[PCH] Mark a PCH file with a flag to indicate if the serialized AST had

compiler errors or not.

-Control whether ASTReader should reject such a PCH by a boolean flag at ASTReader's creation time.
By default, such a PCH file will be rejected with an error when trying to load it.

[libclang] Allow clang_saveTranslationUnit to create a PCH file even if compiler errors
occurred.
-Have libclang API calls accept a PCH that had compiler errors.

The general idea is that we want libclang to stay functional even if a PCH had a compiler error.
rdar://10976363.

llvm-svn: 152192

1 files changed, 7 insertions, 2 deletions

diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp
index 88c1f70021e..4edfbff2888 100644
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -981,6 +981,7 @@ void ASTWriter::WriteMetadata(ASTContext &Context, StringRef isysroot,
   MetaAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 16)); // Clang major
   MetaAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 16)); // Clang minor
   MetaAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Relocatable
+  MetaAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 1)); // Has errors
   MetaAbbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Target triple
   unsigned MetaAbbrevCode = Stream.EmitAbbrev(MetaAbbrev);
 
@@ -991,6 +992,7 @@ void ASTWriter::WriteMetadata(ASTContext &Context, StringRef isysroot,
   Record.push_back(CLANG_VERSION_MAJOR);
   Record.push_back(CLANG_VERSION_MINOR);
   Record.push_back(!isysroot.empty());
+  Record.push_back(ASTHasCompilerErrors);
   const std::string &Triple = Target.getTriple().getTriple();
   Stream.EmitRecordWithBlob(MetaAbbrevCode, Record, Triple);
 
@@ -3115,7 +3117,7 @@ void ASTWriter::SetSelectorOffset(Selector Sel, uint32_t Offset) {
 
 ASTWriter::ASTWriter(llvm::BitstreamWriter &Stream)
   : Stream(Stream), Context(0), PP(0), Chain(0), WritingModule(0),
-    WritingAST(false),
+    WritingAST(false), ASTHasCompilerErrors(false),
     FirstDeclID(NUM_PREDEF_DECL_IDS), NextDeclID(FirstDeclID),
     FirstTypeID(NUM_PREDEF_TYPE_IDS), NextTypeID(FirstTypeID),
     FirstIdentID(NUM_PREDEF_IDENT_IDS), NextIdentID(FirstIdentID), 
@@ -3144,9 +3146,12 @@ ASTWriter::~ASTWriter() {
 
 void ASTWriter::WriteAST(Sema &SemaRef, MemorizeStatCalls *StatCalls,
                          const std::string &OutputFile,
-                         Module *WritingModule, StringRef isysroot) {
+                         Module *WritingModule, StringRef isysroot,
+                         bool hasErrors) {
   WritingAST = true;
   
+  ASTHasCompilerErrors = hasErrors;
+  
   // Emit the file header.
   Stream.Emit((unsigned)'C', 8);
   Stream.Emit((unsigned)'P', 8);