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From: Simon Marchi <simon.marchi@polymtl.ca>
To: vijay nag <vijunag@gmail.com>
Cc: gdb@sourceware.org
Subject: Re: amd64 executable debugging
Date: Sat, 24 Mar 2018 17:03:00 -0000	[thread overview]
Message-ID: <d3802e89a10ea2e1bb56a61b9de28712@polymtl.ca> (raw)
In-Reply-To: <CAKhyrx8vBjMg+140b8XWLnw92-J1oh206sO6UOtR7X7BCnDL+w@mail.gmail.com>

On 2018-03-24 09:14, vijay nag wrote:
> Hello GDB,
> 
> Most often while debugging amd64 executable, GDB throws '<variable
> optimized out>' error and also sometimes when function parameters are
> passed on register GDB reports incorrect information in few frames. I'm
> sure in 64 bit with more registers available, there is more revenue for
> optimization, it is entirely possible that GDB gets confused due to 
> that
> and information provided by GDB isn't reliable sometimes.  I'm 
> wondering if
> the latest GDB has somehow solved this problem Or disassembling and
> studying instructions is the only way to go about it ? Also, is there a 
> way
> to increase this debug-ability by adding any additional compiler flags 
> ?
> 
> --Vijay--

Hi Vijay,

You didn't mention it so I'll state the obvious, do you build without 
optimizations (-O0)?  Otherwise, it's expected to have some optimized 
out values.

Simon


  reply	other threads:[~2018-03-24 17:03 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
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     [not found]                             ` <CAKhyrx9Y7GSN0PrUBYsPi63ngQKkpsyNbMf5+x6TBpinqF=D2Q@mail.gmail.com>
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     [not found]                                   ` <CAKhyrx9t6VGEe5Zc-KwO3Cp-KLV+JUqtCnbQaUK7qcQqToz2aA@mail.gmail.com>
2018-03-24 13:14                                     ` vijay nag
2018-03-24 17:03                                       ` Simon Marchi [this message]
2018-03-25  6:02                                         ` vijay nag
2018-03-25  6:04                                           ` vijay nag
2018-03-25 11:35                                             ` Simon Marchi

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