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From: Emmet Ford <emmet@optonline.net>
To: linux-assembly@vger.kernel.org
Subject: Re: gdb help
Date: Mon, 23 Feb 2004 20:18:28 -0500	[thread overview]
Message-ID: <403AA664.1070501@optonline.net> (raw)

I use gas rather than nasm, but I also find that I am unable to break on 
the first instruction in a program. Generally, what I do is use the gdb 
'list' command to list out the program and then set a break point on the 
line number of the second instruction in the program.

This issue is documented in various places, one of them being 
http://www.csee.umbc.edu/~chang/cs313.f03/gdb_help.shtml, where it says:

-->
Due to a bug in gdb,

<br> break *_start<br> does not stop the program before the execution of 
the first instruction. A workaround is to add a no operation instruction 
(mnemonic "nop") to the beginning of your program and use: <br> break 
*_start+1

<--

This may not be the problem that you are experiencing, however, since 
programs normally start at _start, not main. In any case, you might try 
break *main+1

--Emmet Ford



             reply	other threads:[~2004-02-24  1:18 UTC|newest]

Thread overview: 2+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2004-02-24  1:18 Emmet Ford [this message]
  -- strict thread matches above, loose matches on Subject: below --
2004-02-21 17:36 gdb help glburt

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