From owner-freebsd-hackers@freebsd.org  Thu May  5 15:32:37 2016
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 for freebsd-hackers@freebsd.org; Thu, 05 May 2016 18:32:23 +0300
Subject: Re: corrupted stack (backtrace) from sigaction handler
To: freebsd-hackers@freebsd.org
References: <94c8456c-a9b4-77a5-6622-418fc59d61d7@mail.ru>
From: trafdev <trafdev@mail.ru>
Message-ID: <6e191ad8-eb6e-769a-9a5c-f2bbe899971a@mail.ru>
Date: Thu, 5 May 2016 08:32:19 -0700
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Looks like it's a bug of FreeBSD - wherever an error occurs, user will 
see only 4 mentioned rows on a stack (using backtrace from a sigaction 
handler).

In any Linux stack unwinds up to the place where error actually occurred.

More outputs appreciated before creating a bug for a FreeBSD kernel.

On 05/01/16 09:46, trafdev wrote:
> Hello!
>
> Could you launch attached code on your machine and respond with an
> output (and FreeBSD version).
>
> Here is mine (FreeBSD 10.2) output:
>
>     stack dump [0]  0x40d4e5 <_Z9stackdumpPKc+0x85> at
> /ara/devel/sandbox/new/cpp/Release/cpp
>     stack dump [1]  0x40dafd <_Z13signalHandleriP9__siginfoPv+0x3d> at
> /ara/devel/sandbox/new/cpp/Release/cpp
>     stack dump [2]  0x801f30997 <pthread_sigmask+0x497> at /lib/libthr.so.3
>     stack dump [3]  0x801f301a8 <pthread_getspecific+0xdd8> at
> /lib/libthr.so.3
>
> All info before signalHandler (foo/foo2 functions) is missed.