[cfe-commits] r106540 - in /cfe/trunk: include/clang/Basic/DiagnosticSemaKinds.td lib/Sema/SemaDecl.cpp test/SemaCXX/enum.cpp

[Douglas Gregor]

Author: dgregor
Date: Tue Jun 22 09:26:35 2010
New Revision: 106540

URL: http://llvm.org/viewvc/llvm-project?rev=106540&view=rev
Log:
In C++, allow a declaration of an enum to follow a definition of that
enum as a GNU extension.


Modified:
    cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
    cfe/trunk/lib/Sema/SemaDecl.cpp
    cfe/trunk/test/SemaCXX/enum.cpp

Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=106540&r1=106539&r2=106540&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original)
+++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Tue Jun 22 09:26:35 2010
@@ -1722,6 +1722,9 @@
   "ISO C forbids forward references to 'enum' types">;
 def err_forward_ref_enum : Error<
   "ISO C++ forbids forward references to 'enum' types">;
+def ext_forward_ref_enum_def : Extension<
+  "redeclaration of already-defined enum %0 is a GNU extension">, InGroup<GNU>;
+  
 def err_redefinition_of_enumerator : Error<"redefinition of enumerator %0">;
 def err_duplicate_member : Error<"duplicate member %0">;
 def err_misplaced_ivar : Error<

Modified: cfe/trunk/lib/Sema/SemaDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=106540&r1=106539&r2=106540&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaDecl.cpp (original)
+++ cfe/trunk/lib/Sema/SemaDecl.cpp Tue Jun 22 09:26:35 2010
@@ -5401,10 +5401,17 @@
     New = EnumDecl::Create(Context, SearchDC, Loc, Name, KWLoc,
                            cast_or_null<EnumDecl>(PrevDecl));
     // If this is an undefined enum, warn.
-    if (TUK != TUK_Definition && !Invalid)  {
-      unsigned DK = getLangOptions().CPlusPlus? diag::err_forward_ref_enum
-                                              : diag::ext_forward_ref_enum;
-      Diag(Loc, DK);
+    if (TUK != TUK_Definition && !Invalid) {
+      TagDecl *Def;
+      if (PrevDecl && (Def = cast<EnumDecl>(PrevDecl)->getDefinition())) {
+        Diag(Loc, diag::ext_forward_ref_enum_def)
+          << New;
+        Diag(Def->getLocation(), diag::note_previous_definition);
+      } else {
+        Diag(Loc, 
+             getLangOptions().CPlusPlus? diag::err_forward_ref_enum
+                                       : diag::ext_forward_ref_enum);
+      }
     }
   } else {
     // struct/union/class

Modified: cfe/trunk/test/SemaCXX/enum.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/enum.cpp?rev=106540&r1=106539&r2=106540&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/enum.cpp (original)
+++ cfe/trunk/test/SemaCXX/enum.cpp Tue Jun 22 09:26:35 2010
@@ -1,9 +1,11 @@
 // RUN: %clang_cc1 -fsyntax-only -pedantic -std=c++98 -verify -triple x86_64-apple-darwin %s
-enum E {
+enum E { // expected-note{{previous definition is here}}
   Val1,
   Val2
 };
 
+enum E; // expected-warning{{redeclaration of already-defined enum 'E' is a GNU extension}}
+
 int& enumerator_type(int);
 float& enumerator_type(E);