Make sure weak symbols are listed after the local ones.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115795 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/MC/MCELFStreamer.cpp b/lib/MC/MCELFStreamer.cpp
index b63bedc..65a0a7d 100644
--- a/lib/MC/MCELFStreamer.cpp
+++ b/lib/MC/MCELFStreamer.cpp
@@ -272,6 +272,7 @@
   case MCSA_WeakReference:
   case MCSA_Weak:
     SetBinding(SD, ELF::STB_WEAK);
+    SD.setExternal(true);
     BindingExplicitlySet.insert(Symbol);
     break;