Date: Wed, 11 Feb 1998 18:41:05 -0800 (PST)
Message-Id: <199802120241.SAA17212@adit.ap.net>
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To: Eli Zaretskii <eliz AT is DOT elta DOT co DOT il>
From: Nate Eldredge <eldredge AT ap DOT net>
Subject: Re: src/gcc.opt in alpha 980101
Cc: andrewc AT rosemail DOT rose DOT hp DOT com, djgpp-workers AT delorie DOT com
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At 12:08  2/11/1998 +0200, Eli Zaretskii wrote:
>
>On Tue, 10 Feb 1998, Nate Eldredge wrote:
>
>> AFAIK, 2.7.2.1 does actually fix it. `-fstrength-reduce' is definitely
>> enabled for 2.7.2.1. I looked at the diff from 2.7.2. It includes a
>> changelog entry that seems to describe a fix for the bug, and a
>> corresponding patch that seems to be the fix itself. Actually, it seems like
>> it just disabled the specific optimization that didn't work (it could be
>> affected by overflow sometimes, apparently), but left the rest of strength
>> reduction intact.
>
>That's what I knew.  It would be interesting to see whether GCC 2.8 
>corrected the bug as God intended, i.e. without disabling a broad class 
>of optimizations.  This thought was actually the reason for my question.  
>I thought that we may be missing some optimizations due to old fears.
Actually, that was my point. I thought it *didn't* disable a broad class of
optimizations, just the *specific* one that didn't work, i.e. one little
piece of code. But as always, UTSL is the complete answer. And yes it would
be nice if GCC 2.8 can make the optimization work correctly (whatever it is :).

Nate Eldredge
eldredge AT ap DOT net