Fix crash when LHS of pointer arithmetic is not ElementRegion.


git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@66649 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/test/Analysis/ptr-arith.c b/test/Analysis/ptr-arith.c
index a8d03eb..7b66b2f 100644
--- a/test/Analysis/ptr-arith.c
+++ b/test/Analysis/ptr-arith.c
@@ -5,3 +5,10 @@
   int *p = a;
   ++p;
 }
+
+char* foo();
+
+void f2() {
+  char *p = foo();
+  ++p;
+}