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Date: Sat, 13 Jun 2009 18:18:00 -0000
Message-ID: <84fc9c000906131118q71f48e0atafdbf4288fa6a01d@mail.gmail.com>
Subject: Re: VTA guality assessment: better than -O0 ;-)
From: Richard Guenther <richard.guenther@gmail.com>
To: Eric Botcazou <ebotcazou@adacore.com>
Cc: gcc@gcc.gnu.org, Alexandre Oliva <aoliva@redhat.com>
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On Sat, Jun 13, 2009 at 8:00 PM, Eric Botcazou<ebotcazou@adacore.com> wrote:
>> Yes, I don't like -O0 producing worse debug info - what does
>> the -O0 -fvar-tracking-assignments results look like?
>
> I'd do the opposite: totally disable VTA at -O0 like we do for -fvar-trac=
king.
> We once tried to enable -fvar-tracking with -O0 at AdaCore and ended up w=
ith
> bloated and inferior debug info. =A0I think we shouldn't need to do anyth=
ing
> at -O0 apart from sufficiently curbing the code generator to get correct
> naive debug info; the sophisticated stuff should be reserved to -O and ab=
ove.

Well, I see FAILs for -O0 compared to -O1 with VTA - that doesn't look "rig=
ht".
How we fix this is not relevant - but we should try to do so.

Richard.