A global without initializer must be emitted as weak.
Fix Olden/bh test.

llvm-svn: 47292
diff --git a/clang/test/CodeGen/weak-global.c b/clang/test/CodeGen/weak-global.c
new file mode 100644
index 0000000..86e551c
--- /dev/null
+++ b/clang/test/CodeGen/weak-global.c
@@ -0,0 +1,3 @@
+// RUN: clang -emit-llvm < %s | grep weak
+
+int i;