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From: Joel Brobecker <brobecker@adacore.com>
To: fei ding <fdingiit@gmail.com>
Cc: gdb@sourceware.org
Subject: Re: How does GDB know the architecture of an executable?
Date: Fri, 16 Jan 2015 06:56:00 -0000	[thread overview]
Message-ID: <20150116065646.GH28195@adacore.com> (raw)
In-Reply-To: <CAGmPkfLEjBCy_A4z0AS5hFkwySDDKwGP6JsaVk2usARSD8sJPw@mail.gmail.com>

> I'm wondering how does GDB know the architecture of an executable, for
> example, if I use -m32 options in gcc and I can get an i386
> executable, if I use nothing I'll get a x86-64 executable while I am
> compiling code on a 64-bit Linux.
> 
> I've see the source code for one day but I cannot get what I want, at
> first I think '''struct gdbarch''' has something with it. Can anyone
> help me? I want to know everything about this.

There are a number of elements GDB uses to determine the exact
"arch" to use. A lot of it relies on the "bfd" library, which
is part of binutils, to tell us. On GNU/Linux, I'd take a look
at the ELF documentation.

-- 
Joel


      reply	other threads:[~2015-01-16  6:56 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2015-01-16  3:48 fei ding
2015-01-16  6:56 ` Joel Brobecker [this message]

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