Messages in this thread | | | Date | Thu, 19 Nov 1998 17:10:04 -0800 | From | Steven Roberts <> | Subject | Re: have a look at this proggie, please. |
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David Weinehall wrote: > That's NOT an divide by zero... > > Output: > > -2147483648 * -1 = -2147483648 > Floating exception > ^^^^^^^^^^^^^^^^^^ > > Quite obviously, -MAXINT-1 * -1 is too large for an integer to hold (by > one), but it should *NOT* report a floating exception... Right?!
Not sure if this is Intelish behavior or POSIX, but divide by zero and overflow are treated as SIGFPE's (FPE_INTOVFLOW and FPE_INTDIV0)
I just looked at this a bit back under borland (I do a lot of my work with Borland still -- still working on convincing management to at least try out linux). It looked like though it was the way the processor reports them (from my 386/486 processor book -- can't check right now, book got borrowed). (I had to patch Borland's RTL to allow me to step over the offending instruction so I could ignore the behavior -- kind of fun manually decoding DIV and IDIV in C code :)
So assuming that they are looped under FPE, then the behavior is correct. the main signal is the SIGFPE, the sub action is FPE_INTOVLOW.
Regards, Steven Roberts
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