[clang] Pass VFS into ASTUnit::LoadFromASTFile() (llvm#159166)

This PR makes the `VFS` parameter to `ASTUnit::LoadFromASTFile()` required and explicit, rather than silently defaulting to the real file system. This makes it easy to correctly propagate the fully-configured VFS and load any input files like the rest of the compiler does.

Author: jansvoboda11

clang/include/clang/Frontend/ASTUnit.h

@@ -706,16 +706,15 @@ class ASTUnit {
  /// \returns - The initialized ASTUnit or null if the AST failed to load.
  static std::unique_ptr<ASTUnit> LoadFromASTFile(
  StringRef Filename, const PCHContainerReader &PCHContainerRdr,
- WhatToLoad ToLoad, std::shared_ptr<DiagnosticOptions> DiagOpts,
+ WhatToLoad ToLoad, IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS,
+ std::shared_ptr<DiagnosticOptions> DiagOpts,
  IntrusiveRefCntPtr<DiagnosticsEngine> Diags,
  const FileSystemOptions &FileSystemOpts,
  const HeaderSearchOptions &HSOpts, const LangOptions *LangOpts = nullptr,
  bool OnlyLocalDecls = false,
  CaptureDiagsKind CaptureDiagnostics = CaptureDiagsKind::None,
  bool AllowASTWithCompilerErrors = false,
- bool UserFilesAreVolatile = false,
- IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS =
- llvm::vfs::getRealFileSystem());
+ bool UserFilesAreVolatile = false);
 
 private:
  /// Helper function for \c LoadFromCompilerInvocation() and

clang/lib/CrossTU/CrossTranslationUnit.cpp

@@ -578,8 +578,8 @@ CrossTranslationUnitContext::ASTLoader::loadFromDump(StringRef ASTDumpPath) {
  new DiagnosticsEngine(DiagID, *DiagOpts, DiagClient));
  return ASTUnit::LoadFromASTFile(
  ASTDumpPath, CI.getPCHContainerOperations()->getRawReader(),
- ASTUnit::LoadEverything, DiagOpts, Diags, CI.getFileSystemOpts(),
- CI.getHeaderSearchOpts());
+ ASTUnit::LoadEverything, CI.getVirtualFileSystemPtr(), DiagOpts, Diags,
+ CI.getFileSystemOpts(), CI.getHeaderSearchOpts());
 }
 
 /// Load the AST from a source-file, which is supposed to be located inside the

clang/lib/Frontend/ASTMerge.cpp

@@ -47,7 +47,8 @@ void ASTMergeAction::ExecuteAction() {
  /*ShouldOwnClient=*/true));
  std::unique_ptr<ASTUnit> Unit = ASTUnit::LoadFromASTFile(
  ASTFiles[I], CI.getPCHContainerReader(), ASTUnit::LoadEverything,
- nullptr, Diags, CI.getFileSystemOpts(), CI.getHeaderSearchOpts());
+ CI.getVirtualFileSystemPtr(), nullptr, Diags, CI.getFileSystemOpts(),
+ CI.getHeaderSearchOpts());
 
  if (!Unit)
  continue;

clang/lib/Frontend/ASTUnit.cpp

@@ -799,12 +799,13 @@ void ASTUnit::ConfigureDiags(IntrusiveRefCntPtr<DiagnosticsEngine> Diags,
 
 std::unique_ptr<ASTUnit> ASTUnit::LoadFromASTFile(
  StringRef Filename, const PCHContainerReader &PCHContainerRdr,
- WhatToLoad ToLoad, std::shared_ptr<DiagnosticOptions> DiagOpts,
+ WhatToLoad ToLoad, IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS,
+ std::shared_ptr<DiagnosticOptions> DiagOpts,
  IntrusiveRefCntPtr<DiagnosticsEngine> Diags,
  const FileSystemOptions &FileSystemOpts, const HeaderSearchOptions &HSOpts,
  const LangOptions *LangOpts, bool OnlyLocalDecls,
  CaptureDiagsKind CaptureDiagnostics, bool AllowASTWithCompilerErrors,
- bool UserFilesAreVolatile, IntrusiveRefCntPtr<llvm::vfs::FileSystem> VFS) {
+ bool UserFilesAreVolatile) {
  std::unique_ptr<ASTUnit> AST(new ASTUnit(true));
 
  // Recover resources if we crash before exiting this method.

clang/lib/Frontend/FrontendAction.cpp

@@ -904,7 +904,8 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
 
  std::unique_ptr<ASTUnit> AST = ASTUnit::LoadFromASTFile(
  InputFile, CI.getPCHContainerReader(), ASTUnit::LoadPreprocessorOnly,
- nullptr, ASTDiags, CI.getFileSystemOpts(), CI.getHeaderSearchOpts());
+ CI.getVirtualFileSystemPtr(), nullptr, ASTDiags, CI.getFileSystemOpts(),
+ CI.getHeaderSearchOpts());
  if (!AST)
  return false;
 
@@ -971,9 +972,9 @@ bool FrontendAction::BeginSourceFile(CompilerInstance &CI,
  StringRef InputFile = Input.getFile();
 
  std::unique_ptr<ASTUnit> AST = ASTUnit::LoadFromASTFile(
- InputFile, CI.getPCHContainerReader(), ASTUnit::LoadEverything, nullptr,
- Diags, CI.getFileSystemOpts(), CI.getHeaderSearchOpts(),
- &CI.getLangOpts());
+ InputFile, CI.getPCHContainerReader(), ASTUnit::LoadEverything,
+ CI.getVirtualFileSystemPtr(), nullptr, Diags, CI.getFileSystemOpts(),
+ CI.getHeaderSearchOpts(), &CI.getLangOpts());
 
  if (!AST)
  return false;

clang/tools/c-index-test/core_main.cpp

@@ -369,12 +369,13 @@ static bool printSourceSymbolsFromModule(StringRef modulePath,
 
  HeaderSearchOptions HSOpts;
 
+ auto VFS = llvm::vfs::getRealFileSystem();
+
  auto DiagOpts = std::make_shared<DiagnosticOptions>();
  IntrusiveRefCntPtr<DiagnosticsEngine> Diags =
- CompilerInstance::createDiagnostics(*llvm::vfs::getRealFileSystem(),
- *DiagOpts);
+ CompilerInstance::createDiagnostics(*VFS, *DiagOpts);
  std::unique_ptr<ASTUnit> AU = ASTUnit::LoadFromASTFile(
- modulePath, *pchRdr, ASTUnit::LoadASTOnly, DiagOpts, Diags,
+ modulePath, *pchRdr, ASTUnit::LoadASTOnly, VFS, DiagOpts, Diags,
  FileSystemOpts, HSOpts, /*LangOpts=*/nullptr,
  /*OnlyLocalDecls=*/true, CaptureDiagsKind::None,
  /*AllowASTWithCompilerErrors=*/true,

clang/tools/clang-extdef-mapping/ClangExtDefMapGen.cpp

@@ -158,8 +158,8 @@ static bool HandleAST(StringRef AstPath) {
 
  std::unique_ptr<ASTUnit> Unit = ASTUnit::LoadFromASTFile(
  AstPath, CI->getPCHContainerOperations()->getRawReader(),
- ASTUnit::LoadASTOnly, DiagOpts, DiagEngine, CI->getFileSystemOpts(),
- CI->getHeaderSearchOpts());
+ ASTUnit::LoadASTOnly, CI->getVirtualFileSystemPtr(), DiagOpts, DiagEngine,
+ CI->getFileSystemOpts(), CI->getHeaderSearchOpts());
 
  if (!Unit)
  return false;

clang/tools/libclang/CIndex.cpp

@@ -4243,13 +4243,14 @@ enum CXErrorCode clang_createTranslationUnit2(CXIndex CIdx,
  FileSystemOptions FileSystemOpts;
  HeaderSearchOptions HSOpts;
 
+ auto VFS = llvm::vfs::getRealFileSystem();
+
  auto DiagOpts = std::make_shared<DiagnosticOptions>();
  IntrusiveRefCntPtr<DiagnosticsEngine> Diags =
- CompilerInstance::createDiagnostics(*llvm::vfs::getRealFileSystem(),
- *DiagOpts);
+ CompilerInstance::createDiagnostics(*VFS, *DiagOpts);
  std::unique_ptr<ASTUnit> AU = ASTUnit::LoadFromASTFile(
  ast_filename, CXXIdx->getPCHContainerOperations()->getRawReader(),
- ASTUnit::LoadEverything, DiagOpts, Diags, FileSystemOpts, HSOpts,
+ ASTUnit::LoadEverything, VFS, DiagOpts, Diags, FileSystemOpts, HSOpts,
  /*LangOpts=*/nullptr, CXXIdx->getOnlyLocalDecls(), CaptureDiagsKind::All,
  /*AllowASTWithCompilerErrors=*/true,
  /*UserFilesAreVolatile=*/true);

clang/unittests/Frontend/ASTUnitTest.cpp

@@ -97,7 +97,8 @@ TEST_F(ASTUnitTest, SaveLoadPreservesLangOptionsInPrintingPolicy) {
 
  std::unique_ptr<ASTUnit> AU = ASTUnit::LoadFromASTFile(
  ASTFileName, PCHContainerOps->getRawReader(), ASTUnit::LoadEverything,
- DiagOpts, Diags, FileSystemOptions(), HSOpts);
+ llvm::vfs::getRealFileSystem(), DiagOpts, Diags, FileSystemOptions(),
+ HSOpts);
 
  if (!AU)
  FAIL() << "failed to load ASTUnit";