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benchmark: initialize maxerr in cholesky.c - #6182
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maxerr is read before it is written in the verification loop
(if (maxerr < err) maxerr = err), which is undefined behavior.
Depending on the stale stack value this can trigger a spurious
"Hmm, probably it has bug." abort - e.g. on LoongArch with
gcc 14.2 it did so at M=1 even though the result was correct.
Fix it the same way benchmark/linpack.c already does
("maxerr = 0.;" before its check loop).
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Right, thank you |
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maxerr is read before it is written in the verification loop (if (maxerr < err) maxerr = err), which is undefined behavior. Depending on the stale stack value this can trigger a spurious "Hmm, probably it has bug." abort - e.g. on LoongArch with gcc 14.2 it did so at M=1 even though the result was correct.
Fix it the same way benchmark/linpack.c already does ("maxerr = 0.;" before its check loop).