1 /* Verify that calls to fprintf don't get eliminated even if their
2 result on success can be computed at compile time (they can fail).
3 The calls can still be transformed into those of other functions.
4 { dg-skip-if "requires io" { freestanding } } */
5
6 #include <stdio.h>
7 #include <stdlib.h>
8 #include <string.h>
9
main(void)10 int main (void)
11 {
12 char *tmpfname = tmpnam (0);
13 FILE *f = fopen (tmpfname, "w");
14 if (!f)
15 {
16 perror ("fopen for writing");
17 return 1;
18 }
19
20 fprintf (f, "1");
21 fprintf (f, "%c", '2');
22 fprintf (f, "%c%c", '3', '4');
23 fprintf (f, "%s", "5");
24 fprintf (f, "%s%s", "6", "7");
25 fprintf (f, "%i", 8);
26 fprintf (f, "%.1s\n", "9x");
27 fclose (f);
28
29 f = fopen (tmpfname, "r");
30 if (!f)
31 {
32 perror ("fopen for reading");
33 remove (tmpfname);
34 return 1;
35 }
36
37 char buf[12] = "";
38 if (1 != fscanf (f, "%s", buf))
39 {
40 perror ("fscanf");
41 fclose (f);
42 remove (tmpfname);
43 return 1;
44 }
45
46 fclose (f);
47 remove (tmpfname);
48
49 if (strcmp (buf, "123456789"))
50 abort ();
51
52 return 0;
53 }
54