Walk the decls looking for the last one that has an attribute. We do have to walk

them, otherwise we cannot produce an error for both

struct HIDDEN test4; // canonical
struct test4;
struct DEFAULT test4;

and

struct test5; // canonical
struct HIDDEN test5;
struct DEFAULT test5;

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@156016 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Sema/SemaDeclAttr.cpp

@@ -1757,13 +1757,16 @@ static void handleVisibilityAttr(Sema &S, Decl *D, const AttributeList &Attr) {
     return;
   }
 
-  Decl *PrevDecl;
-  if (isa<FunctionDecl>(D))
-    PrevDecl = D->getMostRecentDecl()->getPreviousDecl();
-  else
-    PrevDecl = D->getCanonicalDecl();
+  // Find the last Decl that has an attribute.
+  VisibilityAttr *PrevAttr;
+  assert(D->redecls_begin() == D);
+  for (Decl::redecl_iterator I = D->redecls_begin(), E = D->redecls_end();
+       I != E; ++I) {
+    PrevAttr = I->getAttr<VisibilityAttr>() ;
+    if (PrevAttr)
+      break;
+  }
 
-  VisibilityAttr *PrevAttr = PrevDecl ? PrevDecl->getAttr<VisibilityAttr>() : 0;
   if (PrevAttr) {
     VisibilityAttr::VisibilityType PrevVisibility = PrevAttr->getVisibility();
     if (PrevVisibility != type) {

test/Sema/attr-visibility.c

@@ -10,3 +10,7 @@ void test3() __attribute__((visibility("protected"))); // expected-warning {{tar
 struct __attribute__((visibility("hidden"))) test4; // expected-note {{previous attribute is here}}
 struct test4;
 struct __attribute__((visibility("default"))) test4; // expected-error {{visibility does not match previous declaration}}
+
+struct test5;
+struct __attribute__((visibility("hidden"))) test5; // expected-note {{previous attribute is here}}
+struct __attribute__((visibility("default"))) test5; // expected-error {{visibility does not match previous declaration}}