Fix PR8720 by printing an error message with a substring that the gcc testsuite searches for.

llvm-svn: 121137

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -1001,6 +1001,8 @@ def err_attribute_weakref_not_global_context : Error<
   "weakref declaration of '%0' must be in a global context">;
 def err_attribute_weakref_without_alias : Error<
   "weakref declaration of '%0' must also have an alias attribute">;
+def err_alias_not_supported_on_darwin : Error <
+  "only weak aliases are supported on darwin">;
 def warn_attribute_wrong_decl_type : Warning<
   "%0 attribute only applies to %select{function|union|"
   "variable and function|function or method|parameter|"

clang/lib/Sema/SemaDeclAttr.cpp

@@ -675,6 +675,11 @@ static void HandleAliasAttr(Decl *d, const AttributeList &Attr, Sema &S) {
     return;
   }
 
+  if (S.Context.Target.getTriple().getOS() == llvm::Triple::Darwin) {
+    S.Diag(Attr.getLoc(), diag::err_alias_not_supported_on_darwin);
+    return;
+  }
+
   // FIXME: check if target symbol exists in current file
 
   d->addAttr(::new (S.Context) AliasAttr(Attr.getLoc(), S.Context,

clang/test/CodeGen/2008-07-29-override-alias-decl.c

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -emit-llvm -o - %s | FileCheck %s
 
 int x() { return 1; }
 

clang/test/CodeGen/pragma-weak.c

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -emit-llvm %s -o - -verify | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -emit-llvm %s -o - -verify | FileCheck %s
 
 // CHECK: @weakvar = weak global
 // CHECK: @__weakvar_alias = common global

clang/test/CodeGenCXX/attr.cpp

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -triple x86_64-apple-darwin -emit-llvm -o - %s | FileCheck %s
+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -emit-llvm -o - %s | FileCheck %s
 
 // CHECK: @test2 = alias i32 ()* @_Z5test1v
 

clang/test/Sema/attr-alias.c

@@ -0,0 +1,8 @@
+// RUN: %clang_cc1 -triple x86_64-apple-darwin  -fsyntax-only -verify %s
+
+void g() {}
+
+// It is important that the following string be in the error message. The gcc
+// testsuite looks for it to decide if a target supports aliases.
+
+void f() __attribute__((alias("g"))); //expected-error {{only weak aliases are supported}}

clang/test/SemaCXX/attr-weakref.cpp

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -fsyntax-only -verify %s
+// RUN: %clang_cc1 -triple x86_64-pc-linux-gnu -fsyntax-only -verify %s
 
 // GCC will accept anything as the argument of weakref. Should we
 // check for an existing decl?