Make tag declarations redeclarable. This change has three purposes:
1) Allow the Index library (and any other interested client) to walk
the set of declarations for a given tag (enum, union, class,
whatever). At the moment, this information is not readily available.
2) Reduce our dependence on TagDecl::TypeForDecl being mapped down
to a TagType (for which getDecl() will return the tag definition, if
one exists). This property won't exist for class template partial
specializations.
3) Make the canonical declaration of a TagDecl actually canonical,
e.g., so that it does not change when the tag is defined.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@77523 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Frontend/PCHReaderDecl.cpp b/lib/Frontend/PCHReaderDecl.cpp
index 99a1a16..65da7dc 100644
--- a/lib/Frontend/PCHReaderDecl.cpp
+++ b/lib/Frontend/PCHReaderDecl.cpp
@@ -112,6 +112,8 @@
void PCHDeclReader::VisitTagDecl(TagDecl *TD) {
VisitTypeDecl(TD);
+ TD->setPreviousDeclaration(
+ cast_or_null<TagDecl>(Reader.GetDecl(Record[Idx++])));
TD->setTagKind((TagDecl::TagKind)Record[Idx++]);
TD->setDefinition(Record[Idx++]);
TD->setTypedefForAnonDecl(
diff --git a/lib/Frontend/PCHWriterDecl.cpp b/lib/Frontend/PCHWriterDecl.cpp
index 4239798..fd7ea42 100644
--- a/lib/Frontend/PCHWriterDecl.cpp
+++ b/lib/Frontend/PCHWriterDecl.cpp
@@ -109,6 +109,7 @@
void PCHDeclWriter::VisitTagDecl(TagDecl *D) {
VisitTypeDecl(D);
+ Writer.AddDeclRef(D->getPreviousDeclaration(), Record);
Record.push_back((unsigned)D->getTagKind()); // FIXME: stable encoding
Record.push_back(D->isDefinition());
Writer.AddDeclRef(D->getTypedefForAnonDecl(), Record);