Mitesh Thakkar <mail.mthakkar@xxxxxxxxx> writes: > On Fri, Jul 22, 2011 at 3:09 PM, Mitesh Thakkar <mail.mthakkar@xxxxxxxxx> wrote: >> Hi All, >> >> I have developed one custom application in C. >> It is running fine in CentOS 5.6 64-bit, but it is crashing in CentOS >> 5.6 32-bit. >> I am not finding any reason/conclusion for it. >> Can anyone help me for it. > > Interestingly, it is not crashing on 32-bit if I give -O0 (I mean do > not optimize). > What could be the reason. I assume you are compiling with the -m32 option to generate 32-bit code. You neglected to mention which version of gcc you are using. You neglected to mention what the crash looks like--e.g., is it a segmentation violation or an illegal instruction? While of course it could be anything at all, the most likely reason is that your program is invalid C, and that the 32-bit optimizers are changing it in a way that causes it to not behave as you expect. If the program works as you expect if you compile with -O2 -fno-strict-aliasing -fno-strict-overflow then that is almost certainly the problem. Ian
