Fix redundant errors for redefinitions with multiple existing definitions.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@64081 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDecl.cpp b/lib/Sema/SemaDecl.cpp
index cdb6930..f5681af 100644
--- a/lib/Sema/SemaDecl.cpp
+++ b/lib/Sema/SemaDecl.cpp
@@ -604,6 +604,8 @@
           VD->getStorageClass() != VarDecl::PrivateExtern) {
         Diag(VD->getLocation(), diag::err_redefinition) << VD->getDeclName();
         Diag(OldDecl->getLocation(), diag::note_previous_definition);
+        // One redefinition error is enough.
+        break;
       }
     }
   }
diff --git a/test/Sema/tentative-decls.c b/test/Sema/tentative-decls.c
index 6390d9c..0e4b13a 100644
--- a/test/Sema/tentative-decls.c
+++ b/test/Sema/tentative-decls.c
@@ -1,6 +1,4 @@
 // RUN: clang %s -verify -fsyntax-only
-// XFAIL
-// fails due to exact diagnostic matching
 
 const int a [1] = {1};
 extern const int a[];