Re: feature tests for pthreads implementation and configuration?

Hello Mikael,


Actually I failed to consider that I ran FC3 with kernel 2.6.16 and
FC4 with an earlier RH 2.6 kernel. It turns out that the issue
comes from the 2.6.16 kernel, not FC3-vs-FC4 pthreads. (And I did
get NPTL with FC3; I looked at the wrong place and found the fallback
LinuxThreads code instead of the NPTL code it actually used.)

The issue is that kernel 2.6.16 clears a new thread's sigaltstack
settings (as per SUSv3) while previous kernels and apparently also
Solaris 9/x86 preserved it. That caused SIGFPEs in our threads to
be delivered on the current stack (a big no-no in our runtime system)
instead of the alt stack, causing memory corruption and SIGSEGVs.

The simple solution was to have each thread allocate and install
its own alt stack before starting running application code.

Thanks for the info.

It is always nice when the poster solves its own problem ;-)

Cheers,
Loic.

.

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