make some objc redefinition warnings more consistent: call definitions 
"definitions", not declarations.  Point out the location of the 
original definition.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@59919 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Sema/SemaDeclObjC.cpp b/lib/Sema/SemaDeclObjC.cpp
index 7ffae47..c030a37 100644
--- a/lib/Sema/SemaDeclObjC.cpp
+++ b/lib/Sema/SemaDeclObjC.cpp
@@ -76,6 +76,8 @@
     // Class already seen. Is it a forward declaration?
     if (!IDecl->isForwardDecl()) {
       Diag(AtInterfaceLoc, diag::err_duplicate_class_def) << IDecl->getName();
+      Diag(IDecl->getLocation(), diag::note_previous_definition);
+
       // Return the previous class interface.
       // FIXME: don't leak the objects passed in!
       return IDecl;
@@ -188,6 +190,7 @@
     // Protocol already seen. Better be a forward protocol declaration
     if (!PDecl->isForwardDecl()) {
       Diag(ProtocolLoc, diag::err_duplicate_protocol_def) << ProtocolName;
+      Diag(PDecl->getLocation(), diag::note_previous_definition);
       // Just return the protocol we already had.
       // FIXME: don't leak the objects passed in!
       return PDecl;