Re: gcc optimization changes results

nirnimesh wrote:

gcc optimizaton (with -O1 or -O2) is producing unexpected and wrong
results for my program. I get correct answers with no optimizations.
I'm using gcc 4.0 on FC4-x86_64. I replaced -O1 with the options it
enabls (from gcc manpage) but that doesn't trace the problem. How
should I approach to solve this problem? What should I be checking?

Not to rain on your parade, but a bug in GCC is less likely than a bug
in your application.

Your problem sounds like undefined behavior somewhere in your program.
.

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