When compiling the test with `gcc -std=c11 -fsyntax-only`
runnable/test22513.c:16:12: error: invalid use of undefined type ‘struct S’
16 | int* p = &s.t.x;
| ^
Original test:
```
struct S s;
int* p = &s.t.x;
struct S { int a; struct T t; };
```
Comment #1 by bugzilla — 2023-02-20T07:29:52Z
ImportC allows forward references as an extension.