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Re: Debug formats on Linux


As g77 has no inlining facility other than -O3, that option has to be used
with careful selection
of which subroutines are gathered together in files in which order.  Recent
snapshots have
overcome to a great extent the long standing problem about -O2  being
usually slower than -Os
on x86, apparently at the expense of bringing back more bugs.  Yes, the -m
options which are
supported in gcc are even more effective than with major commercial
compilers.
----- Original Message -----
From: "Robert Dewar" <dewar@gnat.com>
To: <Richard.Zidlicky@stud.informatik.uni-erlangen.de>;
<jfm2@club-internet.fr>
Cc: <gcc@gcc.gnu.org>
Sent: Sunday, November 05, 2000 4:27 AM
Subject: Re: Debug formats on Linux


> <<sure, I never use -O3 for my own programs - it is much better to use
> the inline keyword where apropriate and -funroll-loops where it helps.
> >>
>
> Our experience with Ada, where the extensive use of pragma Inline is
> encouraged and expected, is that -O3 often increases execution time,
> or increases space with no appreciable time gain, so we recommend
> against its use.


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