Re: Segfault in _Unwind_* code called from pthread_exit

On 31.10.17 22:36, Gerald Pfeifer wrote:
> On Tue, 31 Oct 2017, Andreas Tobler wrote:
>> Do we, FreeBSD'ers, want to have gcc unwind support on older than
>> FreeBSD 9.3 releases? I think the gcc folks do not care, but we are the
>> ones who might have an need for such a support?
>> _at_Gerald, do you have an opinion?
> 
> Yes. No. :-)
> 
> Those possibly still stuck on obsolete versions of FreeBSD don't
> need/want fancy new compilers and GCC 4.9 is still available for
> use and does not exhibit this issue, correct?  (If it does, nobody
> reported any problems.)

It is limited to gcc >=5, gcc-4.9 does not have the 
MD_FALLBACK_FRAME_STATE_FOR defined.

>> I can 'ifdef' the new code and in the 'else' case we fall back to
>> the already existing path.
> 
> If it's "cheap", that might be nice.

Attached, the test is running on gcc trunk and gcc-6. gcc-6 is the last 
one with java support and there we have quite extensive test cases which 
really test for this MD_FALLBACK_FRAME_STATE_FOR macro. These test 
cases, Throw_2 and co do pass. So I think the new bits should be fine.
Also some coming asan test cases do pass with this addition too.

> Thanks to the three of you - Tijl, Konstantin, and Andreas!

Gruss,
Andreas