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.



git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@132831 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 9 insertions, 3 deletions

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index 9b6eaf3c18..17356b963d 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -2268,9 +2268,15 @@ def err_nested_redefinition : Error<"nested redefinition of %0">;
 def err_use_with_wrong_tag : Error<
   "use of %0 with tag type that does not match previous declaration">;
 def warn_struct_class_tag_mismatch : Warning<
-    "%select{struct|class}0 %select{|template}1 %2 was previously declared "
-    "as a %select{class|struct}0 %select{|template}1">,
+    "%select{struct|class}0%select{| template}1 %2 was previously declared "
+    "as a %select{class|struct}0%select{| template}1">,
     InGroup<MismatchedTags>, DefaultIgnore;
+def warn_struct_class_previous_tag_mismatch : Warning<
+    "%2 defined as a %select{struct|class}0%select{| template}1 here but "
+    "previously declared as a %select{class|struct}0%select{| template}1">,
+     InGroup<MismatchedTags>, DefaultIgnore;
+def note_struct_class_suggestion : Note<
+    "did you mean %select{struct|class}0 here?">;
 def ext_forward_ref_enum : Extension<
   "ISO C forbids forward references to 'enum' types">;
 def err_forward_ref_enum : Error<
diff --git a/include/clang/Sema/Sema.h b/include/clang/Sema/Sema.h
index ee2bc39ea4..ac449cfb30 100644
--- a/include/clang/Sema/Sema.h
+++ b/include/clang/Sema/Sema.h
@@ -1103,7 +1103,7 @@ public:
                                        RecordDecl *Record);
 
   bool isAcceptableTagRedeclaration(const TagDecl *Previous,
-                                    TagTypeKind NewTag,
+                                    TagTypeKind NewTag, bool isDefinition,
                                     SourceLocation NewTagLoc,
                                     const IdentifierInfo &Name);