test: add sample targets

Author: liblaf

targets/struct.c

@@ -0,0 +1,13 @@
+struct RT {
+  char A;
+  int B[10][20];
+  char C;
+};
+
+struct ST {
+  int X;
+  double Y;
+  struct RT Z;
+};
+
+int *foo(struct ST *s) { return &s[1].Z.B[5][13]; }