David Mathog wrote:
Since the same code runs differently on two different Opteron models
it's probably either a memory access issue or the use of a compiler
flag that enables some feature on one model that is not present
on the other. For instance, SSE3 vs. SSE2, although I don't know
enough about these models to tell you what the most likely flag would
be. (The fact that it runs ok on the newer one and blows up on the
older one is consistent with this type of error.)
Assuming gcc, recompile with:
-O0 -g -std=c99 -Wall
and clean up any warnings that result until you get a clean build.
Repeat with -O3 and -O2, as for strange reasons that sometimes uncovers
logic problems not seen at -O0. Then run the resulting binary
within valgrind. Fix any memory access violations which are found.
Valgrind can also alert you to the use of unsupported operations.
The code compiles quite cleanly, but I am seeing different behavior with
different compiler flags and different compilers. We'll see if I can
bisect the problem into a small enough box.
Thanks for the poke in that direction...
--
Orion Poplawski
Technical Manager 303-415-9701 x222
NWRA/CoRA Division FAX: 303-415-9702
3380 Mitchell Lane [EMAIL PROTECTED]
Boulder, CO 80301 http://www.cora.nwra.com
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