Subject: Re: [linux-audio-dev] LADSPA Update (http://www.ladspa.org)
From: Paul Barton-Davis (pbd_AT_Op.Net)
Date: Mon May 22 2000 - 14:49:05 EEST
> ______________________________________________________________________
> gcc -fPIC -DPIC -Wall -O2 -c -o my_plugin.o my_plugin.c
> ld -shared -o my_plugin.so my_plugin.o
> ______________________________________________________________________
From the info page for egcs 2.91.66:
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`-O2'
Optimize even more. GNU CC performs nearly all supported
optimizations that do not involve a space-speed tradeoff. The
compiler does not perform loop unrolling or function inlining when
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
my emphasis added
you specify `-O2'. As compared to `-O', this option increases
both compilation time and the performance of the generated code.
`-O2' turns on all optional optimizations except for loop unrolling
and function inlining. It also turns on the `-fforce-mem' option
on all machines and frame pointer elimination on machines where
doing so does not interfere with debugging.
`-O3'
Optimize yet more. `-O3' turns on all optimizations specified by
`-O2' and also turns on the `inline-functions' option.
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I humbly submit that we should be recommending the use of -O3.
--p
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