[modules] Rationalize the behavior of Decl::declarationReplaces, and in

particular don't assume that two declarations of the same kind in the same
context are declaring the same entity. That's not true when the same name is
declared multiple times as internal-linkage symbols within a module.
(getCanonicalDecl is cheap now, so we can just use it here.)

llvm-svn: 251898

2 files changed, 3 insertions, 3 deletions

diff --git a/clang/lib/Sema/SemaDecl.cpp b/clang/lib/Sema/SemaDecl.cpp
index 622ff1ebbce..e188094f90a 100644
--- a/clang/lib/Sema/SemaDecl.cpp
+++ b/clang/lib/Sema/SemaDecl.cpp
@@ -3352,7 +3352,7 @@ void Sema::MergeVarDecl(VarDecl *New, LookupResult &Previous) {
       !TemplateParameterListsAreEqual(NewTemplate->getTemplateParameters(),
                                       OldTemplate->getTemplateParameters(),
                                       /*Complain=*/true, TPL_TemplateMatch))
-    return;
+    return New->setInvalidDecl();
 
   // C++ [class.mem]p1:
   //   A member shall not be declared twice in the member-specification [...]
@@ -8220,7 +8220,7 @@ bool Sema::CheckFunctionDeclaration(Scope *S, FunctionDecl *NewFD,
     // there's no more work to do here; we'll just add the new
     // function to the scope.
     if (!AllowOverloadingOfFunction(Previous, Context)) {
-      NamedDecl *Candidate = Previous.getFoundDecl();
+      NamedDecl *Candidate = Previous.getRepresentativeDecl();
       if (shouldLinkPossiblyHiddenDecl(Candidate, NewFD)) {
         Redeclaration = true;
         OldDecl = Candidate;
diff --git a/clang/lib/Sema/SemaLookup.cpp b/clang/lib/Sema/SemaLookup.cpp
index 6fbe0da8c90..0ba34ea8ef2 100644
--- a/clang/lib/Sema/SemaLookup.cpp
+++ b/clang/lib/Sema/SemaLookup.cpp
@@ -474,7 +474,7 @@ void LookupResult::resolveKind() {
     D = cast<NamedDecl>(D->getCanonicalDecl());
 
     // Ignore an invalid declaration unless it's the only one left.
-    if (D->isInvalidDecl() && I < N-1) {
+    if (D->isInvalidDecl() && !(I == 0 && N == 1)) {
       Decls[I] = Decls[--N];
       continue;
     }