[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/Serialization/ASTReader.cpp b/clang/lib/Serialization/ASTReader.cpp
index f56afeb..84286ca 100644
--- a/clang/lib/Serialization/ASTReader.cpp
+++ b/clang/lib/Serialization/ASTReader.cpp
@@ -704,6 +704,17 @@
// Compute the #include and #include_macros lines we need.
for (unsigned I = 0, N = ExistingPPOpts.Includes.size(); I != N; ++I) {
StringRef File = ExistingPPOpts.Includes[I];
+
+ if (!ExistingPPOpts.ImplicitPCHInclude.empty() &&
+ !ExistingPPOpts.PCHThroughHeader.empty()) {
+ // In case the through header is an include, we must add all the includes
+ // to the predefines so the start point can be determined.
+ SuggestedPredefines += "#include \"";
+ SuggestedPredefines += File;
+ SuggestedPredefines += "\"\n";
+ continue;
+ }
+
if (File == ExistingPPOpts.ImplicitPCHInclude)
continue;