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