Made changes to how 'struct'/'class' mismatches are handled in -Wmismatched-tags.

- Removed fix-it hints from template instaniations since changes to the
templates are rarely helpful.
- Changed the caret in template instaniations from the class/struct name to the
class/struct keyword, matching the other warnings.
- Do not offer fix-it hints when multiple declarations disagree.  Warnings are
still given.
- Once a definition is found, offer a fix-it hint to all previous declarations
with wrong tag.
- Declarations that disagree with a previous definition will get a fix-it hint
to change the declaration.

llvm-svn: 132831

1 files changed, 6 insertions, 4 deletions

diff --git a/clang/lib/Sema/SemaTemplate.cpp b/clang/lib/Sema/SemaTemplate.cpp
index 8213f3266f1..5d4caacd812 100644
--- a/clang/lib/Sema/SemaTemplate.cpp
+++ b/clang/lib/Sema/SemaTemplate.cpp
@@ -920,7 +920,8 @@ Sema::CheckClassTemplate(Scope *S, unsigned TagSpec, TagUseKind TUK,
     //   the class-key shall agree in kind with the original class
     //   template declaration (7.1.5.3).
     RecordDecl *PrevRecordDecl = PrevClassTemplate->getTemplatedDecl();
-    if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind, KWLoc, *Name)) {
+    if (!isAcceptableTagRedeclaration(PrevRecordDecl, Kind,
+                                      TUK == TUK_Definition,  KWLoc, *Name)) {
       Diag(KWLoc, diag::err_use_with_wrong_tag)
         << Name
         << FixItHint::CreateReplacement(KWLoc, PrevRecordDecl->getKindName());
@@ -2130,7 +2131,8 @@ TypeResult Sema::ActOnTagTemplateIdType(TagUseKind TUK,
     IdentifierInfo *Id = D->getIdentifier();
     assert(Id && "templated class must have an identifier");
     
-    if (!isAcceptableTagRedeclaration(D, TagKind, TagLoc, *Id)) {
+    if (!isAcceptableTagRedeclaration(D, TagKind, TUK == TUK_Definition,
+                                      TagLoc, *Id)) {
       Diag(TagLoc, diag::err_use_with_wrong_tag)
         << Result
         << FixItHint::CreateReplacement(SourceRange(TagLoc), D->getKindName());
@@ -4775,7 +4777,7 @@ Sema::ActOnClassTemplateSpecialization(Scope *S, unsigned TagSpec,
   TagTypeKind Kind = TypeWithKeyword::getTagTypeKindForTypeSpec(TagSpec);
   assert(Kind != TTK_Enum && "Invalid enum tag in class template spec!");
   if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
-                                    Kind, KWLoc,
+                                    Kind, TUK == TUK_Definition, KWLoc,
                                     *ClassTemplate->getIdentifier())) {
     Diag(KWLoc, diag::err_use_with_wrong_tag)
       << ClassTemplate
@@ -5746,7 +5748,7 @@ Sema::ActOnExplicitInstantiation(Scope *S,
   assert(Kind != TTK_Enum &&
          "Invalid enum tag in class template explicit instantiation!");
   if (!isAcceptableTagRedeclaration(ClassTemplate->getTemplatedDecl(),
-                                    Kind, KWLoc,
+                                    Kind, /*isDefinition*/false, KWLoc,
                                     *ClassTemplate->getIdentifier())) {
     Diag(KWLoc, diag::err_use_with_wrong_tag)
       << ClassTemplate