projects / thirdparty / openssl.git / blame
| Commit | Line | Data |
|---|---|---|
| d02b48c6 RE |
1 | /* NOCW */ |
| 2 | /* dggccbug.c */ | |
| 3 | /* bug found by Eric Young (eay@cryptsoft.com) - May 1995 */ | |
| 4 | ||
| 5 | #include <stdio.h> | |
| 6 | ||
| 7 | /* There is a bug in | |
| 8 | * gcc version 2.5.8 (88open OCS/BCS, DG-2.5.8.3, Oct 14 1994) | |
| 9 | * as shipped with DGUX 5.4R3.10 that can be bypassed by defining | |
| 10 | * DG_GCC_BUG in my code. | |
| 11 | * The bug manifests itself by the vaule of a pointer that is | |
| 12 | * used only by reference, not having it's value change when it is used | |
| 13 | * to check for exiting the loop. Probably caused by there being 2 | |
| 14 | * copies of the valiable, one in a register and one being an address | |
| 15 | * that is passed. */ | |
| 16 | ||
| 17 | /* compare the out put from | |
| 18 | * gcc dggccbug.c; ./a.out | |
| 19 | * and | |
| 20 | * gcc -O dggccbug.c; ./a.out | |
| 21 | * compile with -DFIXBUG to remove the bug when optimising. | |
| 22 | */ | |
| 23 | ||
| 24 | void inc(a) | |
| 25 | int *a; | |
| 26 | { | |
| 27 | (*a)++; | |
| 28 | } | |
| 29 | ||
| 30 | main() | |
| 31 | { | |
| 32 | int p=0; | |
| 33 | #ifdef FIXBUG | |
| 34 | int dummy; | |
| 35 | #endif | |
| 36 | ||
| 37 | while (p<3) | |
| 38 | { | |
| 39 | fprintf(stderr,"%08X\n",p); | |
| 40 | inc(&p); | |
| 41 | #ifdef FIXBUG | |
| 42 | dummy+=p; | |
| 43 | #endif | |
| 44 | } | |
| 45 | } |