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From: "colin.pitrat+gcc at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug c/64442] -O1 modify output of a simple computation with rounding
Date: Tue, 30 Dec 2014 15:44:00 -0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=64442

Colin Pitrat <colin.pitrat+gcc at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|UNCONFIRMED                 |RESOLVED
         Resolution|---                         |INVALID

--- Comment #4 from Colin Pitrat <colin.pitrat+gcc at gmail dot com> ---
OK thank you, sorry for the bothering !

In the mean time I also discovered -Og that appeared in gcc 4.8, that provides
optimization compatible with debugging and that have the same behavior. This
allows me to have the same result with the release and the debug build, which
is what was the issue for me.

I'm still surprised by the fact that -Og or -O1 seems to be more than just the
list of -f flags it activates, as providing only them doesn't trigger this same
behaviour. I couldn't find another responsible flag in the difference I found
in the output of --help=warnings,target,params,c or common

Closing this bug as invalid.

Regards,
Colin