add a silly testcase

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@59877 91177308-0d34-0410-b5e6-96231b3b80d8

test/Sema/exprs.c

@@ -33,3 +33,8 @@ void test6() {
   int X;
   X();  // expected-error {{called object type 'int' is not a function or function pointer}}
 }
+
+void test7(int *P, _Complex float Gamma) {
+   P = (P-42) + Gamma*4;  // expected-error {{invalid operands to binary expression ('int *' and '_Complex float')}}
+}
+