Re: libc recently more aggressive about pthread locks in stable ?
On Mon, Nov 14, 2016 at 10:31:18AM +0100, Gert Wollny wrote:
> Am Sonntag, den 06.11.2016, 01:12 -0200 schrieb Henrique de Moraes
> Holschuh:
> >
> >
> >
> > Unfortunately, when hardware lock elision support was added to glibc
> > upstream, libpthreads was *not* changed to properly assert() this
> > forbidden condition on the non-hardware-elision codepaths. Such an
> > assert() would have given us consistent behavior, thus flushing the
> > bugs out in the open... at the cost of a performance hit (I have no
> > idea how severe), and much screaming.
>
> An alternative to find problems with (un-)locking should be to compile
> the program in question with -fsanitize=thread (on amd64) and run it.
>
> Unfortunately, in current unstable with thread sanitizer one might get
> #796246 (at least I had this).
Does "-fsanitize=thread -no-pie" work for you?
> Best,
> Gert
cu
Adrian
--
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of the darkness. There had been need of rain for many days.
"Only a promise," Lao Er said.
Pearl S. Buck - Dragon Seed
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