Introduce the notion of excluded headers into the module map

description. Previously, one could emulate this behavior by placing
the header in an always-unavailable submodule, but Argyrios guilted me
into expressing this idea properly.

llvm-svn: 165921

1 files changed, 12 insertions, 0 deletions

diff --git a/clang/lib/Serialization/ASTWriter.cpp b/clang/lib/Serialization/ASTWriter.cpp
index 2fbe4bf6a33..d04753a037d 100644
--- a/clang/lib/Serialization/ASTWriter.cpp
+++ b/clang/lib/Serialization/ASTWriter.cpp
@@ -1983,6 +1983,11 @@ void ASTWriter::WriteSubmodules(Module *WritingModule) {
   Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Feature
   unsigned RequiresAbbrev = Stream.EmitAbbrev(Abbrev);
 
+  Abbrev = new BitCodeAbbrev();
+  Abbrev->Add(BitCodeAbbrevOp(SUBMODULE_EXCLUDED_HEADER));
+  Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // Name
+  unsigned ExcludedHeaderAbbrev = Stream.EmitAbbrev(Abbrev);
+
   // Write the submodule metadata block.
   RecordData Record;
   Record.push_back(getNumberOfModules(WritingModule));
@@ -2044,6 +2049,13 @@ void ASTWriter::WriteSubmodules(Module *WritingModule) {
       Stream.EmitRecordWithBlob(HeaderAbbrev, Record, 
                                 Mod->Headers[I]->getName());
     }
+    // Emit the excluded headers.
+    for (unsigned I = 0, N = Mod->ExcludedHeaders.size(); I != N; ++I) {
+      Record.clear();
+      Record.push_back(SUBMODULE_EXCLUDED_HEADER);
+      Stream.EmitRecordWithBlob(ExcludedHeaderAbbrev, Record, 
+                                Mod->ExcludedHeaders[I]->getName());
+    }
     for (unsigned I = 0, N = Mod->TopHeaders.size(); I != N; ++I) {
       Record.clear();
       Record.push_back(SUBMODULE_TOPHEADER);