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Re: (-Os versus -O2 relation) Was: case where gcc generates bigger binaries than MSVC
- To: egcs at egcs dot cygnus dot com, jh at suse dot cz, law at cygnus dot com, mat at lcs dot mit dot edu
- Subject: Re: (-Os versus -O2 relation) Was: case where gcc generates bigger binaries than MSVC
- From: Mike Stump <mrs at windriver dot com>
- Date: Thu, 11 May 2000 13:15:22 -0700 (PDT)
> Date: Thu, 11 May 2000 10:25:16 +0200
> From: Jan Hubicka <jh@suse.cz>
> To: egcs@egcs.cygnus.com, law@cygnus.com, mat@lcs.mit.edu
> I am not sure about DATA_ALIGNMENT. The decision IMO that needs to
> be made is whether we want -O2 and -Os code to be combined.
There are alignments that are mandated by the ABI, don't follow them,
and there isn't compatibility. Those cannot change with -Os. The
optional/extra alignments that don't interfere (except with
performance) with interworking of ABI compliant code, should be
affected by -Os.
If gcc smears these two cases together in a port file, then we need to
unsmear them and expose the difference to the compiler. We could try
and have the port files make use of the -Os flag, but in the end, I
don't think that would be better.