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To: Steve Teale <steve.teale@britseyeview.com>
Cc: gcc-help <gcc-help@gcc.gnu.org>
Subject: Re: Strange debug behavior with 4.4.3
References: <1267613238.12719.16.camel@Ubuntu> 	<mcrocj5l8g0.fsf@dhcp-172-17-9-151.mtv.corp.google.com> 	<1267631764.12719.27.camel@Ubuntu>
From: Ian Lance Taylor <iant@google.com>
Date: Wed, 03 Mar 2010 16:08:00 -0000
In-Reply-To: <1267631764.12719.27.camel@Ubuntu> (Steve Teale's message of "Wed\, 03 Mar 2010 18\:56\:04 +0300")
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Steve Teale <steve.teale@britseyeview.com> writes:

> On Wed, 2010-03-03 at 07:40 -0800, Ian Lance Taylor wrote:
>> Steve Teale <steve.teale@britseyeview.com> writes:
>> 
>> > (gdb) n
>> > 6313	    input_location = EXPR_LOCATION (*expr_p);
>> > (gdb) n
>> > 6729				   post_p == &internal_post ? NULL : post_p,
>> >
>> > Things go pear shaped after line 6312 - after that, next seems to get
>> > you somewhere rather arbitrary.
>> 
>> You are debugging optimized code.  Random jumps do happen.  You need
>> to go further to see if there is a real problem here.
>> 
>> Ian
>
> Ian,
>
> Go further?

I mean: run the "n" command a few more times to see where you get to.

> So should I build the compiler with no optimization?

That is probably a good idea if you want to debug the compiler.

Ian