1 struct
2 {
3 int input;
4 int output;
5 }
6 ffstesttab[] =
7 {
8 #if __INT_MAX__ >= 2147483647
9 /* at least 32-bit integers */
10 { 0x80000000, 32 },
11 { 0xa5a5a5a5, 1 },
12 { 0x5a5a5a5a, 2 },
13 { 0xcafe0000, 18 },
14 #endif
15 #if __INT_MAX__ >= 32767
16 /* at least 16-bit integers */
17 { 0x8000, 16 },
18 { 0xa5a5, 1 },
19 { 0x5a5a, 2 },
20 { 0x0ca0, 6 },
21 #endif
22 #if __INT_MAX__ < 32767
23 #error integers are too small
24 #endif
25 };
26
27 #define NFFSTESTS (sizeof (ffstesttab) / sizeof (ffstesttab[0]))
28
29 extern void abort (void);
30 extern void exit (int);
31
32 int
main(void)33 main (void)
34 {
35 int i;
36
37 for (i = 0; i < NFFSTESTS; i++)
38 {
39 if (__builtin_ffs (ffstesttab[i].input) != ffstesttab[i].output)
40 abort ();
41 }
42
43 exit (0);
44 }
45