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Date: Tue, 28 Dec 2010 23:02:00 -0000
From: Michael Snyder <msnyder@vmware.com>
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To: Jan Kratochvil <jan.kratochvil@redhat.com>
CC: Joel Brobecker <brobecker@adacore.com>,  Edjunior Barbosa Machado <emachado@linux.vnet.ibm.com>, "gdb@sourceware.org" <gdb@sourceware.org>
Subject: Re: next/step after main() function's return
References: <4D19144E.1030504@linux.vnet.ibm.com> <20101228052055.GY2618@adacore.com> <20101228082324.GA29391@host0.dyn.jankratochvil.net>
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Jan Kratochvil wrote:
> On Tue, 28 Dec 2010 06:20:55 +0100, Joel Brobecker wrote:
>>> when issuing a next or step after main() function's return statement,
>>> gdb drops to __libc_start_main() from libc on x86 (or
>>> generic_start_main() on ppc and so on, depending on the arch if I'm
>>> not mistaken). Is it considered a bug or it's just the expected
>>> behavior?
>> I'd say that this is expected behavior. `main' is called by
>> __libc_start_main, so "next"-ing out of main will land in that function.
> 
> With default `set backtrace past-main off' the user may expect it to behave
> differently.  Still the atexit functions could be "next"ed so GDB would have
> to identify somehow their calls.

I'm guessing this happens because libc_start_main is compiled with -g.

Otherwise, gdb would continue executing "in the woods" until exit.