[clang-cl, PCH] Implement support for MS-style PCH through headers
Implement support for MS-style PCH through headers.
This enables support for /Yc and /Yu where the through header is either
on the command line or included in the source. It replaces the current
support the requires the header also be specified with /FI.
This change adds a -cc1 option -pch-through-header that is used to either
start or stop compilation during PCH create or use.
When creating a PCH, the compilation ends after compilation of the through
header.
When using a PCH, tokens are skipped until after the through header is seen.
Patch By: mikerice
Differential Revision: https://reviews.llvm.org/D46652
llvm-svn: 336379
diff --git a/clang/lib/Frontend/CompilerInstance.cpp b/clang/lib/Frontend/CompilerInstance.cpp
index c4863d6..5727aae 100644
--- a/clang/lib/Frontend/CompilerInstance.cpp
+++ b/clang/lib/Frontend/CompilerInstance.cpp
@@ -853,36 +853,7 @@
// Figure out where to get and map in the main file.
if (InputFile != "-") {
- const FileEntry *File;
- if (Opts.FindPchSource.empty()) {
- File = FileMgr.getFile(InputFile, /*OpenFile=*/true);
- } else {
- // When building a pch file in clang-cl mode, the .h file is built as if
- // it was included by a cc file. Since the driver doesn't know about
- // all include search directories, the frontend must search the input
- // file through HeaderSearch here, as if it had been included by the
- // cc file at Opts.FindPchSource.
- const FileEntry *FindFile = FileMgr.getFile(Opts.FindPchSource);
- if (!FindFile) {
- Diags.Report(diag::err_fe_error_reading) << Opts.FindPchSource;
- return false;
- }
- const DirectoryLookup *UnusedCurDir;
- SmallVector<std::pair<const FileEntry *, const DirectoryEntry *>, 16>
- Includers;
- Includers.push_back(std::make_pair(FindFile, FindFile->getDir()));
- File = HS->LookupFile(InputFile, SourceLocation(), /*isAngled=*/false,
- /*FromDir=*/nullptr,
- /*CurDir=*/UnusedCurDir, Includers,
- /*SearchPath=*/nullptr,
- /*RelativePath=*/nullptr,
- /*RequestingModule=*/nullptr,
- /*SuggestedModule=*/nullptr, /*IsMapped=*/nullptr,
- /*SkipCache=*/true);
- // Also add the header to /showIncludes output.
- if (File)
- DepOpts.ShowIncludesPretendHeader = File->getName();
- }
+ const FileEntry *File = FileMgr.getFile(InputFile, /*OpenFile=*/true);
if (!File) {
Diags.Report(diag::err_fe_error_reading) << InputFile;
return false;