fix cgen_test

vlib/compiler/cc.v

@@ -439,6 +439,7 @@ fn (c mut V) cc_windows_cross() {
 	include := '-I $winroot/include '
 	*/
 	mut cmd := ''
+	cmd = ''
 	$if macos {
 		cmd = 'x86_64-w64-mingw32-gcc $args -municode'
 	}

vlib/v/gen/tests/1.c

@@ -33,6 +33,8 @@ void myuser() {
 	User user = (User){
 		.age = 10,
 	};
-	User age = user.age;
+	int age = user.age + 1;
+	int boo = 2;
+	int boo2 = boo + 1;
 	bool b = age > 0;
 }