blob: 30e07a60ea4a0d526fe96648227463db1d94492c (
plain)
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
36
37
38
39
40
41
42
43
44
45
|
/* NOCW */
/* dggccbug.c */
/* bug found by Eric Young (eay@cryptsoft.com) - May 1995 */
#include <stdio.h>
/* There is a bug in
* gcc version 2.5.8 (88open OCS/BCS, DG-2.5.8.3, Oct 14 1994)
* as shipped with DGUX 5.4R3.10 that can be bypassed by defining
* DG_GCC_BUG in my code.
* The bug manifests itself by the vaule of a pointer that is
* used only by reference, not having it's value change when it is used
* to check for exiting the loop. Probably caused by there being 2
* copies of the valiable, one in a register and one being an address
* that is passed. */
/* compare the out put from
* gcc dggccbug.c; ./a.out
* and
* gcc -O dggccbug.c; ./a.out
* compile with -DFIXBUG to remove the bug when optimising.
*/
void inc(a)
int *a;
{
(*a)++;
}
main()
{
int p=0;
#ifdef FIXBUG
int dummy;
#endif
while (p<3)
{
fprintf(stderr,"%08X\n",p);
inc(&p);
#ifdef FIXBUG
dummy+=p;
#endif
}
}
|
