File: strncpy-2.c

package info (click to toggle)
gcc-riscv64-unknown-elf 8.3.0.2019.08%2Bdfsg-1
  • links: PTS, VCS
  • area: main
  • in suites: bullseye
  • size: 680,956 kB
  • sloc: ansic: 3,237,715; cpp: 896,882; ada: 772,854; f90: 144,254; asm: 68,788; makefile: 67,456; sh: 29,743; exp: 28,045; objc: 15,273; fortran: 11,885; python: 7,369; pascal: 5,375; awk: 3,725; perl: 2,872; yacc: 316; xml: 311; ml: 285; lex: 198; haskell: 122
file content (35 lines) | stat: -rw-r--r-- 914 bytes parent folder | download | duplicates (2) 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
 
/* PR tree-optimization/83075 - Invalid strncpy optimization */
/* { dg-do run } */
/* { dg-options "-O2 -Wstringop-overflow" } */

typedef __SIZE_TYPE__ size_t;

__attribute__((noipa)) size_t
foo (char *p, char *q, size_t *r)
{
  size_t n0 = __builtin_strlen (p);
  __builtin_strncpy (q, p, n0);		/* { dg-warning "specified bound depends on the length" } */
  size_t n1 = __builtin_strlen (p);
  *r = n0;
  return n1;
}

int
main ()
{
  char a[8] = "";
  __builtin_strcpy (a, "123");
  size_t n0 = __builtin_strlen (a);
  __builtin_strncpy (a + 3, a, n0);	/* { dg-warning "specified bound depends on the length" } */
  size_t n1 = __builtin_strlen (a);
  if (n1 == n0)
    __builtin_abort ();
  a[6] = '7';
  __builtin_strcpy (a, "456");
  size_t n2;
  if (foo (a, a + 3, &n2) != 7 || n2 != 3)
    __builtin_abort ();
  if (__builtin_memcmp (a, "4564567", sizeof "4564567"))
    __builtin_abort ();
  return 0;
}