Messages in this thread | | | From | "Johan Kullstam" <> | Subject | Re: Preventing gcc from aligning stack??? | Date | 27 Jan 2000 18:00:28 -0500 |
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Horst von Brand <vonbrand@sleipnir.valparaiso.cl> writes:
> My question in this vein would be the -fno-strength-reduce. The gcc bug > that placed this in the kernel was in gcc-2.7.2, and was worked around in > 2.7.2.3 by just making this option unconditional. Both 2.2.15pre4 and > 2.3.41pre2 at least demand gcc-2.7.2.3 as minimal version.
just when you thought it was safe to go into the water...
strength-reduction is broken again in gcc-2.95.2 (aka the current release). i'm not sure about what versions actually do work.
for fun, try this one out. cut and paste the program bug.c.
$ gcc -O2 bug.c -o b0 $ gcc -O2 -fno-strength-reduce bug.c -o b1
run b1. notice it finish immediately. now run b0. notice how b0 never terminates (until you ^C it).
-- bug.c ----------------------------------------- static void bug(int size, int tries) { int i; int num = 0;
while (num < size) { for (i = 1; i < tries; i++) num++; } }
int main() { bug(5, 10); return 0; } -- bug.c -----------------------------------------
-- J o h a n K u l l s t a m [kullstam@ne.mediaone.net] Don't Fear the Penguin!
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