Testing inlining with gcc 4.0.4:

test.c:

#include <stdio.h>

inline void test(int a) {
        printf("%d\n", a);
}

int main(void) {
        void (*fnc)(int);

        test(1);

        fnc = &test;
        (*fnc)(2);

        return 0;
}

Compiling: gcc -O test.c

Disasm:

08048360 <test>:
 8048360:       55                      push   %ebp
 8048361:       89 e5                   mov    %esp,%ebp
 8048363:       83 ec 08                sub    $0x8,%esp
 8048366:       8b 45 08                mov    0x8(%ebp),%eax
 8048369:       89 44 24 04             mov    %eax,0x4(%esp)
 804836d:       c7 04 24 a0 84 04 08    movl   $0x80484a0,(%esp)
 8048374:       e8 37 ff ff ff          call   80482b0 <printf@plt>
 8048379:       c9                      leave
 804837a:       c3                      ret

0804837b <main>:
 804837b:       55                      push   %ebp
 804837c:       89 e5                   mov    %esp,%ebp
 804837e:       83 ec 08                sub    $0x8,%esp
 8048381:       83 e4 f0                and    $0xfffffff0,%esp
 8048384:       83 ec 10                sub    $0x10,%esp
 8048387:       c7 44 24 04 01 00 00    movl   $0x1,0x4(%esp)
 804838e:       00
 804838f:       c7 04 24 a0 84 04 08    movl   $0x80484a0,(%esp)
 8048396:       e8 15 ff ff ff          call   80482b0 <printf@plt>
 804839b:       c7 04 24 02 00 00 00    movl   $0x2,(%esp)
 80483a2:       e8 b9 ff ff ff          call   8048360 <test>
 80483a7:       b8 00 00 00 00          mov    $0x0,%eax
 80483ac:       c9                      leave
 80483ad:       c3                      ret
 80483ae:       90                      nop
 80483af:       90                      nop