When comparing two template template arguments in the template differ, consider

them the same if they are actually the same; having the same name isn't enough.

Similar to r174013, template template arguments were also mistakenly considered
the same when they had the same name but were in different namespaces.
In addition, when printing template template arguments, use the qualified name
if the regular name is the same.

llvm-svn: 174029

1 files changed, 14 insertions, 5 deletions

diff --git a/clang/lib/AST/ASTDiagnostic.cpp b/clang/lib/AST/ASTDiagnostic.cpp
index fb3544f03aa..4f165132a6f 100644
--- a/clang/lib/AST/ASTDiagnostic.cpp
+++ b/clang/lib/AST/ASTDiagnostic.cpp
@@ -894,8 +894,9 @@ class TemplateDiff {
         GetTemplateDecl(FromIter, DefaultTTPD, FromDecl);
         GetTemplateDecl(ToIter, DefaultTTPD, ToDecl);
         Tree.SetNode(FromDecl, ToDecl);
-        Tree.SetSame(FromDecl && ToDecl &&
-                     FromDecl->getIdentifier() == ToDecl->getIdentifier());
+        Tree.SetSame(
+            FromDecl && ToDecl &&
+            FromDecl->getCanonicalDecl() == ToDecl->getCanonicalDecl());
       }
 
       if (!FromIter.isEnd()) ++FromIter;
@@ -1278,21 +1279,29 @@ class TemplateDiff {
   void PrintTemplateTemplate(TemplateDecl *FromTD, TemplateDecl *ToTD,
                              bool FromDefault, bool ToDefault, bool Same) {
     assert((FromTD || ToTD) && "Only one template argument may be missing.");
+
+    std::string FromName = FromTD ? FromTD->getName() : "(no argument)";
+    std::string ToName = ToTD ? ToTD->getName() : "(no argument)";
+    if (FromTD && ToTD && FromName == ToName) {
+      FromName = FromTD->getQualifiedNameAsString();
+      ToName = ToTD->getQualifiedNameAsString();
+    }
+
     if (Same) {
       OS << "template " << FromTD->getNameAsString();
     } else if (!PrintTree) {
       OS << (FromDefault ? "(default) template " : "template ");
       Bold();
-      OS << (FromTD ? FromTD->getNameAsString() : "(no argument)");
+      OS << FromName;
       Unbold();
     } else {
       OS << (FromDefault ? "[(default) template " : "[template ");
       Bold();
-      OS << (FromTD ? FromTD->getNameAsString() : "(no argument)");
+      OS << FromName;
       Unbold();
       OS << " != " << (ToDefault ? "(default) template " : "template ");
       Bold();
-      OS << (ToTD ? ToTD->getNameAsString() : "(no argument)");
+      OS << ToName;
       Unbold();
       OS << ']';
     }