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Date: Tue, 18 Dec 2007 13:29:00 -0000
From: Robert Dewar <dewar@adacore.com>
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To: Alexandre Oliva <aoliva@redhat.com>
CC: Joe Buck <Joe.Buck@synopsys.COM>, Geert Bosch <bosch@adacore.com>,   Daniel Berlin <dberlin@dberlin.org>,  Diego Novillo <dnovillo@google.com>,   Mark Mitchell <mark@codesourcery.com>,  Ian Lance Taylor <iant@google.com>,   Richard Guenther <richard.guenther@gmail.com>,  gcc-patches@gcc.gnu.org, gcc@gcc.gnu.org
Subject: Re: Designs for better debug info in GCC
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Alexandre Oliva wrote:
> On Dec 18, 2007, Robert Dewar <dewar@adacore.com> wrote:

>> OK, so you are agreeing that good debuggability is impossible
>> with all the optimizations in place, so once again, let's have
>> an optimziation level that optimizes as far as possible without
>> harming debuggability.
> 
> I don't oppose such an optimization level, even though I don't know
> that we agree on what "good debuggability" stands for.

My definition is that it should be indistinguishable from -O0
except that I could live without being able to modify variables.
> 
> It's just that changing optimizations is precisely *against* the goals
> of my current project.  So, don't expect significant efforts to this
> end from me at this time.

But you can't achieve the above criterion with your approach.