extern void f(void);
extern inline __attribute__((always_inline)) void g()
{
        f();
}

extern inline __attribute__((always_inline)) void g();
void v(void)
{
        g();
}

./extinline4.cil.c: In function ‘v’:
./extinline4.cil.c:5:59: error: inlining failed in call to ‘always_inline’ ‘g’: function body not available
    5 | __inline extern void ( __attribute__((__always_inline__)) g)(void) ;
      |                                                           ^
./extinline4.cil.c:13:3: note: called from here
   13 |   g();
      |   ^~~