
118 bool ValidVersion = false;
119 bool ValidAddrSize = false;
120 bool ValidType = true;
121 bool ValidAbbrevOffset = true;
122
123 uint32_t OffsetStart = *Offset;
124 Length = DebugInfoData.getU32(Offset);
125 if (Length == UINT32_MAX(4294967295U)) {
126 isUnitDWARF64 = true;
127 OS << format(
128 "Unit[%d] is in 64-bit DWARF format; cannot verify from this point.\n",
129 UnitIndex);
130 return false;
131 }
132 Version = DebugInfoData.getU16(Offset);
133
134 if (Version >= 5) {
135 UnitType = DebugInfoData.getU8(Offset);
136 AddrSize = DebugInfoData.getU8(Offset);
137 AbbrOffset = DebugInfoData.getU32(Offset);
138 ValidType = dwarf::isUnitType(UnitType);
139 } else {
140 UnitType = 0;
141 AbbrOffset = DebugInfoData.getU32(Offset);
142 AddrSize = DebugInfoData.getU8(Offset);
143 }
144
145 if (!DCtx.getDebugAbbrev()->getAbbreviationDeclarationSet(AbbrOffset))
146 ValidAbbrevOffset = false;
147
148 ValidLength = DebugInfoData.isValidOffset(OffsetStart + Length + 3);
149 ValidVersion = DWARFContext::isSupportedVersion(Version);
150 ValidAddrSize = AddrSize == 4 || AddrSize == 8;
151 if (!ValidLength || !ValidVersion || !ValidAddrSize || !ValidAbbrevOffset ||
152 !ValidType) {
153 Success = false;
154 error() << format("Units[%d] - start offset: 0x%08x \n", UnitIndex,
155 OffsetStart);
156 if (!ValidLength)
157 note() << "The length for this unit is too "
158 "large for the .debug_info provided.\n";
159 if (!ValidVersion)
160 note() << "The 16 bit unit header version is not valid.\n";
161 if (!ValidType)
162 note() << "The unit type encoding is not valid.\n";
163 if (!ValidAbbrevOffset)
164 note() << "The offset into the .debug_abbrev section is "
165 "not valid.\n";
166 if (!ValidAddrSize)
167 note() << "The address size is unsupported.\n";
168 }
169 *Offset = OffsetStart + Length + 4;
170 return Success;
171}
172
173unsigned DWARFVerifier::verifyUnitContents(DWARFUnit &Unit) {
174 unsigned NumUnitErrors = 0;
175 unsigned NumDies = Unit.getNumDIEs();
176 for (unsigned I = 0; I < NumDies; ++I) {
6
Assuming 'I' is >= 'NumDies'
7
Loop condition is false. Execution continues on line 200
177 auto Die = Unit.getDIEAtIndex(I);
178
179 if (Die.getTag() == DW_TAG_null)
180 continue;
181
182 bool HasTypeAttr = false;
183 for (auto AttrValue : Die.attributes()) {
184 NumUnitErrors += verifyDebugInfoAttribute(Die, AttrValue);
185 NumUnitErrors += verifyDebugInfoForm(Die, AttrValue);
186 HasTypeAttr |= (AttrValue.Attr == DW_AT_type);
187 }
188
189 if (!HasTypeAttr && (Die.getTag() == DW_TAG_formal_parameter ||
190 Die.getTag() == DW_TAG_variable ||
191 Die.getTag() == DW_TAG_array_type)) {
192 error() << "DIE with tag " << TagString(Die.getTag())
193 << " is missing type attribute:\n";
194 dump(Die) << '\n';
195 NumUnitErrors++;
196 }
197 NumUnitErrors += verifyDebugInfoCallSite(Die);
198 }
199
200 DWARFDie Die = Unit.getUnitDIE(/* ExtractUnitDIEOnly = */ false);
201 if (!Die) {
8
Assuming the condition is false
9
Taking false branch
202 error() << "Compilation unit without DIE.\n";
203 NumUnitErrors++;
204 return NumUnitErrors;
205 }
206
207 if (!dwarf::isUnitType(Die.getTag())) {
10
Taking true branch
208 error() << "Compilation unit root DIE is not a unit DIE: "
209 << dwarf::TagString(Die.getTag()) << ".\n";
210 NumUnitErrors++;
211 }
212
213 uint8_t UnitType = Unit.getUnitType();
214 if (!DWARFUnit::isMatchingUnitTypeAndTag(UnitType, Die.getTag())) {
11
Taking true branch
215 error() << "Compilation unit type (" << dwarf::UnitTypeString(UnitType)
216 << ") and root DIE (" << dwarf::TagString(Die.getTag())
217 << ") do not match.\n";
218 NumUnitErrors++;
219 }
220
221 DieRangeInfo RI;
222 NumUnitErrors += verifyDieRanges(Die, RI);
12
Calling 'DWARFVerifier::verifyDieRanges'
223
224 return NumUnitErrors;
225}
226
227unsigned DWARFVerifier::verifyDebugInfoCallSite(const DWARFDie &Die) {
228 if (Die.getTag() != DW_TAG_call_site)
229 return 0;
230
231 DWARFDie Curr = Die.getParent();
232 for (; Curr.isValid() && !Curr.isSubprogramDIE(); Curr = Die.getParent()) {
233 if (Curr.getTag() == DW_TAG_inlined_subroutine) {
234 error() << "Call site entry nested within inlined subroutine:";
235 Curr.dump(OS);
236 return 1;
237 }
238 }
239
240 if (!Curr.isValid()) {
241 error() << "Call site entry not nested within a valid subprogram:";
242 Die.dump(OS);
243 return 1;
244 }
245
246 Optional<DWARFFormValue> CallAttr =
247 Curr.find({DW_AT_call_all_calls, DW_AT_call_all_source_calls,
248 DW_AT_call_all_tail_calls});
249 if (!CallAttr) {
250 error() << "Subprogram with call site entry has no DW_AT_call attribute:";
251 Curr.dump(OS);
252 Die.dump(OS, /*indent*/ 1);
253 return 1;
254 }
255
256 return 0;
257}
258
259unsigned DWARFVerifier::verifyAbbrevSection(const DWARFDebugAbbrev *Abbrev) {
260 unsigned NumErrors = 0;
261 if (Abbrev) {
262 const DWARFAbbreviationDeclarationSet *AbbrDecls =
263 Abbrev->getAbbreviationDeclarationSet(0);
264 for (auto AbbrDecl : *AbbrDecls) {
265 SmallDenseSet<uint16_t> AttributeSet;
266 for (auto Attribute : AbbrDecl.attributes()) {
267 auto Result = AttributeSet.insert(Attribute.Attr);
268 if (!Result.second) {
269 error() << "Abbreviation declaration contains multiple "
270 << AttributeString(Attribute.Attr) << " attributes.\n";
271 AbbrDecl.dump(OS);
272 ++NumErrors;
273 }
274 }
275 }
276 }
277 return NumErrors;
278}
279
280bool DWARFVerifier::handleDebugAbbrev() {
281 OS << "Verifying .debug_abbrev...\n";
282
283 const DWARFObject &DObj = DCtx.getDWARFObj();
284 bool noDebugAbbrev = DObj.getAbbrevSection().empty();
285 bool noDebugAbbrevDWO = DObj.getAbbrevDWOSection().empty();
286
287 if (noDebugAbbrev && noDebugAbbrevDWO) {
288 return true;
289 }
290
291 unsigned NumErrors = 0;
292 if (!noDebugAbbrev)
293 NumErrors += verifyAbbrevSection(DCtx.getDebugAbbrev());
294
295 if (!noDebugAbbrevDWO)
296 NumErrors += verifyAbbrevSection(DCtx.getDebugAbbrevDWO());
297 return NumErrors == 0;
298}
299
300unsigned DWARFVerifier::verifyUnitSection(const DWARFSection &S,
301 DWARFSectionKind SectionKind) {
302 const DWARFObject &DObj = DCtx.getDWARFObj();
303 DWARFDataExtractor DebugInfoData(DObj, S, DCtx.isLittleEndian(), 0);
304 unsigned NumDebugInfoErrors = 0;
305 uint32_t OffsetStart = 0, Offset = 0, UnitIdx = 0;
306 uint8_t UnitType = 0;
307 bool isUnitDWARF64 = false;
308 bool isHeaderChainValid = true;
309 bool hasDIE = DebugInfoData.isValidOffset(Offset);
310 DWARFUnitVector TypeUnitVector;
311 DWARFUnitVector CompileUnitVector;
312 while (hasDIE) {
1
Loop condition is true. Entering loop body
313 OffsetStart = Offset;
314 if (!verifyUnitHeader(DebugInfoData, &Offset, UnitIdx, UnitType,
2
Taking false branch
315 isUnitDWARF64)) {
316 isHeaderChainValid = false;
317 if (isUnitDWARF64)
318 break;
319 } else {
320 DWARFUnitHeader Header;
321 Header.extract(DCtx, DebugInfoData, &OffsetStart, SectionKind);
322 DWARFUnit *Unit;
323 switch (UnitType) {
3
Control jumps to 'case 0:' at line 339
324 case dwarf::DW_UT_type:
325 case dwarf::DW_UT_split_type: {
326 Unit = TypeUnitVector.addUnit(llvm::make_unique<DWARFTypeUnit>(
327 DCtx, S, Header, DCtx.getDebugAbbrev(), &DObj.getRangeSection(),
328 &DObj.getLocSection(), DObj.getStringSection(),
329 DObj.getStringOffsetSection(), &DObj.getAppleObjCSection(),
330 DObj.getLineSection(), DCtx.isLittleEndian(), false,
331 TypeUnitVector));
332 break;
333 }
334 case dwarf::DW_UT_skeleton:
335 case dwarf::DW_UT_split_compile:
336 case dwarf::DW_UT_compile:
337 case dwarf::DW_UT_partial:
338 // UnitType = 0 means that we are verifying a compile unit in DWARF v4.
339 case 0: {
340 Unit = CompileUnitVector.addUnit(llvm::make_unique<DWARFCompileUnit>(
341 DCtx, S, Header, DCtx.getDebugAbbrev(), &DObj.getRangeSection(),
342 &DObj.getLocSection(), DObj.getStringSection(),
343 DObj.getStringOffsetSection(), &DObj.getAppleObjCSection(),
344 DObj.getLineSection(), DCtx.isLittleEndian(), false,
345 CompileUnitVector));
346 break;
4
Execution continues on line 350
347 }
348 default: { llvm_unreachable("Invalid UnitType.")::llvm::llvm_unreachable_internal("Invalid UnitType.", "/build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF/DWARFVerifier.cpp"
, 348)
; }
349 }
350 NumDebugInfoErrors += verifyUnitContents(*Unit);
5
Calling 'DWARFVerifier::verifyUnitContents'
351 }
352 hasDIE = DebugInfoData.isValidOffset(Offset);
353 ++UnitIdx;
354 }
355 if (UnitIdx == 0 && !hasDIE) {
356 warn() << "Section is empty.\n";
357 isHeaderChainValid = true;
358 }
359 if (!isHeaderChainValid)
360 ++NumDebugInfoErrors;
361 NumDebugInfoErrors += verifyDebugInfoReferences();
362 return NumDebugInfoErrors;
363}
364
365bool DWARFVerifier::handleDebugInfo() {
366 const DWARFObject &DObj = DCtx.getDWARFObj();
367 unsigned NumErrors = 0;
368
369 OS << "Verifying .debug_info Unit Header Chain...\n";
370 DObj.forEachInfoSections([&](const DWARFSection &S) {
371 NumErrors += verifyUnitSection(S, DW_SECT_INFO);
372 });
373
374 OS << "Verifying .debug_types Unit Header Chain...\n";
375 DObj.forEachTypesSections([&](const DWARFSection &S) {
376 NumErrors += verifyUnitSection(S, DW_SECT_TYPES);
377 });
378 return NumErrors == 0;
379}
380
381unsigned DWARFVerifier::verifyDieRanges(const DWARFDie &Die,
382 DieRangeInfo &ParentRI) {
383 unsigned NumErrors = 0;
384
385 if (!Die.isValid())
13
Assuming the condition is false
14
Taking false branch
386 return NumErrors;
387
388 auto RangesOrError = Die.getAddressRanges();
389 if (!RangesOrError) {
15
Taking true branch
390 // FIXME: Report the error.
391 ++NumErrors;
392 llvm::consumeError(RangesOrError.takeError());
16
Calling 'consumeError'
393 return NumErrors;
394 }
395
396 DWARFAddressRangesVector Ranges = RangesOrError.get();
397 // Build RI for this DIE and check that ranges within this DIE do not
398 // overlap.
399 DieRangeInfo RI(Die);
400
401 // TODO support object files better
402 //
403 // Some object file formats (i.e. non-MachO) support COMDAT. ELF in
404 // particular does so by placing each function into a section. The DWARF data
405 // for the function at that point uses a section relative DW_FORM_addrp for
406 // the DW_AT_low_pc and a DW_FORM_data4 for the offset as the DW_AT_high_pc.
407 // In such a case, when the Die is the CU, the ranges will overlap, and we
408 // will flag valid conflicting ranges as invalid.
409 //
410 // For such targets, we should read the ranges from the CU and partition them
411 // by the section id. The ranges within a particular section should be
412 // disjoint, although the ranges across sections may overlap. We would map
413 // the child die to the entity that it references and the section with which
414 // it is associated. The child would then be checked against the range
415 // information for the associated section.
416 //
417 // For now, simply elide the range verification for the CU DIEs if we are
418 // processing an object file.
419
420 if (!IsObjectFile || IsMachOObject || Die.getTag() != DW_TAG_compile_unit) {
421 for (auto Range : Ranges) {
422 if (!Range.valid()) {
423 ++NumErrors;
424 error() << "Invalid address range " << Range << "\n";
425 continue;
426 }
427
428 // Verify that ranges don't intersect.
429 const auto IntersectingRange = RI.insert(Range);
430 if (IntersectingRange != RI.Ranges.end()) {
431 ++NumErrors;
432 error() << "DIE has overlapping address ranges: " << Range << " and "
433 << *IntersectingRange << "\n";
434 break;
435 }
436 }
437 }
438
439 // Verify that children don't intersect.
440 const auto IntersectingChild = ParentRI.insert(RI);
441 if (IntersectingChild != ParentRI.Children.end()) {
442 ++NumErrors;
443 error() << "DIEs have overlapping address ranges:";
444 dump(Die);
445 dump(IntersectingChild->Die) << '\n';
446 }
447
448 // Verify that ranges are contained within their parent.
449 bool ShouldBeContained = !Ranges.empty() && !ParentRI.Ranges.empty() &&
450 !(Die.getTag() == DW_TAG_subprogram &&
451 ParentRI.Die.getTag() == DW_TAG_subprogram);
452 if (ShouldBeContained && !ParentRI.contains(RI)) {
453 ++NumErrors;
454 error() << "DIE address ranges are not contained in its parent's ranges:";
455 dump(ParentRI.Die);
456 dump(Die, 2) << '\n';
457 }
458
459 // Recursively check children.
460 for (DWARFDie Child : Die)
461 NumErrors += verifyDieRanges(Child, RI);
462
463 return NumErrors;
464}
465
466unsigned DWARFVerifier::verifyDebugInfoAttribute(const DWARFDie &Die,
467 DWARFAttribute &AttrValue) {
468 unsigned NumErrors = 0;
469 auto ReportError = [&](const Twine &TitleMsg) {
470 ++NumErrors;
471 error() << TitleMsg << '\n';
472 dump(Die) << '\n';
473 };
474
475 const DWARFObject &DObj = DCtx.getDWARFObj();
476 const auto Attr = AttrValue.Attr;
477 switch (Attr) {
478 case DW_AT_ranges:
479 // Make sure the offset in the DW_AT_ranges attribute is valid.
480 if (auto SectionOffset = AttrValue.Value.getAsSectionOffset()) {
481 if (*SectionOffset >= DObj.getRangeSection().Data.size())
482 ReportError("DW_AT_ranges offset is beyond .debug_ranges bounds:");
483 break;
484 }
485 ReportError("DIE has invalid DW_AT_ranges encoding:");
486 break;
487 case DW_AT_stmt_list:
488 // Make sure the offset in the DW_AT_stmt_list attribute is valid.
489 if (auto SectionOffset = AttrValue.Value.getAsSectionOffset()) {
490 if (*SectionOffset >= DObj.getLineSection().Data.size())
491 ReportError("DW_AT_stmt_list offset is beyond .debug_line bounds: " +
492 llvm::formatv("{0:x8}", *SectionOffset));
493 break;
494 }
495 ReportError("DIE has invalid DW_AT_stmt_list encoding:");
496 break;
497 case DW_AT_location: {
498 auto VerifyLocationExpr = [&](StringRef D) {
499 DWARFUnit *U = Die.getDwarfUnit();
500 DataExtractor Data(D, DCtx.isLittleEndian(), 0);
501 DWARFExpression Expression(Data, U->getVersion(),
502 U->getAddressByteSize());
503 bool Error = llvm::any_of(Expression, [](DWARFExpression::Operation &Op) {
504 return Op.isError();
505 });
506 if (Error)
507 ReportError("DIE contains invalid DWARF expression:");
508 };
509 if (Optional<ArrayRef<uint8_t>> Expr = AttrValue.Value.getAsBlock()) {
510 // Verify inlined location.
511 VerifyLocationExpr(llvm::toStringRef(*Expr));
512 } else if (auto LocOffset = AttrValue.Value.getAsSectionOffset()) {
513 // Verify location list.
514 if (auto DebugLoc = DCtx.getDebugLoc())
515 if (auto LocList = DebugLoc->getLocationListAtOffset(*LocOffset))
516 for (const auto &Entry : LocList->Entries)
517 VerifyLocationExpr({Entry.Loc.data(), Entry.Loc.size()});
518 }
519 break;
520 }
521 case DW_AT_specification:
522 case DW_AT_abstract_origin: {
523 if (auto ReferencedDie = Die.getAttributeValueAsReferencedDie(Attr)) {
524 auto DieTag = Die.getTag();
525 auto RefTag = ReferencedDie.getTag();
526 if (DieTag == RefTag)
527 break;
528 if (DieTag == DW_TAG_inlined_subroutine && RefTag == DW_TAG_subprogram)
529 break;
530 if (DieTag == DW_TAG_variable && RefTag == DW_TAG_member)
531 break;
532 ReportError("DIE with tag " + TagString(DieTag) + " has " +
533 AttributeString(Attr) +
534 " that points to DIE with "
535 "incompatible tag " +
536 TagString(RefTag));
537 }
538 break;
539 }
540 case DW_AT_type: {
541 DWARFDie TypeDie = Die.getAttributeValueAsReferencedDie(DW_AT_type);
542 if (TypeDie && !isType(TypeDie.getTag())) {
543 ReportError("DIE has " + AttributeString(Attr) +
544 " with incompatible tag " + TagString(TypeDie.getTag()));
545 }
546 break;
547 }
548 default:
549 break;
550 }
551 return NumErrors;
552}
553
554unsigned DWARFVerifier::verifyDebugInfoForm(const DWARFDie &Die,
555 DWARFAttribute &AttrValue) {
556 const DWARFObject &DObj = DCtx.getDWARFObj();
557 auto DieCU = Die.getDwarfUnit();
558 unsigned NumErrors = 0;
559 const auto Form = AttrValue.Value.getForm();
560 switch (Form) {
561 case DW_FORM_ref1:
562 case DW_FORM_ref2:
563 case DW_FORM_ref4:
564 case DW_FORM_ref8:
565 case DW_FORM_ref_udata: {
566 // Verify all CU relative references are valid CU offsets.
567 Optional<uint64_t> RefVal = AttrValue.Value.getAsReference();
568 assert(RefVal)((RefVal) ? static_cast<void> (0) : __assert_fail ("RefVal"
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF/DWARFVerifier.cpp"
, 568, __PRETTY_FUNCTION__))
;
569 if (RefVal) {
570 auto CUSize = DieCU->getNextUnitOffset() - DieCU->getOffset();
571 auto CUOffset = AttrValue.Value.getRawUValue();
572 if (CUOffset >= CUSize) {
573 ++NumErrors;
574 error() << FormEncodingString(Form) << " CU offset "
575 << format("0x%08" PRIx64"l" "x", CUOffset)
576 << " is invalid (must be less than CU size of "
577 << format("0x%08" PRIx32"x", CUSize) << "):\n";
578 Die.dump(OS, 0, DumpOpts);
579 dump(Die) << '\n';
580 } else {
581 // Valid reference, but we will verify it points to an actual
582 // DIE later.
583 ReferenceToDIEOffsets[*RefVal].insert(Die.getOffset());
584 }
585 }
586 break;
587 }
588 case DW_FORM_ref_addr: {
589 // Verify all absolute DIE references have valid offsets in the
590 // .debug_info section.
591 Optional<uint64_t> RefVal = AttrValue.Value.getAsReference();
592 assert(RefVal)((RefVal) ? static_cast<void> (0) : __assert_fail ("RefVal"
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF/DWARFVerifier.cpp"
, 592, __PRETTY_FUNCTION__))
;
593 if (RefVal) {
594 if (*RefVal >= DieCU->getInfoSection().Data.size()) {
595 ++NumErrors;
596 error() << "DW_FORM_ref_addr offset beyond .debug_info "
597 "bounds:\n";
598 dump(Die) << '\n';
599 } else {
600 // Valid reference, but we will verify it points to an actual
601 // DIE later.
602 ReferenceToDIEOffsets[*RefVal].insert(Die.getOffset());
603 }
604 }
605 break;
606 }
607 case DW_FORM_strp: {
608 auto SecOffset = AttrValue.Value.getAsSectionOffset();
609 assert(SecOffset)((SecOffset) ? static_cast<void> (0) : __assert_fail ("SecOffset"
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF/DWARFVerifier.cpp"
, 609, __PRETTY_FUNCTION__))
; // DW_FORM_strp is a section offset.
610 if (SecOffset && *SecOffset >= DObj.getStringSection().size()) {
611 ++NumErrors;
612 error() << "DW_FORM_strp offset beyond .debug_str bounds:\n";
613 dump(Die) << '\n';
614 }
615 break;
616 }
617 case DW_FORM_strx:
618 case DW_FORM_strx1:
619 case DW_FORM_strx2:
620 case DW_FORM_strx3:
621 case DW_FORM_strx4: {
622 auto Index = AttrValue.Value.getRawUValue();
623 auto DieCU = Die.getDwarfUnit();
624 // Check that we have a valid DWARF v5 string offsets table.
625 if (!DieCU->getStringOffsetsTableContribution()) {
626 ++NumErrors;
627 error() << FormEncodingString(Form)
628 << " used without a valid string offsets table:\n";
629 dump(Die) << '\n';
630 break;
631 }
632 // Check that the index is within the bounds of the section.
633 unsigned ItemSize = DieCU->getDwarfStringOffsetsByteSize();
634 // Use a 64-bit type to calculate the offset to guard against overflow.
635 uint64_t Offset =
636 (uint64_t)DieCU->getStringOffsetsBase() + Index * ItemSize;
637 if (DObj.getStringOffsetSection().Data.size() < Offset + ItemSize) {
638 ++NumErrors;
639 error() << FormEncodingString(Form) << " uses index "
640 << format("%" PRIu64"l" "u", Index) << ", which is too large:\n";
641 dump(Die) << '\n';
642 break;
643 }
644 // Check that the string offset is valid.
645 uint64_t StringOffset = *DieCU->getStringOffsetSectionItem(Index);
646 if (StringOffset >= DObj.getStringSection().size()) {
647 ++NumErrors;
648 error() << FormEncodingString(Form) << " uses index "
649 << format("%" PRIu64"l" "u", Index)
650 << ", but the referenced string"
651 " offset is beyond .debug_str bounds:\n";
652 dump(Die) << '\n';
653 }
654 break;
655 }
656 default:
657 break;
658 }
659 return NumErrors;
660}
661
662unsigned DWARFVerifier::verifyDebugInfoReferences() {
663 // Take all references and make sure they point to an actual DIE by
664 // getting the DIE by offset and emitting an error
665 OS << "Verifying .debug_info references...\n";
666 unsigned NumErrors = 0;
667 for (auto Pair : ReferenceToDIEOffsets) {
668 auto Die = DCtx.getDIEForOffset(Pair.first);
669 if (Die)
670 continue;
671 ++NumErrors;
672 error() << "invalid DIE reference " << format("0x%08" PRIx64"l" "x", Pair.first)
673 << ". Offset is in between DIEs:\n";
674 for (auto Offset : Pair.second)
675 dump(DCtx.getDIEForOffset(Offset)) << '\n';
676 OS << "\n";
677 }
678 return NumErrors;
679}
680
681void DWARFVerifier::verifyDebugLineStmtOffsets() {
682 std::map<uint64_t, DWARFDie> StmtListToDie;
683 for (const auto &CU : DCtx.compile_units()) {
684 auto Die = CU->getUnitDIE();
685 // Get the attribute value as a section offset. No need to produce an
686 // error here if the encoding isn't correct because we validate this in
687 // the .debug_info verifier.
688 auto StmtSectionOffset = toSectionOffset(Die.find(DW_AT_stmt_list));
689 if (!StmtSectionOffset)
690 continue;
691 const uint32_t LineTableOffset = *StmtSectionOffset;
692 auto LineTable = DCtx.getLineTableForUnit(CU.get());
693 if (LineTableOffset < DCtx.getDWARFObj().getLineSection().Data.size()) {
694 if (!LineTable) {
695 ++NumDebugLineErrors;
696 error() << ".debug_line[" << format("0x%08" PRIx32"x", LineTableOffset)
697 << "] was not able to be parsed for CU:\n";
698 dump(Die) << '\n';
699 continue;
700 }
701 } else {
702 // Make sure we don't get a valid line table back if the offset is wrong.
703 assert(LineTable == nullptr)((LineTable == nullptr) ? static_cast<void> (0) : __assert_fail
("LineTable == nullptr", "/build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF/DWARFVerifier.cpp"
, 703, __PRETTY_FUNCTION__))
;
704 // Skip this line table as it isn't valid. No need to create an error
705 // here because we validate this in the .debug_info verifier.
706 continue;
707 }
708 auto Iter = StmtListToDie.find(LineTableOffset);
709 if (Iter != StmtListToDie.end()) {
710 ++NumDebugLineErrors;
711 error() << "two compile unit DIEs, "
712 << format("0x%08" PRIx32"x", Iter->second.getOffset()) << " and "
713 << format("0x%08" PRIx32"x", Die.getOffset())
714 << ", have the same DW_AT_stmt_list section offset:\n";
715 dump(Iter->second);
716 dump(Die) << '\n';
717 // Already verified this line table before, no need to do it again.
718 continue;
719 }
720 StmtListToDie[LineTableOffset] = Die;
721 }
722}
723
724void DWARFVerifier::verifyDebugLineRows() {
725 for (const auto &CU : DCtx.compile_units()) {
726 auto Die = CU->getUnitDIE();
727 auto LineTable = DCtx.getLineTableForUnit(CU.get());
728 // If there is no line table we will have created an error in the
729 // .debug_info verifier or in verifyDebugLineStmtOffsets().
730 if (!LineTable)
731 continue;
732
733 // Verify prologue.
734 uint32_t MaxFileIndex = LineTable->Prologue.FileNames.size();
735 uint32_t MaxDirIndex = LineTable->Prologue.IncludeDirectories.size();
736 uint32_t FileIndex = 1;
737 StringMap<uint16_t> FullPathMap;
738 for (const auto &FileName : LineTable->Prologue.FileNames) {
739 // Verify directory index.
740 if (FileName.DirIdx > MaxDirIndex) {
741 ++NumDebugLineErrors;
742 error() << ".debug_line["
743 << format("0x%08" PRIx64"l" "x",
744 *toSectionOffset(Die.find(DW_AT_stmt_list)))
745 << "].prologue.file_names[" << FileIndex
746 << "].dir_idx contains an invalid index: " << FileName.DirIdx
747 << "\n";
748 }
749
750 // Check file paths for duplicates.
751 std::string FullPath;
752 const bool HasFullPath = LineTable->getFileNameByIndex(
753 FileIndex, CU->getCompilationDir(),
754 DILineInfoSpecifier::FileLineInfoKind::AbsoluteFilePath, FullPath);
755 assert(HasFullPath && "Invalid index?")((HasFullPath && "Invalid index?") ? static_cast<void
> (0) : __assert_fail ("HasFullPath && \"Invalid index?\""
, "/build/llvm-toolchain-snapshot-8~svn350071/lib/DebugInfo/DWARF/DWARFVerifier.cpp"
, 755, __PRETTY_FUNCTION__))
;
756 (void)HasFullPath;
757 auto It = FullPathMap.find(FullPath);
758 if (It == FullPathMap.end())
759 FullPathMap[FullPath] = FileIndex;
760 else if (It->second != FileIndex) {
761 warn() << ".debug_line["
762 << format("0x%08" PRIx64"l" "x",
763 *toSectionOffset(Die.find(DW_AT_stmt_list)))
764 << "].prologue.file_names[" << FileIndex
765 << "] is a duplicate of file_names[" << It->second << "]\n";
766 }
767
768 FileIndex++;
769 }
770
771 // Verify rows.
772 uint64_t PrevAddress = 0;
773 uint32_t RowIndex = 0;
774 for (const auto &Row : LineTable->Rows) {
775 // Verify row address.
776 if (Row.Address < PrevAddress) {
777 ++NumDebugLineErrors;
778 error() << ".debug_line["
779 << format("0x%08" PRIx64"l" "x",
780 *toSectionOffset(Die.find(DW_AT_stmt_list)))
781 << "] row[" << RowIndex
782 << "] decreases in address from previous row:\n";
783
784 DWARFDebugLine::Row::dumpTableHeader(OS);
785 if (RowIndex > 0)
786 LineTable->Rows[RowIndex - 1].dump(OS);
787 Row.dump(OS);
788 OS << '\n';
789 }
790
791 // Verify file index.
792 if (Row.File > MaxFileIndex) {
793 ++NumDebugLineErrors;
794 error() << ".debug_line["
795 << format("0x%08" PRIx64"l" "x",
796 *toSectionOffset(Die.find(DW_AT_stmt_list)))
797 << "][" << RowIndex << "] has invalid file index " << Row.File
798 << " (valid values are [1," << MaxFileIndex << "]):\n";
799 DWARFDebugLine::Row::dumpTableHeader(OS);
800 Row.dump(OS);
801 OS << '\n';
802 }
803 if (Row.EndSequence)
804 PrevAddress = 0;
805 else
806 PrevAddress = Row.Address;
807 ++RowIndex;
808 }
809 }
810}
811
812DWARFVerifier::DWARFVerifier(raw_ostream &S, DWARFContext &D,
813 DIDumpOptions DumpOpts)
814 : OS(S), DCtx(D), DumpOpts(std::move(DumpOpts)), IsObjectFile(false),
815 IsMachOObject(false) {
816 if (const auto *F = DCtx.getDWARFObj().getFile()) {
817 IsObjectFile = F->isRelocatableObject();
818 IsMachOObject = F->isMachO();
819 }
820}
821
822bool DWARFVerifier::handleDebugLine() {
823 NumDebugLineErrors = 0;
824 OS << "Verifying .debug_line...\n";
825 verifyDebugLineStmtOffsets();
826 verifyDebugLineRows();
827 return NumDebugLineErrors == 0;
828}
829
830unsigned DWARFVerifier::verifyAppleAccelTable(const DWARFSection *AccelSection,
831 DataExtractor *StrData,
832 const char *SectionName) {
833 unsigned NumErrors = 0;
834 DWARFDataExtractor AccelSectionData(DCtx.getDWARFObj(), *AccelSection,
835 DCtx.isLittleEndian(), 0);
836 AppleAcceleratorTable AccelTable(AccelSectionData, *StrData);
837
838 OS << "Verifying " << SectionName << "...\n";
839
840 // Verify that the fixed part of the header is not too short.
841 if (!AccelSectionData.isValidOffset(AccelTable.getSizeHdr())) {
842 error() << "Section is too small to fit a section header.\n";
843 return 1;
844 }
845
846 // Verify that the section is not too short.
847 if (Error E = AccelTable.extract()) {
848 error() << toString(std::move(E)) << '\n';
849 return 1;
850 }
851
852 // Verify that all buckets have a valid hash index or are empty.
853 uint32_t NumBuckets = AccelTable.getNumBuckets();
854 uint32_t NumHashes = AccelTable.getNumHashes();
855
856 uint32_t BucketsOffset =
857 AccelTable.getSizeHdr() + AccelTable.getHeaderDataLength();
858 uint32_t HashesBase = BucketsOffset + NumBuckets * 4;
859 uint32_t OffsetsBase = HashesBase + NumHashes * 4;
860 for (uint32_t BucketIdx = 0; BucketIdx < NumBuckets; ++BucketIdx) {
861 uint32_t HashIdx = AccelSectionData.getU32(&BucketsOffset);
862 if (HashIdx >= NumHashes && HashIdx != UINT32_MAX(4294967295U)) {
863 error() << format("Bucket[%d] has invalid hash index: %u.\n", BucketIdx,
864 HashIdx);
865 ++NumErrors;
866 }
867 }
868 uint32_t NumAtoms = AccelTable.getAtomsDesc().size();
869 if (NumAtoms == 0) {
870 error() << "No atoms: failed to read HashData.\n";
871 return 1;
872 }
873 if (!AccelTable.validateForms()) {
874 error() << "Unsupported form: failed to read HashData.\n";
875 return 1;
876 }
877
878 for (uint32_t HashIdx = 0; HashIdx < NumHashes; ++HashIdx) {
879 uint32_t HashOffset = HashesBase + 4 * HashIdx;
880 uint32_t DataOffset = OffsetsBase + 4 * HashIdx;
881 uint32_t Hash = AccelSectionData.getU32(&HashOffset);
882 uint32_t HashDataOffset = AccelSectionData.getU32(&DataOffset);
883 if (!AccelSectionData.isValidOffsetForDataOfSize(HashDataOffset,
884 sizeof(uint64_t))) {
885 error() << format("Hash[%d] has invalid HashData offset: 0x%08x.\n",
886 HashIdx, HashDataOffset);
887 ++NumErrors;
888 }
889
890 uint32_t StrpOffset;
891 uint32_t StringOffset;
892 uint32_t StringCount = 0;
893 unsigned Offset;
894 unsigned Tag;
895 while ((StrpOffset = AccelSectionData.getU32(&HashDataOffset)) != 0) {
896 const uint32_t NumHashDataObjects =
897 AccelSectionData.getU32(&HashDataOffset);
898 for (uint32_t HashDataIdx = 0; HashDataIdx < NumHashDataObjects;
899 ++HashDataIdx) {
900 std::tie(Offset, Tag) = AccelTable.readAtoms(HashDataOffset);
901 auto Die = DCtx.getDIEForOffset(Offset);
902 if (!Die) {
903 const uint32_t BucketIdx =
904 NumBuckets ? (Hash % NumBuckets) : UINT32_MAX(4294967295U);
905 StringOffset = StrpOffset;
906 const char *Name = StrData->getCStr(&StringOffset);
907 if (!Name)
908 Name = "<NULL>";
909
910 error() << format(
911 "%s Bucket[%d] Hash[%d] = 0x%08x "
912 "Str[%u] = 0x%08x "
913 "DIE[%d] = 0x%08x is not a valid DIE offset for \"%s\".\n",
914 SectionName, BucketIdx, HashIdx, Hash, StringCount, StrpOffset,
915 HashDataIdx, Offset, Name);
916
917 ++NumErrors;
918 continue;
919 }
920 if ((Tag != dwarf::DW_TAG_null) && (Die.getTag() != Tag)) {
921 error() << "Tag " << dwarf::TagString(Tag)
922 << " in accelerator table does not match Tag "
923 << dwarf::TagString(Die.getTag()) << " of DIE[" << HashDataIdx
924 << "].\n";
925 ++NumErrors;
926 }
927 }
928 ++StringCount;
929 }
930 }
931 return NumErrors;
932}
933
934unsigned
935DWARFVerifier::verifyDebugNamesCULists(const DWARFDebugNames &AccelTable) {
936 // A map from CU offset to the (first) Name Index offset which claims to index
937 // this CU.
938 DenseMap<uint32_t, uint32_t> CUMap;
939 const uint32_t NotIndexed = std::numeric_limits<uint32_t>::max();
940
941 CUMap.reserve(DCtx.getNumCompileUnits());
942 for (const auto &CU : DCtx.compile_units())
943 CUMap[CU->getOffset()] = NotIndexed;
944
945 unsigned NumErrors = 0;
946 for (const DWARFDebugNames::NameIndex &NI : AccelTable) {
947 if (NI.getCUCount() == 0) {
948 error() << formatv("Name Index @ {0:x} does not index any CU\n",
949 NI.getUnitOffset());
950 ++NumErrors;
951 continue;
952 }
953 for (uint32_t CU = 0, End = NI.getCUCount(); CU < End; ++CU) {
954 uint32_t Offset = NI.getCUOffset(CU);
955 auto Iter = CUMap.find(Offset);
956
957 if (Iter == CUMap.end()) {
958 error() << formatv(
959 "Name Index @ {0:x} references a non-existing CU @ {1:x}\n",
960 NI.getUnitOffset(), Offset);
961 ++NumErrors;
962 continue;
963 }
964
965 if (Iter->second != NotIndexed) {
966 error() << formatv("Name Index @ {0:x} references a CU @ {1:x}, but "
967 "this CU is already indexed by Name Index @ {2:x}\n",
968 NI.getUnitOffset(), Offset, Iter->second);
969 continue;
970 }
971 Iter->second = NI.getUnitOffset();
972 }
973 }
974
975 for (const auto &KV : CUMap) {
976 if (KV.second == NotIndexed)
977 warn() << formatv("CU @ {0:x} not covered by any Name Index\n", KV.first);
978 }
979
980 return NumErrors;
981}
982
983unsigned
984DWARFVerifier::verifyNameIndexBuckets(const DWARFDebugNames::NameIndex &NI,
985 const DataExtractor &StrData) {
986 struct BucketInfo {
987 uint32_t Bucket;
988 uint32_t Index;
989
990 constexpr BucketInfo(uint32_t Bucket, uint32_t Index)
991 : Bucket(Bucket), Index(Index) {}
992 bool operator<(const BucketInfo &RHS) const { return Index < RHS.Index; };
993 };
994
995 uint32_t NumErrors = 0;
996 if (NI.getBucketCount() == 0) {
997 warn() << formatv("Name Index @ {0:x} does not contain a hash table.\n",
998 NI.getUnitOffset());
999 return NumErrors;
1000 }
1001
1002 // Build up a list of (Bucket, Index) pairs. We use this later to verify that
1003 // each Name is reachable from the appropriate bucket.
1004 std::vector<BucketInfo> BucketStarts;
1005 BucketStarts.reserve(NI.getBucketCount() + 1);
1006 for (uint32_t Bucket = 0, End = NI.getBucketCount(); Bucket < End; ++Bucket) {
1007 uint32_t Index = NI.getBucketArrayEntry(Bucket);
1008 if (Index > NI.getNameCount()) {
1009 error() << formatv("Bucket {0} of Name Index @ {1:x} contains invalid "
1010 "value {2}. Valid range is [0, {3}].\n",
1011 Bucket, NI.getUnitOffset(), Index, NI.getNameCount());
1012 ++NumErrors;
1013 continue;
1014 }
1015 if (Index > 0)
1016 BucketStarts.emplace_back(Bucket, Index);
1017 }
1018
1019 // If there were any buckets with invalid values, skip further checks as they
1020 // will likely produce many errors which will only confuse the actual root
1021 // problem.
1022 if (NumErrors > 0)
1023 return NumErrors;
1024
1025 // Sort the list in the order of increasing "Index" entries.
1026 array_pod_sort(BucketStarts.begin(), BucketStarts.end());
1027
1028 // Insert a sentinel entry at the end, so we can check that the end of the
1029 // table is covered in the loop below.
1030 BucketStarts.emplace_back(NI.getBucketCount(), NI.getNameCount() + 1);
1031
1032 // Loop invariant: NextUncovered is the (1-based) index of the first Name
1033 // which is not reachable by any of the buckets we processed so far (and
1034 // hasn't been reported as uncovered).
1035 uint32_t NextUncovered = 1;
1036 for (const BucketInfo &B : BucketStarts) {
1037 // Under normal circumstances B.Index be equal to NextUncovered, but it can
1038 // be less if a bucket points to names which are already known to be in some
1039 // bucket we processed earlier. In that case, we won't trigger this error,
1040 // but report the mismatched hash value error instead. (We know the hash
1041 // will not match because we have already verified that the name's hash
1042 // puts it into the previous bucket.)
1043 if (B.Index > NextUncovered) {
1044 error() << formatv("Name Index @ {0:x}: Name table entries [{1}, {2}] "
1045 "are not covered by the hash table.\n",
1046 NI.getUnitOffset(), NextUncovered, B.Index - 1);
1047 ++NumErrors;
1048 }
1049 uint32_t Idx = B.Index;
1050
1051 // The rest of the checks apply only to non-sentinel entries.
1052 if (B.Bucket == NI.getBucketCount())
1053 break;
1054
1055 // This triggers if a non-empty bucket points to a name with a mismatched
1056 // hash. Clients are likely to interpret this as an empty bucket, because a
1057 // mismatched hash signals the end of a bucket, but if this is indeed an
1058 // empty bucket, the producer should have signalled this by marking the
1059 // bucket as empty.
1060 uint32_t FirstHash = NI.getHashArrayEntry(Idx);
1061 if (FirstHash % NI.getBucketCount() != B.Bucket) {
1062 error() << formatv(
1063 "Name Index @ {0:x}: Bucket {1} is not empty but points to a "
1064 "mismatched hash value {2:x} (belonging to bucket {3}).\n",
1065 NI.getUnitOffset(), B.Bucket, FirstHash,
1066 FirstHash % NI.getBucketCount());
1067 ++NumErrors;
1068 }
1069
1070 // This find the end of this bucket and also verifies that all the hashes in
1071 // this bucket are correct by comparing the stored hashes to the ones we
1072 // compute ourselves.
1073 while (Idx <= NI.getNameCount()) {
1074 uint32_t Hash = NI.getHashArrayEntry(Idx);
1075 if (Hash % NI.getBucketCount() != B.Bucket)
1076 break;
1077
1078 const char *Str = NI.getNameTableEntry(Idx).getString();
1079 if (caseFoldingDjbHash(Str) != Hash) {
1080 error() << formatv("Name Index @ {0:x}: String ({1}) at index {2} "
1081 "hashes to {3:x}, but "
1082 "the Name Index hash is {4:x}\n",
1083 NI.getUnitOffset(), Str, Idx,
1084 caseFoldingDjbHash(Str), Hash);
1085 ++NumErrors;
1086 }
1087
1088 ++Idx;
1089 }
1090 NextUncovered = std::max(NextUncovered, Idx);
1091 }
1092 return NumErrors;
1093}
1094
1095unsigned DWARFVerifier::verifyNameIndexAttribute(
1096 const DWARFDebugNames::NameIndex &NI, const DWARFDebugNames::Abbrev &Abbr,
1097 DWARFDebugNames::AttributeEncoding AttrEnc) {
1098 StringRef FormName = dwarf::FormEncodingString(AttrEnc.Form);
1099 if (FormName.empty()) {
1100 error() << formatv("NameIndex @ {0:x}: Abbreviation {1:x}: {2} uses an "
1101 "unknown form: {3}.\n",
1102 NI.getUnitOffset(), Abbr.Code, AttrEnc.Index,
1103 AttrEnc.Form);
1104 return 1;
1105 }
1106
1107 if (AttrEnc.Index == DW_IDX_type_hash) {
1108 if (AttrEnc.Form != dwarf::DW_FORM_data8) {
1109 error() << formatv(
1110 "NameIndex @ {0:x}: Abbreviation {1:x}: DW_IDX_type_hash "
1111 "uses an unexpected form {2} (should be {3}).\n",
1112 NI.getUnitOffset(), Abbr.Code, AttrEnc.Form, dwarf::DW_FORM_data8);
1113 return 1;
1114 }
1115 }
1116
1117 // A list of known index attributes and their expected form classes.
1118 // DW_IDX_type_hash is handled specially in the check above, as it has a
1119 // specific form (not just a form class) we should expect.
1120 struct FormClassTable {
1121 dwarf::Index Index;
1122 DWARFFormValue::FormClass Class;
1123 StringLiteral ClassName;
1124 };
1125 static constexpr FormClassTable Table[] = {
1126 {dwarf::DW_IDX_compile_unit, DWARFFormValue::FC_Constant, {"constant"}},
1127 {dwarf::DW_IDX_type_unit, DWARFFormValue::FC_Constant, {"constant"}},
1128 {dwarf::DW_IDX_die_offset, DWARFFormValue::FC_Reference, {"reference"}},
1129 {dwarf::DW_IDX_parent, DWARFFormValue::FC_Constant, {"constant"}},
1130 };
1131
1132 ArrayRef<FormClassTable> TableRef(Table);
1133 auto Iter = find_if(TableRef, [AttrEnc](const FormClassTable &T) {
1134 return T.Index == AttrEnc.Index;
1135 });
1136 if (Iter == TableRef.end()) {
1137 warn() << formatv("NameIndex @ {0:x}: Abbreviation {1:x} contains an "
1138 "unknown index attribute: {2}.\n",
1139 NI.getUnitOffset(), Abbr.Code, AttrEnc.Index);
1140 return 0;
1141 }
1142
1143 if (!DWARFFormValue(AttrEnc.Form).isFormClass(Iter->Class)) {
1144 error() << formatv("NameIndex @ {0:x}: Abbreviation {1:x}: {2} uses an "
1145 "unexpected form {3} (expected form class {4}).\n",
1146 NI.getUnitOffset(), Abbr.Code, AttrEnc.Index,
1147 AttrEnc.Form, Iter->ClassName);
1148 return 1;
1149 }
1150 return 0;
1151}
1152
1153unsigned
1154DWARFVerifier::verifyNameIndexAbbrevs(const DWARFDebugNames::NameIndex &NI) {
1155 if (NI.getLocalTUCount() + NI.getForeignTUCount() > 0) {
1156 warn() << formatv("Name Index @ {0:x}: Verifying indexes of type units is "
1157 "not currently supported.\n",
1158 NI.getUnitOffset());
1159 return 0;
1160 }
1161
1162 unsigned NumErrors = 0;
1163 for (const auto &Abbrev : NI.getAbbrevs()) {
1164 StringRef TagName = dwarf::TagString(Abbrev.Tag);
1165 if (TagName.empty()) {
1166 warn() << formatv("NameIndex @ {0:x}: Abbreviation {1:x} references an "
1167 "unknown tag: {2}.\n",
1168 NI.getUnitOffset(), Abbrev.Code, Abbrev.Tag);
1169 }
1170 SmallSet<unsigned, 5> Attributes;
1171 for (const auto &AttrEnc : Abbrev.Attributes) {
1172 if (!Attributes.insert(AttrEnc.Index).second) {
1173 error() << formatv("NameIndex @ {0:x}: Abbreviation {1:x} contains "
1174 "multiple {2} attributes.\n",
1175 NI.getUnitOffset(), Abbrev.Code, AttrEnc.Index);
1176 ++NumErrors;
1177 continue;
1178 }
1179 NumErrors += verifyNameIndexAttribute(NI, Abbrev, AttrEnc);
1180 }
1181
1182 if (NI.getCUCount() > 1 && !Attributes.count(dwarf::DW_IDX_compile_unit)) {
1183 error() << formatv("NameIndex @ {0:x}: Indexing multiple compile units "
1184 "and abbreviation {1:x} has no {2} attribute.\n",
1185 NI.getUnitOffset(), Abbrev.Code,
1186 dwarf::DW_IDX_compile_unit);
1187 ++NumErrors;
1188 }
1189 if (!Attributes.count(dwarf::DW_IDX_die_offset)) {
1190 error() << formatv(
1191 "NameIndex @ {0:x}: Abbreviation {1:x} has no {2} attribute.\n",
1192 NI.getUnitOffset(), Abbrev.Code, dwarf::DW_IDX_die_offset);
1193 ++NumErrors;
1194 }
1195 }
1196 return NumErrors;
1197}
1198
1199static SmallVector<StringRef, 2> getNames(const DWARFDie &DIE,
1200 bool IncludeLinkageName = true) {
1201 SmallVector<StringRef, 2> Result;
1202 if (const char *Str = DIE.getName(DINameKind::ShortName))
1203 Result.emplace_back(Str);
1204 else if (DIE.getTag() == dwarf::DW_TAG_namespace)
1205 Result.emplace_back("(anonymous namespace)");
1206
1207 if (IncludeLinkageName) {
1208 if (const char *Str = DIE.getName(DINameKind::LinkageName)) {
1209 if (Result.empty() || Result[0] != Str)
1210 Result.emplace_back(Str);
1211 }
1212 }
1213
1214 return Result;
1215}
1216
1217unsigned DWARFVerifier::verifyNameIndexEntries(
1218 const DWARFDebugNames::NameIndex &NI,
1219 const DWARFDebugNames::NameTableEntry &NTE) {
1220 // Verifying type unit indexes not supported.
1221 if (NI.getLocalTUCount() + NI.getForeignTUCount() > 0)
1222 return 0;
1223
1224 const char *CStr = NTE.getString();
1225 if (!CStr) {
1226 error() << formatv(
1227 "Name Index @ {0:x}: Unable to get string associated with name {1}.\n",
1228 NI.getUnitOffset(), NTE.getIndex());
1229 return 1;
1230 }
1231 StringRef Str(CStr);
1232
1233 unsigned NumErrors = 0;
1234 unsigned NumEntries = 0;
1235 uint32_t EntryID = NTE.getEntryOffset();
1236 uint32_t NextEntryID = EntryID;
1237 Expected<DWARFDebugNames::Entry> EntryOr = NI.getEntry(&NextEntryID);
1238 for (; EntryOr; ++NumEntries, EntryID = NextEntryID,
1239 EntryOr = NI.getEntry(&NextEntryID)) {
1240 uint32_t CUIndex = *EntryOr->getCUIndex();
1241 if (CUIndex > NI.getCUCount()) {
1242 error() << formatv("Name Index @ {0:x}: Entry @ {1:x} contains an "
1243 "invalid CU index ({2}).\n",
1244 NI.getUnitOffset(), EntryID, CUIndex);
1245 ++NumErrors;
1246 continue;
1247 }
1248 uint32_t CUOffset = NI.getCUOffset(CUIndex);
1249 uint64_t DIEOffset = CUOffset + *EntryOr->getDIEUnitOffset();
1250 DWARFDie DIE = DCtx.getDIEForOffset(DIEOffset);
1251 if (!DIE) {
1252 error() << formatv("Name Index @ {0:x}: Entry @ {1:x} references a "
1253 "non-existing DIE @ {2:x}.\n",
1254 NI.getUnitOffset(), EntryID, DIEOffset);
1255 ++NumErrors;
1256 continue;
1257 }
1258 if (DIE.getDwarfUnit()->getOffset() != CUOffset) {
1259 error() << formatv("Name Index @ {0:x}: Entry @ {1:x}: mismatched CU of "
1260 "DIE @ {2:x}: index - {3:x}; debug_info - {4:x}.\n",
1261 NI.getUnitOffset(), EntryID, DIEOffset, CUOffset,
1262 DIE.getDwarfUnit()->getOffset());
1263 ++NumErrors;
1264 }
1265 if (DIE.getTag() != EntryOr->tag()) {
1266 error() << formatv("Name Index @ {0:x}: Entry @ {1:x}: mismatched Tag of "
1267 "DIE @ {2:x}: index - {3}; debug_info - {4}.\n",
1268 NI.getUnitOffset(), EntryID, DIEOffset, EntryOr->tag(),
1269 DIE.getTag());
1270 ++NumErrors;
1271 }
1272
1273 auto EntryNames = getNames(DIE);
1274 if (!is_contained(EntryNames, Str)) {
1275 error() << formatv("Name Index @ {0:x}: Entry @ {1:x}: mismatched Name "
1276 "of DIE @ {2:x}: index - {3}; debug_info - {4}.\n",
1277 NI.getUnitOffset(), EntryID, DIEOffset, Str,
1278 make_range(EntryNames.begin(), EntryNames.end()));
1279 ++NumErrors;
1280 }
1281 }
1282 handleAllErrors(EntryOr.takeError(),
1283 [&](const DWARFDebugNames::SentinelError &) {
1284 if (NumEntries > 0)
1285 return;
1286 error() << formatv("Name Index @ {0:x}: Name {1} ({2}) is "
1287 "not associated with any entries.\n",
1288 NI.getUnitOffset(), NTE.getIndex(), Str);
1289 ++NumErrors;
1290 },
1291 [&](const ErrorInfoBase &Info) {
1292 error()
1293 << formatv("Name Index @ {0:x}: Name {1} ({2}): {3}\n",
1294 NI.getUnitOffset(), NTE.getIndex(), Str,
1295 Info.message());
1296 ++NumErrors;
1297 });
1298 return NumErrors;
1299}
1300
1301static bool isVariableIndexable(const DWARFDie &Die, DWARFContext &DCtx) {
1302 Optional<DWARFFormValue> Location = Die.findRecursively(DW_AT_location);
1303 if (!Location)
1304 return false;
1305
1306 auto ContainsInterestingOperators = [&](StringRef D) {
1307 DWARFUnit *U = Die.getDwarfUnit();
1308 DataExtractor Data(D, DCtx.isLittleEndian(), U->getAddressByteSize());
1309 DWARFExpression Expression(Data, U->getVersion(), U->getAddressByteSize());
1310 return any_of(Expression, [](DWARFExpression::Operation &Op) {
1311 return !Op.isError() && (Op.getCode() == DW_OP_addr ||
1312 Op.getCode() == DW_OP_form_tls_address ||
1313 Op.getCode() == DW_OP_GNU_push_tls_address);
1314 });
1315 };
1316
1317 if (Optional<ArrayRef<uint8_t>> Expr = Location->getAsBlock()) {
1318 // Inlined location.
1319 if (ContainsInterestingOperators(toStringRef(*Expr)))
1320 return true;
1321 } else if (Optional<uint64_t> Offset = Location->getAsSectionOffset()) {
1322 // Location list.
1323 if (const DWARFDebugLoc *DebugLoc = DCtx.getDebugLoc()) {
1324 if (const DWARFDebugLoc::LocationList *LocList =
1325 DebugLoc->getLocationListAtOffset(*Offset)) {
1326 if (any_of(LocList->Entries, [&](const DWARFDebugLoc::Entry &E) {
1327 return ContainsInterestingOperators({E.Loc.data(), E.Loc.size()});
1328 }))
1329 return true;
1330 }
1331 }
1332 }
1333 return false;
1334}
1335
1336unsigned DWARFVerifier::verifyNameIndexCompleteness(
1337 const DWARFDie &Die, const DWARFDebugNames::NameIndex &NI) {
1338
1339 // First check, if the Die should be indexed. The code follows the DWARF v5
1340 // wording as closely as possible.
1341
1342 // "All non-defining declarations (that is, debugging information entries
1343 // with a DW_AT_declaration attribute) are excluded."
1344 if (Die.find(DW_AT_declaration))
1345 return 0;
1346
1347 // "DW_TAG_namespace debugging information entries without a DW_AT_name
1348 // attribute are included with the name “(anonymous namespace)”.
1349 // All other debugging information entries without a DW_AT_name attribute
1350 // are excluded."
1351 // "If a subprogram or inlined subroutine is included, and has a
1352 // DW_AT_linkage_name attribute, there will be an additional index entry for
1353 // the linkage name."
1354 auto IncludeLinkageName = Die.getTag() == DW_TAG_subprogram ||
1355 Die.getTag() == DW_TAG_inlined_subroutine;
1356 auto EntryNames = getNames(Die, IncludeLinkageName);
1357 if (EntryNames.empty())
1358 return 0;
1359
1360 // We deviate from the specification here, which says:
1361 // "The name index must contain an entry for each debugging information entry
1362 // that defines a named subprogram, label, variable, type, or namespace,
1363 // subject to ..."
1364 // Instead whitelisting all TAGs representing a "type" or a "subprogram", to
1365 // make sure we catch any missing items, we instead blacklist all TAGs that we
1366 // know shouldn't be indexed.
1367 switch (Die.getTag()) {
1368 // Compile units and modules have names but shouldn't be indexed.
1369 case DW_TAG_compile_unit:
1370 case DW_TAG_module:
1371 return 0;
1372
1373 // Function and template parameters are not globally visible, so we shouldn't
1374 // index them.
1375 case DW_TAG_formal_parameter:
1376 case DW_TAG_template_value_parameter:
1377 case DW_TAG_template_type_parameter:
1378 case DW_TAG_GNU_template_parameter_pack:
1379 case DW_TAG_GNU_template_template_param:
1380 return 0;
1381
1382 // Object members aren't globally visible.
1383 case DW_TAG_member:
1384 return 0;
1385
1386 // According to a strict reading of the specification, enumerators should not
1387 // be indexed (and LLVM currently does not do that). However, this causes
1388 // problems for the debuggers, so we may need to reconsider this.
1389 case DW_TAG_enumerator:
1390 return 0;
1391
1392 // Imported declarations should not be indexed according to the specification
1393 // and LLVM currently does not do that.
1394 case DW_TAG_imported_declaration:
1395 return 0;
1396
1397 // "DW_TAG_subprogram, DW_TAG_inlined_subroutine, and DW_TAG_label debugging
1398 // information entries without an address attribute (DW_AT_low_pc,
1399 // DW_AT_high_pc, DW_AT_ranges, or DW_AT_entry_pc) are excluded."
1400 case DW_TAG_subprogram:
1401 case DW_TAG_inlined_subroutine:
1402 case DW_TAG_label:
1403 if (Die.findRecursively(
1404 {DW_AT_low_pc, DW_AT_high_pc, DW_AT_ranges, DW_AT_entry_pc}))
1405 break;
1406 return 0;
1407
1408 // "DW_TAG_variable debugging information entries with a DW_AT_location
1409 // attribute that includes a DW_OP_addr or DW_OP_form_tls_address operator are
1410 // included; otherwise, they are excluded."
1411 //
1412 // LLVM extension: We also add DW_OP_GNU_push_tls_address to this list.
1413 case DW_TAG_variable:
1414 if (isVariableIndexable(Die, DCtx))
1415 break;
1416 return 0;
1417
1418 default:
1419 break;
1420 }
1421
1422 // Now we know that our Die should be present in the Index. Let's check if
1423 // that's the case.
1424 unsigned NumErrors = 0;
1425 uint64_t DieUnitOffset = Die.getOffset() - Die.getDwarfUnit()->getOffset();
1426 for (StringRef Name : EntryNames) {
1427 if (none_of(NI.equal_range(Name), [&](const DWARFDebugNames::Entry &E) {
1428 return E.getDIEUnitOffset() == DieUnitOffset;
1429 })) {
1430 error() << formatv("Name Index @ {0:x}: Entry for DIE @ {1:x} ({2}) with "
1431 "name {3} missing.\n",
1432 NI.getUnitOffset(), Die.getOffset(), Die.getTag(),
1433 Name);
1434 ++NumErrors;
1435 }
1436 }
1437 return NumErrors;
1438}
1439
1440unsigned DWARFVerifier::verifyDebugNames(const DWARFSection &AccelSection,
1441 const DataExtractor &StrData) {
1442 unsigned NumErrors = 0;
1443 DWARFDataExtractor AccelSectionData(DCtx.getDWARFObj(), AccelSection,
1444 DCtx.isLittleEndian(), 0);
1445 DWARFDebugNames AccelTable(AccelSectionData, StrData);
1446
1447 OS << "Verifying .debug_names...\n";
1448
1449 // This verifies that we can read individual name indices and their
1450 // abbreviation tables.
1451 if (Error E = AccelTable.extract()) {
1452 error() << toString(std::move(E)) << '\n';
1453 return 1;
1454 }
1455
1456 NumErrors += verifyDebugNamesCULists(AccelTable);
1457 for (const auto &NI : AccelTable)
1458 NumErrors += verifyNameIndexBuckets(NI, StrData);
1459 for (const auto &NI : AccelTable)
1460 NumErrors += verifyNameIndexAbbrevs(NI);
1461
1462 // Don't attempt Entry validation if any of the previous checks found errors
1463 if (NumErrors > 0)
1464 return NumErrors;
1465 for (const auto &NI : AccelTable)
1466 for (DWARFDebugNames::NameTableEntry NTE : NI)
1467 NumErrors += verifyNameIndexEntries(NI, NTE);
1468
1469 if (NumErrors > 0)
1470 return NumErrors;
1471
1472 for (const std::unique_ptr<DWARFUnit> &U : DCtx.compile_units()) {
1473 if (const DWARFDebugNames::NameIndex *NI =
1474 AccelTable.getCUNameIndex(U->getOffset())) {
1475 auto *CU = cast<DWARFCompileUnit>(U.get());
1476 for (const DWARFDebugInfoEntry &Die : CU->dies())
1477 NumErrors += verifyNameIndexCompleteness(DWARFDie(CU, &Die), *NI);
1478 }
1479 }
1480 return NumErrors;
1481}
1482
1483bool DWARFVerifier::handleAccelTables() {
1484 const DWARFObject &D = DCtx.getDWARFObj();
1485 DataExtractor StrData(D.getStringSection(), DCtx.isLittleEndian(), 0);
1486 unsigned NumErrors = 0;
1487 if (!D.getAppleNamesSection().Data.empty())
1488 NumErrors += verifyAppleAccelTable(&D.getAppleNamesSection(), &StrData,
1489 ".apple_names");
1490 if (!D.getAppleTypesSection().Data.empty())
1491 NumErrors += verifyAppleAccelTable(&D.getAppleTypesSection(), &StrData,
1492 ".apple_types");
1493 if (!D.getAppleNamespacesSection().Data.empty())
1494 NumErrors += verifyAppleAccelTable(&D.getAppleNamespacesSection(), &StrData,
1495 ".apple_namespaces");
1496 if (!D.getAppleObjCSection().Data.empty())
1497 NumErrors += verifyAppleAccelTable(&D.getAppleObjCSection(), &StrData,
1498 ".apple_objc");
1499
1500 if (!D.getDebugNamesSection().Data.empty())
1501 NumErrors += verifyDebugNames(D.getDebugNamesSection(), StrData);
1502 return NumErrors == 0;
1503}
1504
1505raw_ostream &DWARFVerifier::error() const { return WithColor::error(OS); }
1506
1507raw_ostream &DWARFVerifier::warn() const { return WithColor::warning(OS); }
1508
1509raw_ostream &DWARFVerifier::note() const { return WithColor::note(OS); }
1510
1511raw_ostream &DWARFVerifier::dump(const DWARFDie &Die, unsigned indent) const {
1512 Die.dump(OS, indent, DumpOpts);
1513 return OS;
1514}

/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h

1//===- llvm/Support/Error.h - Recoverable error handling --------*- C++ -*-===//
2//
3// The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file defines an API used to report recoverable errors.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_SUPPORT_ERROR_H
15#define LLVM_SUPPORT_ERROR_H
16
17#include "llvm-c/Error.h"
18#include "llvm/ADT/STLExtras.h"
19#include "llvm/ADT/SmallVector.h"
20#include "llvm/ADT/StringExtras.h"
21#include "llvm/ADT/Twine.h"
22#include "llvm/Config/abi-breaking.h"
23#include "llvm/Support/AlignOf.h"
24#include "llvm/Support/Compiler.h"
25#include "llvm/Support/Debug.h"
26#include "llvm/Support/ErrorHandling.h"
27#include "llvm/Support/ErrorOr.h"
28#include "llvm/Support/Format.h"
29#include "llvm/Support/raw_ostream.h"
30#include <algorithm>
31#include <cassert>
32#include <cstdint>
33#include <cstdlib>
34#include <functional>
35#include <memory>
36#include <new>
37#include <string>
38#include <system_error>
39#include <type_traits>
40#include <utility>
41#include <vector>
42
43namespace llvm {
44
45class ErrorSuccess;
46
47/// Base class for error info classes. Do not extend this directly: Extend
48/// the ErrorInfo template subclass instead.
49class ErrorInfoBase {
50public:
51 virtual ~ErrorInfoBase() = default;
52
53 /// Print an error message to an output stream.
54 virtual void log(raw_ostream &OS) const = 0;
55
56 /// Return the error message as a string.
57 virtual std::string message() const {
58 std::string Msg;
59 raw_string_ostream OS(Msg);
60 log(OS);
61 return OS.str();
62 }
63
64 /// Convert this error to a std::error_code.
65 ///
66 /// This is a temporary crutch to enable interaction with code still
67 /// using std::error_code. It will be removed in the future.
68 virtual std::error_code convertToErrorCode() const = 0;
69
70 // Returns the class ID for this type.
71 static const void *classID() { return &ID; }
72
73 // Returns the class ID for the dynamic type of this ErrorInfoBase instance.
74 virtual const void *dynamicClassID() const = 0;
75
76 // Check whether this instance is a subclass of the class identified by
77 // ClassID.
78 virtual bool isA(const void *const ClassID) const {
79 return ClassID == classID();
80 }
81
82 // Check whether this instance is a subclass of ErrorInfoT.
83 template <typename ErrorInfoT> bool isA() const {
84 return isA(ErrorInfoT::classID());
85 }
86
87private:
88 virtual void anchor();
89
90 static char ID;
91};
92
93/// Lightweight error class with error context and mandatory checking.
94///
95/// Instances of this class wrap a ErrorInfoBase pointer. Failure states
96/// are represented by setting the pointer to a ErrorInfoBase subclass
97/// instance containing information describing the failure. Success is
98/// represented by a null pointer value.
99///
100/// Instances of Error also contains a 'Checked' flag, which must be set
101/// before the destructor is called, otherwise the destructor will trigger a
102/// runtime error. This enforces at runtime the requirement that all Error
103/// instances be checked or returned to the caller.
104///
105/// There are two ways to set the checked flag, depending on what state the
106/// Error instance is in. For Error instances indicating success, it
107/// is sufficient to invoke the boolean conversion operator. E.g.:
108///
109/// @code{.cpp}
110/// Error foo(<...>);
111///
112/// if (auto E = foo(<...>))
113/// return E; // <- Return E if it is in the error state.
114/// // We have verified that E was in the success state. It can now be safely
115/// // destroyed.
116/// @endcode
117///
118/// A success value *can not* be dropped. For example, just calling 'foo(<...>)'
119/// without testing the return value will raise a runtime error, even if foo
120/// returns success.
121///
122/// For Error instances representing failure, you must use either the
123/// handleErrors or handleAllErrors function with a typed handler. E.g.:
124///
125/// @code{.cpp}
126/// class MyErrorInfo : public ErrorInfo<MyErrorInfo> {
127/// // Custom error info.
128/// };
129///
130/// Error foo(<...>) { return make_error<MyErrorInfo>(...); }
131///
132/// auto E = foo(<...>); // <- foo returns failure with MyErrorInfo.
133/// auto NewE =
134/// handleErrors(E,
135/// [](const MyErrorInfo &M) {
136/// // Deal with the error.
137/// },
138/// [](std::unique_ptr<OtherError> M) -> Error {
139/// if (canHandle(*M)) {
140/// // handle error.
141/// return Error::success();
142/// }
143/// // Couldn't handle this error instance. Pass it up the stack.
144/// return Error(std::move(M));
145/// );
146/// // Note - we must check or return NewE in case any of the handlers
147/// // returned a new error.
148/// @endcode
149///
150/// The handleAllErrors function is identical to handleErrors, except
151/// that it has a void return type, and requires all errors to be handled and
152/// no new errors be returned. It prevents errors (assuming they can all be
153/// handled) from having to be bubbled all the way to the top-level.
154///
155/// *All* Error instances must be checked before destruction, even if
156/// they're moved-assigned or constructed from Success values that have already
157/// been checked. This enforces checking through all levels of the call stack.
158class LLVM_NODISCARD[[clang::warn_unused_result]] Error {
159 // Both ErrorList and FileError need to be able to yank ErrorInfoBase
160 // pointers out of this class to add to the error list.
161 friend class ErrorList;
162 friend class FileError;
163
164 // handleErrors needs to be able to set the Checked flag.
165 template <typename... HandlerTs>
166 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
167
168 // Expected<T> needs to be able to steal the payload when constructed from an
169 // error.
170 template <typename T> friend class Expected;
171
172 // wrap needs to be able to steal the payload.
173 friend LLVMErrorRef wrap(Error);
174
175protected:
176 /// Create a success value. Prefer using 'Error::success()' for readability
177 Error() {
178 setPtr(nullptr);
179 setChecked(false);
180 }
181
182public:
183 /// Create a success value.
184 static ErrorSuccess success();
185
186 // Errors are not copy-constructable.
187 Error(const Error &Other) = delete;
188
189 /// Move-construct an error value. The newly constructed error is considered
190 /// unchecked, even if the source error had been checked. The original error
191 /// becomes a checked Success value, regardless of its original state.
192 Error(Error &&Other) {
193 setChecked(true);
194 *this = std::move(Other);
195 }
196
197 /// Create an error value. Prefer using the 'make_error' function, but
198 /// this constructor can be useful when "re-throwing" errors from handlers.
199 Error(std::unique_ptr<ErrorInfoBase> Payload) {
200 setPtr(Payload.release());
201 setChecked(false);
31
Potential leak of memory pointed to by 'Payload._M_t._M_head_impl'
202 }
203
204 // Errors are not copy-assignable.
205 Error &operator=(const Error &Other) = delete;
206
207 /// Move-assign an error value. The current error must represent success, you
208 /// you cannot overwrite an unhandled error. The current error is then
209 /// considered unchecked. The source error becomes a checked success value,
210 /// regardless of its original state.
211 Error &operator=(Error &&Other) {
212 // Don't allow overwriting of unchecked values.
213 assertIsChecked();
214 setPtr(Other.getPtr());
215
216 // This Error is unchecked, even if the source error was checked.
217 setChecked(false);
218
219 // Null out Other's payload and set its checked bit.
220 Other.setPtr(nullptr);
221 Other.setChecked(true);
222
223 return *this;
224 }
225
226 /// Destroy a Error. Fails with a call to abort() if the error is
227 /// unchecked.
228 ~Error() {
229 assertIsChecked();
230 delete getPtr();
231 }
232
233 /// Bool conversion. Returns true if this Error is in a failure state,
234 /// and false if it is in an accept state. If the error is in a Success state
235 /// it will be considered checked.
236 explicit operator bool() {
237 setChecked(getPtr() == nullptr);
238 return getPtr() != nullptr;
239 }
240
241 /// Check whether one error is a subclass of another.
242 template <typename ErrT> bool isA() const {
243 return getPtr() && getPtr()->isA(ErrT::classID());
244 }
245
246 /// Returns the dynamic class id of this error, or null if this is a success
247 /// value.
248 const void* dynamicClassID() const {
249 if (!getPtr())
250 return nullptr;
251 return getPtr()->dynamicClassID();
252 }
253
254private:
255#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
256 // assertIsChecked() happens very frequently, but under normal circumstances
257 // is supposed to be a no-op. So we want it to be inlined, but having a bunch
258 // of debug prints can cause the function to be too large for inlining. So
259 // it's important that we define this function out of line so that it can't be
260 // inlined.
261 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
262 void fatalUncheckedError() const;
263#endif
264
265 void assertIsChecked() {
266#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
267 if (LLVM_UNLIKELY(!getChecked() || getPtr())__builtin_expect((bool)(!getChecked() || getPtr()), false))
268 fatalUncheckedError();
269#endif
270 }
271
272 ErrorInfoBase *getPtr() const {
273 return reinterpret_cast<ErrorInfoBase*>(
274 reinterpret_cast<uintptr_t>(Payload) &
275 ~static_cast<uintptr_t>(0x1));
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 Payload = reinterpret_cast<ErrorInfoBase*>(
299 (reinterpret_cast<uintptr_t>(Payload) &
300 ~static_cast<uintptr_t>(0x1)) |
301 (V ? 0 : 1));
302 }
303
304 std::unique_ptr<ErrorInfoBase> takePayload() {
305 std::unique_ptr<ErrorInfoBase> Tmp(getPtr());
306 setPtr(nullptr);
307 setChecked(true);
308 return Tmp;
309 }
310
311 friend raw_ostream &operator<<(raw_ostream &OS, const Error &E) {
312 if (auto P = E.getPtr())
313 P->log(OS);
314 else
315 OS << "success";
316 return OS;
317 }
318
319 ErrorInfoBase *Payload = nullptr;
320};
321
322/// Subclass of Error for the sole purpose of identifying the success path in
323/// the type system. This allows to catch invalid conversion to Expected<T> at
324/// compile time.
325class ErrorSuccess final : public Error {};
326
327inline ErrorSuccess Error::success() { return ErrorSuccess(); }
328
329/// Make a Error instance representing failure using the given error info
330/// type.
331template <typename ErrT, typename... ArgTs> Error make_error(ArgTs &&... Args) {
332 return Error(llvm::make_unique<ErrT>(std::forward<ArgTs>(Args)...));
333}
334
335/// Base class for user error types. Users should declare their error types
336/// like:
337///
338/// class MyError : public ErrorInfo<MyError> {
339/// ....
340/// };
341///
342/// This class provides an implementation of the ErrorInfoBase::kind
343/// method, which is used by the Error RTTI system.
344template <typename ThisErrT, typename ParentErrT = ErrorInfoBase>
345class ErrorInfo : public ParentErrT {
346public:
347 using ParentErrT::ParentErrT; // inherit constructors
348
349 static const void *classID() { return &ThisErrT::ID; }
350
351 const void *dynamicClassID() const override { return &ThisErrT::ID; }
352
353 bool isA(const void *const ClassID) const override {
354 return ClassID == classID() || ParentErrT::isA(ClassID);
355 }
356};
357
358/// Special ErrorInfo subclass representing a list of ErrorInfos.
359/// Instances of this class are constructed by joinError.
360class ErrorList final : public ErrorInfo<ErrorList> {
361 // handleErrors needs to be able to iterate the payload list of an
362 // ErrorList.
363 template <typename... HandlerTs>
364 friend Error handleErrors(Error E, HandlerTs &&... Handlers);
365
366 // joinErrors is implemented in terms of join.
367 friend Error joinErrors(Error, Error);
368
369public:
370 void log(raw_ostream &OS) const override {
371 OS << "Multiple errors:\n";
372 for (auto &ErrPayload : Payloads) {
373 ErrPayload->log(OS);
374 OS << "\n";
375 }
376 }
377
378 std::error_code convertToErrorCode() const override;
379
380 // Used by ErrorInfo::classID.
381 static char ID;
382
383private:
384 ErrorList(std::unique_ptr<ErrorInfoBase> Payload1,
385 std::unique_ptr<ErrorInfoBase> Payload2) {
386 assert(!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() &&((!Payload1->isA<ErrorList>() && !Payload2->
isA<ErrorList>() && "ErrorList constructor payloads should be singleton errors"
) ? static_cast<void> (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 387, __PRETTY_FUNCTION__))
387 "ErrorList constructor payloads should be singleton errors")((!Payload1->isA<ErrorList>() && !Payload2->
isA<ErrorList>() && "ErrorList constructor payloads should be singleton errors"
) ? static_cast<void> (0) : __assert_fail ("!Payload1->isA<ErrorList>() && !Payload2->isA<ErrorList>() && \"ErrorList constructor payloads should be singleton errors\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 387, __PRETTY_FUNCTION__))
;
388 Payloads.push_back(std::move(Payload1));
389 Payloads.push_back(std::move(Payload2));
390 }
391
392 static Error join(Error E1, Error E2) {
393 if (!E1)
23
Taking false branch
394 return E2;
395 if (!E2)
24
Taking false branch
396 return E1;
397 if (E1.isA<ErrorList>()) {
25
Assuming the condition is false
26
Taking false branch
398 auto &E1List = static_cast<ErrorList &>(*E1.getPtr());
399 if (E2.isA<ErrorList>()) {
400 auto E2Payload = E2.takePayload();
401 auto &E2List = static_cast<ErrorList &>(*E2Payload);
402 for (auto &Payload : E2List.Payloads)
403 E1List.Payloads.push_back(std::move(Payload));
404 } else
405 E1List.Payloads.push_back(E2.takePayload());
406
407 return E1;
408 }
409 if (E2.isA<ErrorList>()) {
27
Assuming the condition is false
28
Taking false branch
410 auto &E2List = static_cast<ErrorList &>(*E2.getPtr());
411 E2List.Payloads.insert(E2List.Payloads.begin(), E1.takePayload());
412 return E2;
413 }
414 return Error(std::unique_ptr<ErrorList>(
30
Calling constructor for 'Error'
415 new ErrorList(E1.takePayload(), E2.takePayload())));
29
Memory is allocated
416 }
417
418 std::vector<std::unique_ptr<ErrorInfoBase>> Payloads;
419};
420
421/// Concatenate errors. The resulting Error is unchecked, and contains the
422/// ErrorInfo(s), if any, contained in E1, followed by the
423/// ErrorInfo(s), if any, contained in E2.
424inline Error joinErrors(Error E1, Error E2) {
425 return ErrorList::join(std::move(E1), std::move(E2));
426}
427
428/// Tagged union holding either a T or a Error.
429///
430/// This class parallels ErrorOr, but replaces error_code with Error. Since
431/// Error cannot be copied, this class replaces getError() with
432/// takeError(). It also adds an bool errorIsA<ErrT>() method for testing the
433/// error class type.
434template <class T> class LLVM_NODISCARD[[clang::warn_unused_result]] Expected {
435 template <class T1> friend class ExpectedAsOutParameter;
436 template <class OtherT> friend class Expected;
437
438 static const bool isRef = std::is_reference<T>::value;
439
440 using wrap = std::reference_wrapper<typename std::remove_reference<T>::type>;
441
442 using error_type = std::unique_ptr<ErrorInfoBase>;
443
444public:
445 using storage_type = typename std::conditional<isRef, wrap, T>::type;
446 using value_type = T;
447
448private:
449 using reference = typename std::remove_reference<T>::type &;
450 using const_reference = const typename std::remove_reference<T>::type &;
451 using pointer = typename std::remove_reference<T>::type *;
452 using const_pointer = const typename std::remove_reference<T>::type *;
453
454public:
455 /// Create an Expected<T> error value from the given Error.
456 Expected(Error Err)
457 : HasError(true)
458#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
459 // Expected is unchecked upon construction in Debug builds.
460 , Unchecked(true)
461#endif
462 {
463 assert(Err && "Cannot create Expected<T> from Error success value.")((Err && "Cannot create Expected<T> from Error success value."
) ? static_cast<void> (0) : __assert_fail ("Err && \"Cannot create Expected<T> from Error success value.\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 463, __PRETTY_FUNCTION__))
;
464 new (getErrorStorage()) error_type(Err.takePayload());
465 }
466
467 /// Forbid to convert from Error::success() implicitly, this avoids having
468 /// Expected<T> foo() { return Error::success(); } which compiles otherwise
469 /// but triggers the assertion above.
470 Expected(ErrorSuccess) = delete;
471
472 /// Create an Expected<T> success value from the given OtherT value, which
473 /// must be convertible to T.
474 template <typename OtherT>
475 Expected(OtherT &&Val,
476 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
477 * = nullptr)
478 : HasError(false)
479#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
480 // Expected is unchecked upon construction in Debug builds.
481 , Unchecked(true)
482#endif
483 {
484 new (getStorage()) storage_type(std::forward<OtherT>(Val));
485 }
486
487 /// Move construct an Expected<T> value.
488 Expected(Expected &&Other) { moveConstruct(std::move(Other)); }
489
490 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
491 /// must be convertible to T.
492 template <class OtherT>
493 Expected(Expected<OtherT> &&Other,
494 typename std::enable_if<std::is_convertible<OtherT, T>::value>::type
495 * = nullptr) {
496 moveConstruct(std::move(Other));
497 }
498
499 /// Move construct an Expected<T> value from an Expected<OtherT>, where OtherT
500 /// isn't convertible to T.
501 template <class OtherT>
502 explicit Expected(
503 Expected<OtherT> &&Other,
504 typename std::enable_if<!std::is_convertible<OtherT, T>::value>::type * =
505 nullptr) {
506 moveConstruct(std::move(Other));
507 }
508
509 /// Move-assign from another Expected<T>.
510 Expected &operator=(Expected &&Other) {
511 moveAssign(std::move(Other));
512 return *this;
513 }
514
515 /// Destroy an Expected<T>.
516 ~Expected() {
517 assertIsChecked();
518 if (!HasError)
519 getStorage()->~storage_type();
520 else
521 getErrorStorage()->~error_type();
522 }
523
524 /// Return false if there is an error.
525 explicit operator bool() {
526#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
527 Unchecked = HasError;
528#endif
529 return !HasError;
530 }
531
532 /// Returns a reference to the stored T value.
533 reference get() {
534 assertIsChecked();
535 return *getStorage();
536 }
537
538 /// Returns a const reference to the stored T value.
539 const_reference get() const {
540 assertIsChecked();
541 return const_cast<Expected<T> *>(this)->get();
542 }
543
544 /// Check that this Expected<T> is an error of type ErrT.
545 template <typename ErrT> bool errorIsA() const {
546 return HasError && (*getErrorStorage())->template isA<ErrT>();
547 }
548
549 /// Take ownership of the stored error.
550 /// After calling this the Expected<T> is in an indeterminate state that can
551 /// only be safely destructed. No further calls (beside the destructor) should
552 /// be made on the Expected<T> vaule.
553 Error takeError() {
554#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
555 Unchecked = false;
556#endif
557 return HasError ? Error(std::move(*getErrorStorage())) : Error::success();
558 }
559
560 /// Returns a pointer to the stored T value.
561 pointer operator->() {
562 assertIsChecked();
563 return toPointer(getStorage());
564 }
565
566 /// Returns a const pointer to the stored T value.
567 const_pointer operator->() const {
568 assertIsChecked();
569 return toPointer(getStorage());
570 }
571
572 /// Returns a reference to the stored T value.
573 reference operator*() {
574 assertIsChecked();
575 return *getStorage();
576 }
577
578 /// Returns a const reference to the stored T value.
579 const_reference operator*() const {
580 assertIsChecked();
581 return *getStorage();
582 }
583
584private:
585 template <class T1>
586 static bool compareThisIfSameType(const T1 &a, const T1 &b) {
587 return &a == &b;
588 }
589
590 template <class T1, class T2>
591 static bool compareThisIfSameType(const T1 &a, const T2 &b) {
592 return false;
593 }
594
595 template <class OtherT> void moveConstruct(Expected<OtherT> &&Other) {
596 HasError = Other.HasError;
597#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
598 Unchecked = true;
599 Other.Unchecked = false;
600#endif
601
602 if (!HasError)
603 new (getStorage()) storage_type(std::move(*Other.getStorage()));
604 else
605 new (getErrorStorage()) error_type(std::move(*Other.getErrorStorage()));
606 }
607
608 template <class OtherT> void moveAssign(Expected<OtherT> &&Other) {
609 assertIsChecked();
610
611 if (compareThisIfSameType(*this, Other))
612 return;
613
614 this->~Expected();
615 new (this) Expected(std::move(Other));
616 }
617
618 pointer toPointer(pointer Val) { return Val; }
619
620 const_pointer toPointer(const_pointer Val) const { return Val; }
621
622 pointer toPointer(wrap *Val) { return &Val->get(); }
623
624 const_pointer toPointer(const wrap *Val) const { return &Val->get(); }
625
626 storage_type *getStorage() {
627 assert(!HasError && "Cannot get value when an error exists!")((!HasError && "Cannot get value when an error exists!"
) ? static_cast<void> (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 627, __PRETTY_FUNCTION__))
;
628 return reinterpret_cast<storage_type *>(TStorage.buffer);
629 }
630
631 const storage_type *getStorage() const {
632 assert(!HasError && "Cannot get value when an error exists!")((!HasError && "Cannot get value when an error exists!"
) ? static_cast<void> (0) : __assert_fail ("!HasError && \"Cannot get value when an error exists!\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 632, __PRETTY_FUNCTION__))
;
633 return reinterpret_cast<const storage_type *>(TStorage.buffer);
634 }
635
636 error_type *getErrorStorage() {
637 assert(HasError && "Cannot get error when a value exists!")((HasError && "Cannot get error when a value exists!"
) ? static_cast<void> (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 637, __PRETTY_FUNCTION__))
;
638 return reinterpret_cast<error_type *>(ErrorStorage.buffer);
639 }
640
641 const error_type *getErrorStorage() const {
642 assert(HasError && "Cannot get error when a value exists!")((HasError && "Cannot get error when a value exists!"
) ? static_cast<void> (0) : __assert_fail ("HasError && \"Cannot get error when a value exists!\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 642, __PRETTY_FUNCTION__))
;
643 return reinterpret_cast<const error_type *>(ErrorStorage.buffer);
644 }
645
646 // Used by ExpectedAsOutParameter to reset the checked flag.
647 void setUnchecked() {
648#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
649 Unchecked = true;
650#endif
651 }
652
653#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
654 LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn))
655 LLVM_ATTRIBUTE_NOINLINE__attribute__((noinline))
656 void fatalUncheckedExpected() const {
657 dbgs() << "Expected<T> must be checked before access or destruction.\n";
658 if (HasError) {
659 dbgs() << "Unchecked Expected<T> contained error:\n";
660 (*getErrorStorage())->log(dbgs());
661 } else
662 dbgs() << "Expected<T> value was in success state. (Note: Expected<T> "
663 "values in success mode must still be checked prior to being "
664 "destroyed).\n";
665 abort();
666 }
667#endif
668
669 void assertIsChecked() {
670#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
671 if (LLVM_UNLIKELY(Unchecked)__builtin_expect((bool)(Unchecked), false))
672 fatalUncheckedExpected();
673#endif
674 }
675
676 union {
677 AlignedCharArrayUnion<storage_type> TStorage;
678 AlignedCharArrayUnion<error_type> ErrorStorage;
679 };
680 bool HasError : 1;
681#if LLVM_ENABLE_ABI_BREAKING_CHECKS1
682 bool Unchecked : 1;
683#endif
684};
685
686/// Report a serious error, calling any installed error handler. See
687/// ErrorHandling.h.
688LLVM_ATTRIBUTE_NORETURN__attribute__((noreturn)) void report_fatal_error(Error Err,
689 bool gen_crash_diag = true);
690
691/// Report a fatal error if Err is a failure value.
692///
693/// This function can be used to wrap calls to fallible functions ONLY when it
694/// is known that the Error will always be a success value. E.g.
695///
696/// @code{.cpp}
697/// // foo only attempts the fallible operation if DoFallibleOperation is
698/// // true. If DoFallibleOperation is false then foo always returns
699/// // Error::success().
700/// Error foo(bool DoFallibleOperation);
701///
702/// cantFail(foo(false));
703/// @endcode
704inline void cantFail(Error Err, const char *Msg = nullptr) {
705 if (Err) {
706 if (!Msg)
707 Msg = "Failure value returned from cantFail wrapped call";
708 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 708)
;
709 }
710}
711
712/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
713/// returns the contained value.
714///
715/// This function can be used to wrap calls to fallible functions ONLY when it
716/// is known that the Error will always be a success value. E.g.
717///
718/// @code{.cpp}
719/// // foo only attempts the fallible operation if DoFallibleOperation is
720/// // true. If DoFallibleOperation is false then foo always returns an int.
721/// Expected<int> foo(bool DoFallibleOperation);
722///
723/// int X = cantFail(foo(false));
724/// @endcode
725template <typename T>
726T cantFail(Expected<T> ValOrErr, const char *Msg = nullptr) {
727 if (ValOrErr)
728 return std::move(*ValOrErr);
729 else {
730 if (!Msg)
731 Msg = "Failure value returned from cantFail wrapped call";
732 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 732)
;
733 }
734}
735
736/// Report a fatal error if ValOrErr is a failure value, otherwise unwraps and
737/// returns the contained reference.
738///
739/// This function can be used to wrap calls to fallible functions ONLY when it
740/// is known that the Error will always be a success value. E.g.
741///
742/// @code{.cpp}
743/// // foo only attempts the fallible operation if DoFallibleOperation is
744/// // true. If DoFallibleOperation is false then foo always returns a Bar&.
745/// Expected<Bar&> foo(bool DoFallibleOperation);
746///
747/// Bar &X = cantFail(foo(false));
748/// @endcode
749template <typename T>
750T& cantFail(Expected<T&> ValOrErr, const char *Msg = nullptr) {
751 if (ValOrErr)
752 return *ValOrErr;
753 else {
754 if (!Msg)
755 Msg = "Failure value returned from cantFail wrapped call";
756 llvm_unreachable(Msg)::llvm::llvm_unreachable_internal(Msg, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 756)
;
757 }
758}
759
760/// Helper for testing applicability of, and applying, handlers for
761/// ErrorInfo types.
762template <typename HandlerT>
763class ErrorHandlerTraits
764 : public ErrorHandlerTraits<decltype(
765 &std::remove_reference<HandlerT>::type::operator())> {};
766
767// Specialization functions of the form 'Error (const ErrT&)'.
768template <typename ErrT> class ErrorHandlerTraits<Error (&)(ErrT &)> {
769public:
770 static bool appliesTo(const ErrorInfoBase &E) {
771 return E.template isA<ErrT>();
772 }
773
774 template <typename HandlerT>
775 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
776 assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast
<void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 776, __PRETTY_FUNCTION__))
;
777 return H(static_cast<ErrT &>(*E));
778 }
779};
780
781// Specialization functions of the form 'void (const ErrT&)'.
782template <typename ErrT> class ErrorHandlerTraits<void (&)(ErrT &)> {
783public:
784 static bool appliesTo(const ErrorInfoBase &E) {
785 return E.template isA<ErrT>();
786 }
787
788 template <typename HandlerT>
789 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
790 assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast
<void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 790, __PRETTY_FUNCTION__))
;
791 H(static_cast<ErrT &>(*E));
792 return Error::success();
793 }
794};
795
796/// Specialization for functions of the form 'Error (std::unique_ptr<ErrT>)'.
797template <typename ErrT>
798class ErrorHandlerTraits<Error (&)(std::unique_ptr<ErrT>)> {
799public:
800 static bool appliesTo(const ErrorInfoBase &E) {
801 return E.template isA<ErrT>();
802 }
803
804 template <typename HandlerT>
805 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
806 assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast
<void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 806, __PRETTY_FUNCTION__))
;
807 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
808 return H(std::move(SubE));
809 }
810};
811
812/// Specialization for functions of the form 'void (std::unique_ptr<ErrT>)'.
813template <typename ErrT>
814class ErrorHandlerTraits<void (&)(std::unique_ptr<ErrT>)> {
815public:
816 static bool appliesTo(const ErrorInfoBase &E) {
817 return E.template isA<ErrT>();
818 }
819
820 template <typename HandlerT>
821 static Error apply(HandlerT &&H, std::unique_ptr<ErrorInfoBase> E) {
822 assert(appliesTo(*E) && "Applying incorrect handler")((appliesTo(*E) && "Applying incorrect handler") ? static_cast
<void> (0) : __assert_fail ("appliesTo(*E) && \"Applying incorrect handler\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 822, __PRETTY_FUNCTION__))
;
823 std::unique_ptr<ErrT> SubE(static_cast<ErrT *>(E.release()));
824 H(std::move(SubE));
825 return Error::success();
826 }
827};
828
829// Specialization for member functions of the form 'RetT (const ErrT&)'.
830template <typename C, typename RetT, typename ErrT>
831class ErrorHandlerTraits<RetT (C::*)(ErrT &)>
832 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
833
834// Specialization for member functions of the form 'RetT (const ErrT&) const'.
835template <typename C, typename RetT, typename ErrT>
836class ErrorHandlerTraits<RetT (C::*)(ErrT &) const>
837 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
838
839// Specialization for member functions of the form 'RetT (const ErrT&)'.
840template <typename C, typename RetT, typename ErrT>
841class ErrorHandlerTraits<RetT (C::*)(const ErrT &)>
842 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
843
844// Specialization for member functions of the form 'RetT (const ErrT&) const'.
845template <typename C, typename RetT, typename ErrT>
846class ErrorHandlerTraits<RetT (C::*)(const ErrT &) const>
847 : public ErrorHandlerTraits<RetT (&)(ErrT &)> {};
848
849/// Specialization for member functions of the form
850/// 'RetT (std::unique_ptr<ErrT>)'.
851template <typename C, typename RetT, typename ErrT>
852class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>)>
853 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
854
855/// Specialization for member functions of the form
856/// 'RetT (std::unique_ptr<ErrT>) const'.
857template <typename C, typename RetT, typename ErrT>
858class ErrorHandlerTraits<RetT (C::*)(std::unique_ptr<ErrT>) const>
859 : public ErrorHandlerTraits<RetT (&)(std::unique_ptr<ErrT>)> {};
860
861inline Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload) {
862 return Error(std::move(Payload));
863}
864
865template <typename HandlerT, typename... HandlerTs>
866Error handleErrorImpl(std::unique_ptr<ErrorInfoBase> Payload,
867 HandlerT &&Handler, HandlerTs &&... Handlers) {
868 if (ErrorHandlerTraits<HandlerT>::appliesTo(*Payload))
869 return ErrorHandlerTraits<HandlerT>::apply(std::forward<HandlerT>(Handler),
870 std::move(Payload));
871 return handleErrorImpl(std::move(Payload),
872 std::forward<HandlerTs>(Handlers)...);
873}
874
875/// Pass the ErrorInfo(s) contained in E to their respective handlers. Any
876/// unhandled errors (or Errors returned by handlers) are re-concatenated and
877/// returned.
878/// Because this function returns an error, its result must also be checked
879/// or returned. If you intend to handle all errors use handleAllErrors
880/// (which returns void, and will abort() on unhandled errors) instead.
881template <typename... HandlerTs>
882Error handleErrors(Error E, HandlerTs &&... Hs) {
883 if (!E)
19
Taking false branch
884 return Error::success();
885
886 std::unique_ptr<ErrorInfoBase> Payload = E.takePayload();
887
888 if (Payload->isA<ErrorList>()) {
20
Assuming the condition is true
21
Taking true branch
889 ErrorList &List = static_cast<ErrorList &>(*Payload);
890 Error R;
891 for (auto &P : List.Payloads)
892 R = ErrorList::join(
22
Calling 'ErrorList::join'
893 std::move(R),
894 handleErrorImpl(std::move(P), std::forward<HandlerTs>(Hs)...));
895 return R;
896 }
897
898 return handleErrorImpl(std::move(Payload), std::forward<HandlerTs>(Hs)...);
899}
900
901/// Behaves the same as handleErrors, except that by contract all errors
902/// *must* be handled by the given handlers (i.e. there must be no remaining
903/// errors after running the handlers, or llvm_unreachable is called).
904template <typename... HandlerTs>
905void handleAllErrors(Error E, HandlerTs &&... Handlers) {
906 cantFail(handleErrors(std::move(E), std::forward<HandlerTs>(Handlers)...));
18
Calling 'handleErrors<(lambda at /build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h:983:35)>'
907}
908
909/// Check that E is a non-error, then drop it.
910/// If E is an error, llvm_unreachable will be called.
911inline void handleAllErrors(Error E) {
912 cantFail(std::move(E));
913}
914
915/// Handle any errors (if present) in an Expected<T>, then try a recovery path.
916///
917/// If the incoming value is a success value it is returned unmodified. If it
918/// is a failure value then it the contained error is passed to handleErrors.
919/// If handleErrors is able to handle the error then the RecoveryPath functor
920/// is called to supply the final result. If handleErrors is not able to
921/// handle all errors then the unhandled errors are returned.
922///
923/// This utility enables the follow pattern:
924///
925/// @code{.cpp}
926/// enum FooStrategy { Aggressive, Conservative };
927/// Expected<Foo> foo(FooStrategy S);
928///
929/// auto ResultOrErr =
930/// handleExpected(
931/// foo(Aggressive),
932/// []() { return foo(Conservative); },
933/// [](AggressiveStrategyError&) {
934/// // Implicitly conusme this - we'll recover by using a conservative
935/// // strategy.
936/// });
937///
938/// @endcode
939template <typename T, typename RecoveryFtor, typename... HandlerTs>
940Expected<T> handleExpected(Expected<T> ValOrErr, RecoveryFtor &&RecoveryPath,
941 HandlerTs &&... Handlers) {
942 if (ValOrErr)
943 return ValOrErr;
944
945 if (auto Err = handleErrors(ValOrErr.takeError(),
946 std::forward<HandlerTs>(Handlers)...))
947 return std::move(Err);
948
949 return RecoveryPath();
950}
951
952/// Log all errors (if any) in E to OS. If there are any errors, ErrorBanner
953/// will be printed before the first one is logged. A newline will be printed
954/// after each error.
955///
956/// This function is compatible with the helpers from Support/WithColor.h. You
957/// can pass any of them as the OS. Please consider using them instead of
958/// including 'error: ' in the ErrorBanner.
959///
960/// This is useful in the base level of your program to allow clean termination
961/// (allowing clean deallocation of resources, etc.), while reporting error
962/// information to the user.
963void logAllUnhandledErrors(Error E, raw_ostream &OS, Twine ErrorBanner = {});
964
965/// Write all error messages (if any) in E to a string. The newline character
966/// is used to separate error messages.
967inline std::string toString(Error E) {
968 SmallVector<std::string, 2> Errors;
969 handleAllErrors(std::move(E), [&Errors](const ErrorInfoBase &EI) {
970 Errors.push_back(EI.message());
971 });
972 return join(Errors.begin(), Errors.end(), "\n");
973}
974
975/// Consume a Error without doing anything. This method should be used
976/// only where an error can be considered a reasonable and expected return
977/// value.
978///
979/// Uses of this method are potentially indicative of design problems: If it's
980/// legitimate to do nothing while processing an "error", the error-producer
981/// might be more clearly refactored to return an Optional<T>.
982inline void consumeError(Error Err) {
983 handleAllErrors(std::move(Err), [](const ErrorInfoBase &) {});
17
Calling 'handleAllErrors<(lambda at /build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h:983:35)>'
984}
985
986/// Helper for converting an Error to a bool.
987///
988/// This method returns true if Err is in an error state, or false if it is
989/// in a success state. Puts Err in a checked state in both cases (unlike
990/// Error::operator bool(), which only does this for success states).
991inline bool errorToBool(Error Err) {
992 bool IsError = static_cast<bool>(Err);
993 if (IsError)
994 consumeError(std::move(Err));
995 return IsError;
996}
997
998/// Helper for Errors used as out-parameters.
999///
1000/// This helper is for use with the Error-as-out-parameter idiom, where an error
1001/// is passed to a function or method by reference, rather than being returned.
1002/// In such cases it is helpful to set the checked bit on entry to the function
1003/// so that the error can be written to (unchecked Errors abort on assignment)
1004/// and clear the checked bit on exit so that clients cannot accidentally forget
1005/// to check the result. This helper performs these actions automatically using
1006/// RAII:
1007///
1008/// @code{.cpp}
1009/// Result foo(Error &Err) {
1010/// ErrorAsOutParameter ErrAsOutParam(&Err); // 'Checked' flag set
1011/// // <body of foo>
1012/// // <- 'Checked' flag auto-cleared when ErrAsOutParam is destructed.
1013/// }
1014/// @endcode
1015///
1016/// ErrorAsOutParameter takes an Error* rather than Error& so that it can be
1017/// used with optional Errors (Error pointers that are allowed to be null). If
1018/// ErrorAsOutParameter took an Error reference, an instance would have to be
1019/// created inside every condition that verified that Error was non-null. By
1020/// taking an Error pointer we can just create one instance at the top of the
1021/// function.
1022class ErrorAsOutParameter {
1023public:
1024 ErrorAsOutParameter(Error *Err) : Err(Err) {
1025 // Raise the checked bit if Err is success.
1026 if (Err)
1027 (void)!!*Err;
1028 }
1029
1030 ~ErrorAsOutParameter() {
1031 // Clear the checked bit.
1032 if (Err && !*Err)
1033 *Err = Error::success();
1034 }
1035
1036private:
1037 Error *Err;
1038};
1039
1040/// Helper for Expected<T>s used as out-parameters.
1041///
1042/// See ErrorAsOutParameter.
1043template <typename T>
1044class ExpectedAsOutParameter {
1045public:
1046 ExpectedAsOutParameter(Expected<T> *ValOrErr)
1047 : ValOrErr(ValOrErr) {
1048 if (ValOrErr)
1049 (void)!!*ValOrErr;
1050 }
1051
1052 ~ExpectedAsOutParameter() {
1053 if (ValOrErr)
1054 ValOrErr->setUnchecked();
1055 }
1056
1057private:
1058 Expected<T> *ValOrErr;
1059};
1060
1061/// This class wraps a std::error_code in a Error.
1062///
1063/// This is useful if you're writing an interface that returns a Error
1064/// (or Expected) and you want to call code that still returns
1065/// std::error_codes.
1066class ECError : public ErrorInfo<ECError> {
1067 friend Error errorCodeToError(std::error_code);
1068
1069public:
1070 void setErrorCode(std::error_code EC) { this->EC = EC; }
1071 std::error_code convertToErrorCode() const override { return EC; }
1072 void log(raw_ostream &OS) const override { OS << EC.message(); }
1073
1074 // Used by ErrorInfo::classID.
1075 static char ID;
1076
1077protected:
1078 ECError() = default;
1079 ECError(std::error_code EC) : EC(EC) {}
1080
1081 std::error_code EC;
1082};
1083
1084/// The value returned by this function can be returned from convertToErrorCode
1085/// for Error values where no sensible translation to std::error_code exists.
1086/// It should only be used in this situation, and should never be used where a
1087/// sensible conversion to std::error_code is available, as attempts to convert
1088/// to/from this error will result in a fatal error. (i.e. it is a programmatic
1089///error to try to convert such a value).
1090std::error_code inconvertibleErrorCode();
1091
1092/// Helper for converting an std::error_code to a Error.
1093Error errorCodeToError(std::error_code EC);
1094
1095/// Helper for converting an ECError to a std::error_code.
1096///
1097/// This method requires that Err be Error() or an ECError, otherwise it
1098/// will trigger a call to abort().
1099std::error_code errorToErrorCode(Error Err);
1100
1101/// Convert an ErrorOr<T> to an Expected<T>.
1102template <typename T> Expected<T> errorOrToExpected(ErrorOr<T> &&EO) {
1103 if (auto EC = EO.getError())
1104 return errorCodeToError(EC);
1105 return std::move(*EO);
1106}
1107
1108/// Convert an Expected<T> to an ErrorOr<T>.
1109template <typename T> ErrorOr<T> expectedToErrorOr(Expected<T> &&E) {
1110 if (auto Err = E.takeError())
1111 return errorToErrorCode(std::move(Err));
1112 return std::move(*E);
1113}
1114
1115/// This class wraps a string in an Error.
1116///
1117/// StringError is useful in cases where the client is not expected to be able
1118/// to consume the specific error message programmatically (for example, if the
1119/// error message is to be presented to the user).
1120///
1121/// StringError can also be used when additional information is to be printed
1122/// along with a error_code message. Depending on the constructor called, this
1123/// class can either display:
1124/// 1. the error_code message (ECError behavior)
1125/// 2. a string
1126/// 3. the error_code message and a string
1127///
1128/// These behaviors are useful when subtyping is required; for example, when a
1129/// specific library needs an explicit error type. In the example below,
1130/// PDBError is derived from StringError:
1131///
1132/// @code{.cpp}
1133/// Expected<int> foo() {
1134/// return llvm::make_error<PDBError>(pdb_error_code::dia_failed_loading,
1135/// "Additional information");
1136/// }
1137/// @endcode
1138///
1139class StringError : public ErrorInfo<StringError> {
1140public:
1141 static char ID;
1142
1143 // Prints EC + S and converts to EC
1144 StringError(std::error_code EC, const Twine &S = Twine());
1145
1146 // Prints S and converts to EC
1147 StringError(const Twine &S, std::error_code EC);
1148
1149 void log(raw_ostream &OS) const override;
1150 std::error_code convertToErrorCode() const override;
1151
1152 const std::string &getMessage() const { return Msg; }
1153
1154private:
1155 std::string Msg;
1156 std::error_code EC;
1157 const bool PrintMsgOnly = false;
1158};
1159
1160/// Create formatted StringError object.
1161template <typename... Ts>
1162Error createStringError(std::error_code EC, char const *Fmt,
1163 const Ts &... Vals) {
1164 std::string Buffer;
1165 raw_string_ostream Stream(Buffer);
1166 Stream << format(Fmt, Vals...);
1167 return make_error<StringError>(Stream.str(), EC);
1168}
1169
1170Error createStringError(std::error_code EC, char const *Msg);
1171
1172/// This class wraps a filename and another Error.
1173///
1174/// In some cases, an error needs to live along a 'source' name, in order to
1175/// show more detailed information to the user.
1176class FileError final : public ErrorInfo<FileError> {
1177
1178 friend Error createFileError(std::string, Error);
1179
1180public:
1181 void log(raw_ostream &OS) const override {
1182 assert(Err && !FileName.empty() && "Trying to log after takeError().")((Err && !FileName.empty() && "Trying to log after takeError()."
) ? static_cast<void> (0) : __assert_fail ("Err && !FileName.empty() && \"Trying to log after takeError().\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 1182, __PRETTY_FUNCTION__))
;
1183 OS << "'" << FileName << "': ";
1184 Err->log(OS);
1185 }
1186
1187 Error takeError() { return Error(std::move(Err)); }
1188
1189 std::error_code convertToErrorCode() const override;
1190
1191 // Used by ErrorInfo::classID.
1192 static char ID;
1193
1194private:
1195 FileError(std::string F, std::unique_ptr<ErrorInfoBase> E) {
1196 assert(E && "Cannot create FileError from Error success value.")((E && "Cannot create FileError from Error success value."
) ? static_cast<void> (0) : __assert_fail ("E && \"Cannot create FileError from Error success value.\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 1196, __PRETTY_FUNCTION__))
;
1197 assert(!F.empty() &&((!F.empty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.empty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 1198, __PRETTY_FUNCTION__))
1198 "The file name provided to FileError must not be empty.")((!F.empty() && "The file name provided to FileError must not be empty."
) ? static_cast<void> (0) : __assert_fail ("!F.empty() && \"The file name provided to FileError must not be empty.\""
, "/build/llvm-toolchain-snapshot-8~svn350071/include/llvm/Support/Error.h"
, 1198, __PRETTY_FUNCTION__))
;
1199 FileName = F;
1200 Err = std::move(E);
1201 }
1202
1203 static Error build(std::string F, Error E) {
1204 return Error(std::unique_ptr<FileError>(new FileError(F, E.takePayload())));
1205 }
1206
1207 std::string FileName;
1208 std::unique_ptr<ErrorInfoBase> Err;
1209};
1210
1211/// Concatenate a source file path and/or name with an Error. The resulting
1212/// Error is unchecked.
1213inline Error createFileError(std::string F, Error E) {
1214 return FileError::build(F, std::move(E));
1215}
1216
1217Error createFileError(std::string F, ErrorSuccess) = delete;
1218
1219/// Helper for check-and-exit error handling.
1220///
1221/// For tool use only. NOT FOR USE IN LIBRARY CODE.
1222///
1223class ExitOnError {
1224public:
1225 /// Create an error on exit helper.
1226 ExitOnError(std::string Banner = "", int DefaultErrorExitCode = 1)
1227 : Banner(std::move(Banner)),
1228 GetExitCode([=](const Error &) { return DefaultErrorExitCode; }) {}
1229
1230 /// Set the banner string for any errors caught by operator().
1231 void setBanner(std::string Banner) { this->Banner = std::move(Banner); }
1232
1233 /// Set the exit-code mapper function.
1234 void setExitCodeMapper(std::function<int(const Error &)> GetExitCode) {
1235 this->GetExitCode = std::move(GetExitCode);
1236 }
1237
1238 /// Check Err. If it's in a failure state log the error(s) and exit.
1239 void operator()(Error Err) const { checkError(std::move(Err)); }
1240
1241 /// Check E. If it's in a success state then return the contained value. If
1242 /// it's in a failure state log the error(s) and exit.
1243 template <typename T> T operator()(Expected<T> &&E) const {
1244 checkError(E.takeError());
1245 return std::move(*E);
1246 }
1247
1248 /// Check E. If it's in a success state then return the contained reference. If
1249 /// it's in a failure state log the error(s) and exit.
1250 template <typename T> T& operator()(Expected<T&> &&E) const {
1251 checkError(E.takeError());
1252 return *E;
1253 }
1254
1255private:
1256 void checkError(Error Err) const {
1257 if (Err) {
1258 int ExitCode = GetExitCode(Err);
1259 logAllUnhandledErrors(std::move(Err), errs(), Banner);
1260 exit(ExitCode);
1261 }
1262 }
1263
1264 std::string Banner;
1265 std::function<int(const Error &)> GetExitCode;
1266};
1267
1268/// Conversion from Error to LLVMErrorRef for C error bindings.
1269inline LLVMErrorRef wrap(Error Err) {
1270 return reinterpret_cast<LLVMErrorRef>(Err.takePayload().release());
1271}
1272
1273/// Conversion from LLVMErrorRef to Error for C error bindings.
1274inline Error unwrap(LLVMErrorRef ErrRef) {
1275 return Error(std::unique_ptr<ErrorInfoBase>(
1276 reinterpret_cast<ErrorInfoBase *>(ErrRef)));
1277}
1278
1279} // end namespace llvm
1280
1281#endif // LLVM_SUPPORT_ERROR_H