[cfe-commits] r160681 - in /cfe/trunk: include/clang/Basic/DiagnosticSemaKinds.td lib/Sema/SemaDecl.cpp test/SemaCXX/function-extern-c.cpp

[Hans Wennborg]

Author: hans
Date: Tue Jul 24 12:59:41 2012
New Revision: 160681

URL: http://llvm.org/viewvc/llvm-project?rev=160681&view=rev
Log:
Tweak warning text for returning incomplete type from extern "C" functions.

A warning was added in r150128 for returning non-C compatible
user-defined types from functions with C linkage.

This makes the text more clear for the case when the type isn't
decidedly non-C compatible, but incomplete.

Modified:
    cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
    cfe/trunk/lib/Sema/SemaDecl.cpp
    cfe/trunk/test/SemaCXX/function-extern-c.cpp

Modified: cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td?rev=160681&r1=160680&r2=160681&view=diff
==============================================================================
--- cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td (original)
+++ cfe/trunk/include/clang/Basic/DiagnosticSemaKinds.td Tue Jul 24 12:59:41 2012
@@ -192,6 +192,9 @@
 def warn_return_value_udt: Warning<
   "%0 has C-linkage specified, but returns user-defined type %1 which is "
   "incompatible with C">, InGroup<ReturnTypeCLinkage>;
+def warn_return_value_udt_incomplete: Warning<
+  "%0 has C-linkage specified, but returns incomplete type %1 which could be "
+  "incompatible with C">, InGroup<ReturnTypeCLinkage>;
 def warn_implicit_function_decl : Warning<
   "implicit declaration of function %0">,
   InGroup<ImplicitFunctionDeclare>, DefaultIgnore;

Modified: cfe/trunk/lib/Sema/SemaDecl.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Sema/SemaDecl.cpp?rev=160681&r1=160680&r2=160681&view=diff
==============================================================================
--- cfe/trunk/lib/Sema/SemaDecl.cpp (original)
+++ cfe/trunk/lib/Sema/SemaDecl.cpp Tue Jul 24 12:59:41 2012
@@ -6086,10 +6086,11 @@
     // compatible, and if it does, warn the user.
     if (NewFD->isExternC()) {
       QualType R = NewFD->getResultType();
-      if (!R.isPODType(Context) && 
-          !R->isVoidType())
-        Diag( NewFD->getLocation(), diag::warn_return_value_udt ) 
-          << NewFD << R;
+      if (R->isIncompleteType() && !R->isVoidType())
+        Diag(NewFD->getLocation(), diag::warn_return_value_udt_incomplete)
+            << NewFD << R;
+      else if (!R.isPODType(Context) && !R->isVoidType())
+        Diag(NewFD->getLocation(), diag::warn_return_value_udt) << NewFD << R;
     }
   }
   return Redeclaration;

Modified: cfe/trunk/test/SemaCXX/function-extern-c.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/function-extern-c.cpp?rev=160681&r1=160680&r2=160681&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/function-extern-c.cpp (original)
+++ cfe/trunk/test/SemaCXX/function-extern-c.cpp Tue Jul 24 12:59:41 2012
@@ -36,3 +36,5 @@
 extern "C" double f8(void);
 extern "C" long long f11( void );
 extern "C" A *f10( void );
+
+extern "C" struct mypodstruct f12(); // expected-warning {{'f12' has C-linkage specified, but returns incomplete type 'struct mypodstruct' which could be incompatible with C}}