[Modules] Fix an issue where the reconstructed redeclaration chain was incomplete, missing the definition from a module.
-Make sure that a deserialized external decl gets added to the TU scope.
-When associating an identifier with a set of decls, use the most recent local ones,
if they exist, otherwise associating decls from modules (that came after a local one)
will lead to an incomplete reconstructed re-declaration chain.
rdar://13712705
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180634 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Serialization/ASTWriter.cpp b/lib/Serialization/ASTWriter.cpp
index c5a0550..ba53bda 100644
--- a/lib/Serialization/ASTWriter.cpp
+++ b/lib/Serialization/ASTWriter.cpp
@@ -3106,7 +3106,28 @@
for (SmallVector<Decl *, 16>::reverse_iterator D = Decls.rbegin(),
DEnd = Decls.rend();
D != DEnd; ++D)
- clang::io::Emit32(Out, Writer.getDeclID(*D));
+ clang::io::Emit32(Out, Writer.getDeclID(getMostRecentLocalDecl(*D)));
+ }
+
+ /// \brief Returns the most recent local decl or the given decl if there are
+ /// no local ones. The given decl is assumed to be the most recent one.
+ Decl *getMostRecentLocalDecl(Decl *Orig) {
+ // The only way a "from AST file" decl would be more recent from a local one
+ // is if it came from a module.
+ if (!PP.getLangOpts().Modules)
+ return Orig;
+
+ // Look for a local in the decl chain.
+ for (Decl *D = Orig; D; D = D->getPreviousDecl()) {
+ if (!D->isFromASTFile())
+ return D;
+ // If we come up a decl from a (chained-)PCH stop since we won't find a
+ // local one.
+ if (D->getOwningModuleID() == 0)
+ break;
+ }
+
+ return Orig;
}
};
} // end anonymous namespace