Stacks for getFile() from PCH files look like so:
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
* frame #0: 0x000000010005a1fb
clang-cl`clang::FileManager::getFile(this=0x00000001106111f0,
Filename=(Data =
"/Users/thakis/src/chrome/src/out/gnwin/../../third_party/skia/include/core/SkPoint3.h",
Length = 85), openFile=false, CacheFailure=true) at FileManager.cpp:187
frame #1: 0x0000000103c44b2e
clang-cl`clang::ASTReader::getInputFile(this=0x000000011104c200,
F=0x000000011104fc00, ID=3, Complain=true) at ASTReader.cpp:2120
frame #2: 0x0000000103c5173b
clang-cl`clang::ASTReader::ReadControlBlock(this=0x000000011104c200,
F=0x000000011104fc00, Loaded=0x00007fff5fbfa130,
ImportedBy=0x0000000000000000, ClientLoadCapabilities=0) at
ASTReader.cpp:2398
frame #3: 0x0000000103c5381b
clang-cl`clang::ASTReader::ReadASTCore(this=0x000000011104c200,
FileName=(Data =
"obj/third_party/blink/renderer/core/layout/layout_cc.pch", Length = 56),
Type=MK_PCH, ImportLoc=(ID = 0), ImportedBy=0x0000000000000000,
Loaded=0x00007fff5fbfa130, ExpectedSize=0, ExpectedModTime=0,
ExpectedSignature=ASTFileSignature @ 0x00007fff5fbf9d58,
ClientLoadCapabilities=0) at ASTReader.cpp:4208
frame #4: 0x0000000103c5fe95
clang-cl`clang::ASTReader::ReadAST(this=0x000000011104c200, FileName=(Data
= "obj/third_party/blink/renderer/core/layout/layout_cc.pch", Length = 56),
Type=MK_PCH, ImportLoc=(ID = 0), ClientLoadCapabilities=0,
Imported=0x0000000000000000) at ASTReader.cpp:3883
frame #5: 0x0000000100a49542
clang-cl`clang::CompilerInstance::createPCHExternalASTSource(Path=(Data =
"obj/third_party/blink/renderer/core/layout/layout_cc.pch", Length = 56),
Sysroot=(Data = "/", Length = 1), DisablePCHValidation=false,
AllowPCHWithCompilerErrors=false, PP=0x0000000111037e18,
Context=0x0000000111042200, PCHContainerRdr=0x000000011060d2b0,
Extensions=ArrayRef<std::__1::shared_ptr<clang::ModuleFileExtension> > @
0x00007fff5fbfa430, DependencyFile=0x0000000000000000,
DependencyCollectors=ArrayRef<std::__1::shared_ptr<clang::DependencyCollector>
> @ 0x00007fff5fbfa448, DeserializationListener=0x0000000000000000,
OwnDeserializationListener=false, Preamble=false,
UseGlobalModuleIndex=true) at CompilerInstance.cpp:532
frame #6: 0x0000000100a4909b
clang-cl`clang::CompilerInstance::createPCHExternalASTSource(this=0x000000011060d000,
Path=(Data = "obj/third_party/blink/renderer/core/layout/layout_cc.pch",
Length = 56), DisablePCHValidation=false, AllowPCHWithCompilerErrors=false,
DeserializationListener=0x0000000000000000,
OwnDeserializationListener=false) at CompilerInstance.cpp:490
frame #7: 0x0000000100ada301
clang-cl`clang::FrontendAction::BeginSourceFile(this=0x000000011060eee0,
CI=0x000000011060d000, RealInput=0x0000000110614a60) at
FrontendAction.cpp:859
frame #8: 0x0000000100a4cdf8
clang-cl`clang::CompilerInstance::ExecuteAction(this=0x000000011060d000,
Act=0x000000011060eee0) at CompilerInstance.cpp:953
frame #9: 0x0000000100b5c21f
clang-cl`clang::ExecuteCompilerInvocation(Clang=0x000000011060d000) at
ExecuteCompilerInvocation.cpp:267
frame #10: 0x0000000100001ac9 clang-cl`cc1_main(Argv=ArrayRef<const
char *> @ 0x00007fff5fbfb4c8,
Argv0="../../../../llvm-mono-2/out/gn/bin/clang-cl",
MainAddr=0x0000000100028110) at cc1_main.cpp:218
frame #11: 0x000000010002999f
clang-cl`ExecuteCC1Tool(argv=ArrayRef<const char *> @ 0x00007fff5fbfba78,
Tool=(Data = "", Length = 0)) at driver.cpp:309
frame #12: 0x0000000100028a81 clang-cl`main(argc_=409,
argv_=0x00007fff5fbfd170) at driver.cpp:381
frame #13: 0x00007fffb015c235 libdyld.dylib`start + 1
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
* frame #0: 0x000000010005a1fb
clang-cl`clang::FileManager::getFile(this=0x00000001106111f0,
Filename=(Data =
"/Users/thakis/src/chrome/src/out/gnwin/../../third_party/skia/include/core/SkPoint3.h",
Length = 85), openFile=false, CacheFailure=true) at FileManager.cpp:187
frame #1: 0x0000000103c476e3
clang-cl`clang::serialization::reader::HeaderFileInfoTrait::EqualKey(this=0x00007fff5fbf5f80,
Key=0x00007fff5fbf6068)::$_1::operator()(clang::serialization::reader::HeaderFileInfoTrait::internal_key_type
const&) const at ASTReader.cpp:1723
frame #2: 0x0000000103c4759f
clang-cl`clang::serialization::reader::HeaderFileInfoTrait::EqualKey(this=0x0000000113a16c88,
a=0x00007fff5fbf6068, b=0x00007fff5fbf6138) at ASTReader.cpp:1726
frame #3: 0x0000000103cd5c1e
clang-cl`llvm::OnDiskChainedHashTable<clang::serialization::reader::HeaderFileInfoTrait>::find_hashed(this=0x0000000113a16c70,
IKey=0x00007fff5fbf6138, KeyHash=986574196, InfoPtr=0x0000000113a16c88) at
OnDiskHashTable.h:390
frame #4: 0x0000000103cd59b8
clang-cl`llvm::OnDiskChainedHashTable<clang::serialization::reader::HeaderFileInfoTrait>::find(this=0x0000000113a16c70,
EKey=0x00007fff5fbf6538, InfoPtr=0x0000000000000000) at
OnDiskHashTable.h:345
frame #5: 0x0000000103cd58b9 clang-cl`(anonymous
namespace)::HeaderFileInfoVisitor::operator(this=0x00007fff5fbf6538,
M=0x000000011104fc00)(clang::serialization::ModuleFile&) at
ASTReader.cpp:5683
frame #6: 0x0000000103cd5850 clang-cl`bool llvm::function_ref<bool
(clang::serialization::ModuleFile&)>::callback_fn<(anonymous
namespace)::HeaderFileInfoVisitor>(callable=140734799766840,
params=0x000000011104fc00) at STLExtras.h:125
frame #7: 0x0000000103e338cc clang-cl`llvm::function_ref<bool
(clang::serialization::ModuleFile&)>::operator(this=0x00007fff5fbf64a0,
params=0x000000011104fc00)(clang::serialization::ModuleFile&) const at
STLExtras.h:142
frame #8: 0x0000000103e33507
clang-cl`clang::serialization::ModuleManager::visit(this=0x000000011104c298,
Visitor=function_ref<bool (clang::serialization::ModuleFile &)> @
0x00007fff5fbf64a0, ModuleFilesHit=0x0000000000000000)>,
llvm::SmallPtrSetImpl<clang::serialization::ModuleFile*>*) at
ModuleManager.cpp:411
frame #9: 0x0000000103c69ade
clang-cl`clang::ASTReader::GetHeaderFileInfo(this=0x000000011104c200,
FE=0x0000000113a00030) at ASTReader.cpp:5698
frame #10: 0x0000000103c69d03 clang-cl`non-virtual thunk to
clang::ASTReader::GetHeaderFileInfo(this=0x000000011104c200,
FE=0x0000000113a00030) at ASTReader.cpp:0
frame #11: 0x0000000102ca607c
clang-cl`clang::HeaderSearch::getExistingFileInfo(this=0x0000000111036e00,
FE=0x0000000113a00030, WantExternal=true) const at HeaderSearch.cpp:1140
frame #12: 0x0000000102ca6faf
clang-cl`clang::HeaderSearch::findModuleForHeader(this=0x0000000111036e00,
File=0x0000000113a00030, AllowTextual=true) const at HeaderSearch.cpp:1334
frame #13: 0x0000000102ca700a
clang-cl`suggestModule(HS=0x0000000111036e00, File=0x0000000113a00030,
RequestingModule=0x0000000000000000, SuggestedModule=0x00007fff5fbf9020) at
HeaderSearch.cpp:1343
frame #14: 0x0000000102ca1dd2
clang-cl`clang::HeaderSearch::findUsableModuleForHeader(this=0x0000000111036e00,
File=0x0000000113a00030, Root=0x00000001106126d0,
RequestingModule=0x0000000000000000, SuggestedModule=0x00007fff5fbf9020,
IsSystemHeaderDir=false) at HeaderSearch.cpp:1367
frame #15: 0x0000000102ca1cee
clang-cl`clang::HeaderSearch::getFileAndSuggestModule(this=0x0000000111036e00,
FileName=(Data = "../../third_party/skia/include/core/SkPoint3.h", Length =
46), IncludeLoc=(ID = 4980551), Dir=0x00000001106126d0,
IsSystemHeaderDir=false, RequestingModule=0x0000000000000000,
SuggestedModule=0x00007fff5fbf9020) at HeaderSearch.cpp:318
frame #16: 0x0000000102ca20ad
clang-cl`clang::DirectoryLookup::LookupFile(this=0x000000011060f1e0,
Filename=0x00007fff5fbf7c20, HS=0x0000000111036e00, IncludeLoc=(ID =
4980551), SearchPath=0x00007fff5fbf9438, RelativePath=0x00007fff5fbf9028,
RequestingModule=0x0000000000000000, SuggestedModule=0x00007fff5fbf9020,
InUserSpecifiedSystemFramework=0x00007fff5fbf763f,
HasBeenMapped=0x00007fff5fbf763e, MappedName=0x00007fff5fbf7640) const at
HeaderSearch.cpp:357
frame #17: 0x0000000102ca3e15
clang-cl`clang::HeaderSearch::LookupFile(this=0x0000000111036e00,
Filename=(Data = "third_party/skia/include/core/SkPoint3.h", Length = 40),
IncludeLoc=(ID = 4980551), isAngled=false, FromDir=0x0000000000000000,
CurDir=0x00007fff5fbf9848, Includers=ArrayRef<std::__1::pair<const
clang::FileEntry *, const clang::DirectoryEntry *> > @ 0x00007fff5fbf7c78,
SearchPath=0x00007fff5fbf9438, RelativePath=0x00007fff5fbf9028,
RequestingModule=0x0000000000000000, SuggestedModule=0x00007fff5fbf9020,
IsMapped=0x00007fff5fbf9857, SkipCache=false, BuildSystemModule=false) at
HeaderSearch.cpp:854
frame #18: 0x0000000102d01858
clang-cl`clang::Preprocessor::LookupFile(this=0x0000000111037e18,
FilenameLoc=(ID = 4980551), Filename=(Data =
"third_party/skia/include/core/SkPoint3.h", Length = 40), isAngled=false,
FromDir=0x0000000000000000, FromFile=0x0000000000000000,
CurDir=0x00007fff5fbf9848, SearchPath=0x00007fff5fbf9438,
RelativePath=0x00007fff5fbf9028, SuggestedModule=0x00007fff5fbf9020,
IsMapped=0x00007fff5fbf9857, SkipCache=false) at PPDirectives.cpp:740
frame #19: 0x0000000102d03384
clang-cl`clang::Preprocessor::HandleIncludeDirective(this=0x0000000111037e18,
HashLoc=(ID = 4980542), IncludeTok=0x000000011080ac10,
LookupFrom=0x0000000000000000, LookupFromFile=0x0000000000000000,
isImport=false) at PPDirectives.cpp:1773
frame #20: 0x0000000102d05dfa
clang-cl`clang::Preprocessor::HandleDirective(this=0x0000000111037e18,
Result=0x000000011080ac10) at PPDirectives.cpp:942
frame #21: 0x0000000102cbfedf
clang-cl`clang::Lexer::LexTokenInternal(this=0x000000011a6f1430,
Result=0x000000011080ac10, TokAtPhysicalStartOfLine=true) at Lexer.cpp:3931
frame #22: 0x0000000102cbc178
clang-cl`clang::Lexer::Lex(this=0x000000011a6f1430,
Result=0x000000011080ac10) at Lexer.cpp:3152
frame #23: 0x0000000102d54d8b
clang-cl`clang::Preprocessor::Lex(this=0x0000000111037e18,
Result=0x000000011080ac10) at Preprocessor.cpp:868
frame #24: 0x0000000102f235b9
clang-cl`clang::Parser::ConsumeBrace(this=0x000000011080ac00) at
Parser.h:563
frame #25: 0x0000000102f2a1da
clang-cl`clang::BalancedDelimiterTracker::consumeClose(this=0x00007fff5fbfa560)
at RAIIObjectsForParser.h:429
frame #26: 0x0000000102e788a5
clang-cl`clang::Parser::ParseInnerNamespace(this=0x000000011080ac00,
InnerNSs=0x00007fff5fbfa6e0, index=0, InlineLoc=0x00007fff5fbfa7a0,
attrs=0x00007fff5fbfa6b8, Tracker=0x00007fff5fbfa560) at
ParseDeclCXX.cpp:250
frame #27: 0x0000000102e77d96
clang-cl`clang::Parser::ParseNamespace(this=0x000000011080ac00,
Context=FileContext, DeclEnd=0x00007fff5fbfaa70, InlineLoc=(ID = 0)) at
ParseDeclCXX.cpp:223
frame #28: 0x0000000102e5aee9
clang-cl`clang::Parser::ParseDeclaration(this=0x000000011080ac00,
Context=FileContext, DeclEnd=0x00007fff5fbfaa70, attrs=0x00007fff5fbfac40)
at ParseDecl.cpp:1714
frame #29: 0x0000000102f25d83
clang-cl`clang::Parser::ParseExternalDeclaration(this=0x000000011080ac00,
attrs=0x00007fff5fbfac40, DS=0x0000000000000000) at Parser.cpp:788
frame #30: 0x0000000102f24ec6
clang-cl`clang::Parser::ParseTopLevelDecl(this=0x000000011080ac00,
Result=0x00007fff5fbfad78) at Parser.cpp:609
frame #31: 0x0000000102e4a036
clang-cl`clang::ParseAST(S=0x00000001108fba00, PrintStats=true,
SkipFunctionBodies=false) at ParseAST.cpp:156
frame #32: 0x0000000100add2d2
clang-cl`clang::ASTFrontendAction::ExecuteAction(this=0x000000011060eee0)
at FrontendAction.cpp:1035
frame #33: 0x00000001004f6c7d
clang-cl`clang::CodeGenAction::ExecuteAction(this=0x000000011060eee0) at
CodeGenAction.cpp:1047
frame #34: 0x0000000100adc8e0
clang-cl`clang::FrontendAction::Execute(this=0x000000011060eee0) at
FrontendAction.cpp:934
frame #35: 0x0000000100a4ce0e
clang-cl`clang::CompilerInstance::ExecuteAction(this=0x000000011060d000,
Act=0x000000011060eee0) at CompilerInstance.cpp:954
frame #36: 0x0000000100b5c21f
clang-cl`clang::ExecuteCompilerInvocation(Clang=0x000000011060d000) at
ExecuteCompilerInvocation.cpp:267
frame #37: 0x0000000100001ac9 clang-cl`cc1_main(Argv=ArrayRef<const
char *> @ 0x00007fff5fbfb4c8,
Argv0="../../../../llvm-mono-2/out/gn/bin/clang-cl",
MainAddr=0x0000000100028110) at cc1_main.cpp:218
frame #38: 0x000000010002999f
clang-cl`ExecuteCC1Tool(argv=ArrayRef<const char *> @ 0x00007fff5fbfba78,
Tool=(Data = "", Length = 0)) at driver.cpp:309
frame #39: 0x0000000100028a81 clang-cl`main(argc_=409,
argv_=0x00007fff5fbfd170) at driver.cpp:381
frame #40: 0x00007fffb015c235 libdyld.dylib`start + 1
For regular includes they look like so:
(lldb) bt
* thread #1, queue = 'com.apple.main-thread', stop reason = breakpoint 1.1
* frame #0: 0x0000000100059d29
clang-cl`clang::FileManager::getStatValue(this=0x0000000110611270,
Path=(Data =
"../../third_party/blink/renderer/platform/scheduler/public/scheduling_lifecycle_state.h",
Length = 87), Data=0x00007fff5fbf6640, isFile=true, F=0x00007fff5fbf6680)
at FileManager.cpp:465
frame #1: 0x000000010005a471
clang-cl`clang::FileManager::getFile(this=0x0000000110611270,
Filename=(Data =
"../../third_party/blink/renderer/platform/scheduler/public/scheduling_lifecycle_state.h",
Length = 87), openFile=true, CacheFailure=true) at FileManager.cpp:230
frame #2: 0x0000000102ca1ca2
clang-cl`clang::HeaderSearch::getFileAndSuggestModule(this=0x0000000111036e00,
FileName=(Data =
"../../third_party/blink/renderer/platform/scheduler/public/scheduling_lifecycle_state.h",
Length = 87), IncludeLoc=(ID = 9004850), Dir=0x0000000110502730,
IsSystemHeaderDir=false, RequestingModule=0x0000000000000000,
SuggestedModule=0x00007fff5fbf9030) at HeaderSearch.cpp:313
frame #3: 0x0000000102ca20dd
clang-cl`clang::DirectoryLookup::LookupFile(this=0x0000000110503850,
Filename=0x00007fff5fbf7c30, HS=0x0000000111036e00, IncludeLoc=(ID =
9004850), SearchPath=0x00007fff5fbf9448, RelativePath=0x00007fff5fbf9038,
RequestingModule=0x0000000000000000, SuggestedModule=0x00007fff5fbf9030,
InUserSpecifiedSystemFramework=0x00007fff5fbf764f,
HasBeenMapped=0x00007fff5fbf764e, MappedName=0x00007fff5fbf7650) const at
HeaderSearch.cpp:357
frame #4: 0x0000000102ca3e45
clang-cl`clang::HeaderSearch::LookupFile(this=0x0000000111036e00,
Filename=(Data =
"third_party/blink/renderer/platform/scheduler/public/scheduling_lifecycle_state.h",
Length = 81), IncludeLoc=(ID = 9004850), isAngled=false,
FromDir=0x0000000000000000, CurDir=0x00007fff5fbf9858,
Includers=ArrayRef<std::__1::pair<const clang::FileEntry *, const
clang::DirectoryEntry *> > @ 0x00007fff5fbf7c88,
SearchPath=0x00007fff5fbf9448, RelativePath=0x00007fff5fbf9038,
RequestingModule=0x0000000000000000, SuggestedModule=0x00007fff5fbf9030,
IsMapped=0x00007fff5fbf9867, SkipCache=false, BuildSystemModule=false) at
HeaderSearch.cpp:854
frame #5: 0x0000000102d01888
clang-cl`clang::Preprocessor::LookupFile(this=0x0000000111037e18,
FilenameLoc=(ID = 9004850), Filename=(Data =
"third_party/blink/renderer/platform/scheduler/public/scheduling_lifecycle_state.h",
Length = 81), isAngled=false, FromDir=0x0000000000000000,
FromFile=0x0000000000000000, CurDir=0x00007fff5fbf9858,
SearchPath=0x00007fff5fbf9448, RelativePath=0x00007fff5fbf9038,
SuggestedModule=0x00007fff5fbf9030, IsMapped=0x00007fff5fbf9867,
SkipCache=false) at PPDirectives.cpp:740
frame #6: 0x0000000102d033b4
clang-cl`clang::Preprocessor::HandleIncludeDirective(this=0x0000000111037e18,
HashLoc=(ID = 9004841), IncludeTok=0x0000000115068810,
LookupFrom=0x0000000000000000, LookupFromFile=0x0000000000000000,
isImport=false) at PPDirectives.cpp:1773
frame #7: 0x0000000102d05e2a
clang-cl`clang::Preprocessor::HandleDirective(this=0x0000000111037e18,
Result=0x0000000115068810) at PPDirectives.cpp:942
frame #8: 0x0000000102cbff0f
clang-cl`clang::Lexer::LexTokenInternal(this=0x000000011d98b010,
Result=0x0000000115068810, TokAtPhysicalStartOfLine=true) at Lexer.cpp:3931
frame #9: 0x0000000102cbc1a8
clang-cl`clang::Lexer::Lex(this=0x000000011d98b010,
Result=0x0000000115068810) at Lexer.cpp:3152
frame #10: 0x0000000102d54dbb
clang-cl`clang::Preprocessor::Lex(this=0x0000000111037e18,
Result=0x0000000115068810) at Preprocessor.cpp:868
frame #11: 0x0000000102f235e9
clang-cl`clang::Parser::ConsumeBrace(this=0x0000000115068800) at
Parser.h:563
frame #12: 0x0000000102f2a20a
clang-cl`clang::BalancedDelimiterTracker::consumeClose(this=0x00007fff5fbfa570)
at RAIIObjectsForParser.h:429
frame #13: 0x0000000102e788d5
clang-cl`clang::Parser::ParseInnerNamespace(this=0x0000000115068800,
InnerNSs=0x00007fff5fbfa6f0, index=0, InlineLoc=0x00007fff5fbfa7b0,
attrs=0x00007fff5fbfa6c8, Tracker=0x00007fff5fbfa570) at
ParseDeclCXX.cpp:250
frame #14: 0x0000000102e77dc6
clang-cl`clang::Parser::ParseNamespace(this=0x0000000115068800,
Context=FileContext, DeclEnd=0x00007fff5fbfaa80, InlineLoc=(ID = 0)) at
ParseDeclCXX.cpp:223
frame #15: 0x0000000102e5af19
clang-cl`clang::Parser::ParseDeclaration(this=0x0000000115068800,
Context=FileContext, DeclEnd=0x00007fff5fbfaa80, attrs=0x00007fff5fbfac50)
at ParseDecl.cpp:1714
frame #16: 0x0000000102f25db3
clang-cl`clang::Parser::ParseExternalDeclaration(this=0x0000000115068800,
attrs=0x00007fff5fbfac50, DS=0x0000000000000000) at Parser.cpp:788
frame #17: 0x0000000102f24ef6
clang-cl`clang::Parser::ParseTopLevelDecl(this=0x0000000115068800,
Result=0x00007fff5fbfad88) at Parser.cpp:609
frame #18: 0x0000000102e4a066
clang-cl`clang::ParseAST(S=0x0000000115061a00, PrintStats=false,
SkipFunctionBodies=false) at ParseAST.cpp:156
frame #19: 0x0000000100add302
clang-cl`clang::ASTFrontendAction::ExecuteAction(this=0x000000011060ef90)
at FrontendAction.cpp:1035
frame #20: 0x00000001004f6cad
clang-cl`clang::CodeGenAction::ExecuteAction(this=0x000000011060ef90) at
CodeGenAction.cpp:1047
frame #21: 0x0000000100adc910
clang-cl`clang::FrontendAction::Execute(this=0x000000011060ef90) at
FrontendAction.cpp:934
frame #22: 0x0000000100a4ce3e
clang-cl`clang::CompilerInstance::ExecuteAction(this=0x000000011060d050,
Act=0x000000011060ef90) at CompilerInstance.cpp:954
frame #23: 0x0000000100b5c24f
clang-cl`clang::ExecuteCompilerInvocation(Clang=0x000000011060d050) at
ExecuteCompilerInvocation.cpp:267
frame #24: 0x0000000100001b19 clang-cl`cc1_main(Argv=ArrayRef<const
char *> @ 0x00007fff5fbfb4d8,
Argv0="../../../../llvm-mono-2/out/gn/bin/clang-cl",
MainAddr=0x0000000100028160) at cc1_main.cpp:218
frame #25: 0x00000001000299ef
clang-cl`ExecuteCC1Tool(argv=ArrayRef<const char *> @ 0x00007fff5fbfba88,
Tool=(Data = "", Length = 0)) at driver.cpp:309
frame #26: 0x0000000100028ad1 clang-cl`main(argc_=408,
argv_=0x00007fff5fbfd188) at driver.cpp:381
frame #27: 0x00007fffb015c235 libdyld.dylib`start + 1
frame #28: 0x00007fffb015c235 libdyld.dylib`start + 1
On Wed, Jan 23, 2019 at 12:10 PM Sam McCall <sammcc...@google.com> wrote:
> Thanks! given that we don't see an earlier stat, I guess these files were
> being treated as virtual (file metadata deserialized from PCH). Previously
> despite the open=true these never actually got opened, and that worked fine.
>
> I'm away from my computer but will verify later tonight or in the morning
> (CET) and try to find a fix. If it's not obvious, we should revert the
> patch at least on the release branch.
>
> A stack trace at the relevant breakpoint might well be useful - can't
> remember if there are lots of entry points here.
>
> Cheers, Sam
>
> On Wed, Jan 23, 2019, 16:38 Nico Weber <tha...@chromium.org wrote:
>
>> With your patch reverted locally, at the same breakpoint I instead get
>>
>> $ lsof -p 95842 | wc -l
>> 94
>>
>> So your patch seems to increase number of open file handles by ~260%.
>>
>> On Wed, Jan 23, 2019 at 10:27 AM Nico Weber <tha...@chromium.org> wrote:
>>
>>> On Wed, Jan 23, 2019 at 9:54 AM Sam McCall <sammcc...@google.com> wrote:
>>>
>>>> (Email is better than IRC if that's OK - I don't know this code that
>>>> well so it takes me a while).
>>>>
>>>> Thanks, that's definitely interesting and not what I expected. I
>>>> thought every call sequence r347205 changed the behavior of would have
>>>> resulted in two calls to getStatValue().
>>>> I guess the "pch"/"main" output is printed before the corresponding
>>>> lines in run.sh?
>>>>
>>>
>>> Correct.
>>>
>>>
>>>> Weird that we don't get any output from building the PCH, but I don't
>>>> know well how PCH builds work.
>>>>
>>>> > It looks like FS->getCurrentWorkingDirectory() is set
>>>> yet FileSystemOpts.WorkingDir.empty() is also true. Is that expected?
>>>> I think so. The FileManager and the VFS each have their own concept of
>>>> working directory, I guess for historical reasons.
>>>> Making use of the VFS one but not the FileManager one seems reasonable.
>>>>
>>>> So the weirdness is that FileSystemStatCache::get() is returning true
>>>> (i.e. file doesn't exist), when the file does exist.
>>>> Possibilities:
>>>> 1) we're serving this result from the FileSystemStatCache (and maybe
>>>> it's being poisoned in a PCH-related way somehow). Except as far as I can
>>>> tell, FileSystemStatCache is always null (FileManager::setStateCache has no
>>>> callers).
>>>> 2) the FS.openFileForRead call failed (ultimately ::open, if FS is the
>>>> real FS)
>>>> 3) the OwnedFile->status() call failed (ultimately ::fstat)
>>>> 4) I'm misreading the code somehow
>>>>
>>>
>>> ::open() fails with errno == 24, EMFILE.
>>>
>>> This log statement here:
>>>
>>> diff --git a/clang/lib/Basic/FileSystemStatCache.cpp
>>> b/clang/lib/Basic/FileSystemStatCache.cpp
>>> index d29ebb750fc..63fc4780237 100644
>>> --- a/clang/lib/Basic/FileSystemStatCache.cpp
>>> +++ b/clang/lib/Basic/FileSystemStatCache.cpp
>>> @@ -70,9 +70,13 @@ bool FileSystemStatCache::get(StringRef Path,
>>> FileData &Data, bool isFile,
>>> //
>>> // Because of this, check to see if the file exists with 'open'.
>>> If the
>>> // open succeeds, use fstat to get the stat info.
>>> - auto OwnedFile = FS.openFileForRead(Path);
>>> + llvm::ErrorOr<std::unique_ptr<llvm::vfs::File>> OwnedFile =
>>> + FS.openFileForRead(Path);
>>>
>>> if (!OwnedFile) {
>>> +if (Path.endswith("scheduling_lifecycle_state.h")) {
>>> +fprintf(stderr, "hmm failed %s\n",
>>> OwnedFile.getError().message().c_str());
>>> +}
>>> // If the open fails, our "stat" fails.
>>> R = CacheMissing;
>>> } else {
>>>
>>>
>>> causes clang to print "hmm failed Too many open files". That path should
>>> maybe check if `OwnedFile.getError().value() == EMFILE &&
>>> OwnedFile.getError().category() == std::generic_category()` on mac and
>>> abort or diag or something more visible.
>>>
>>> `ulimit -n` on macOS is pretty small -- do you see how your patch could
>>> cause clang to keep more file handles open?
>>>
>>> Here's how many files clang had open when I had a breakpoint in that
>>> error path:
>>>
>>> $ lsof -p 91890 | wc -l
>>> 343
>>>
>>>
>>>
>>>>
>>>> Could you find out which of these is going on? Either running in a
>>>> debugger or adding some similar printfs to FileSystemStatCache::get()
>>>> should be doable.
>>>> I'm also going to try to work out how the patch could have affected
>>>> this, but new vs correct much easier for me to compare than new vs old...
>>>>
>>>
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