From: Francois Pichet <pichet2000@gmail.com>
Date: Sun, 12 Sep 2010 05:06:55 +0000 (+0000)
Subject: Add basic support for Microsoft enum forward declaration.
X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=8dc3abcc36df883324461daad0c05364158f3cf0;p=clang

Add basic support for Microsoft enum forward declaration.
Assigning an underlying integral type to an enum forward declaration will come in a next patch.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@113716 91177308-0d34-0410-b5e6-96231b3b80d8
---

diff --git a/include/clang/Basic/DiagnosticSemaKinds.td b/include/clang/Basic/DiagnosticSemaKinds.td
index da5ebc2a25..05a76a71a4 100644
--- a/include/clang/Basic/DiagnosticSemaKinds.td
+++ b/include/clang/Basic/DiagnosticSemaKinds.td
@@ -1780,6 +1780,8 @@ def ext_forward_ref_enum : Extension<
   "ISO C forbids forward references to 'enum' types">;
 def err_forward_ref_enum : Error<
   "ISO C++ forbids forward references to 'enum' types">;
+def ext_ms_forward_ref_enum : Extension<
+  "forward references to 'enum' types are a Microsoft extension">, InGroup<Microsoft>;
 def ext_forward_ref_enum_def : Extension<
   "redeclaration of already-defined enum %0 is a GNU extension">, InGroup<GNU>;
   
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index e4dca2ba98..21b328d64c 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -5755,9 +5755,12 @@ CreateNewDecl:
           << New;
         Diag(Def->getLocation(), diag::note_previous_definition);
       } else {
-        Diag(Loc, 
-             getLangOptions().CPlusPlus? diag::err_forward_ref_enum
-                                       : diag::ext_forward_ref_enum);
+        unsigned DiagID = diag::ext_forward_ref_enum;
+        if (getLangOptions().Microsoft)
+          DiagID = diag::ext_ms_forward_ref_enum;
+        else if (getLangOptions().CPlusPlus)
+          DiagID = diag::err_forward_ref_enum;
+        Diag(Loc, DiagID);
       }
     }
   } else {
diff --git a/test/SemaCXX/MicrosoftExtensions.cpp b/test/SemaCXX/MicrosoftExtensions.cpp
index 93650a53f4..7cc1675f2e 100644
--- a/test/SemaCXX/MicrosoftExtensions.cpp
+++ b/test/SemaCXX/MicrosoftExtensions.cpp
@@ -84,3 +84,7 @@ void m1() {
   h1<int>(&M::addP);
   h1(&M::subtractP);
 } 
+
+//MSVC allows forward enum declaration
+enum ENUM; // expected-warning {{forward references to 'enum' types are a Microsoft extension}}
+ENUM *var;