From: j DOT aldrich6 AT genie DOT com
Message-Id: <199607232317.AA191853833@relay1.geis.com>
Date: Tue, 23 Jul 96 22:57:00 UTC 0000
To: jan AT stack DOT urc DOT tue DOT nl
Cc: djgpp AT delorie DOT com
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Subject: Re: Size optimizations?

Reply to message 6380262    from JAN AT STACK DOT URC on 07/23/96  6:22AM


>And if I remember correctly dont use -O2 or -O3 or the compiler will make
>all funcitons calls inline!

Not all; just the ones that it thinks could provide a profitable speed
increase if inlined.  Also, the function can't be recursive or call certain
other kinds of functions.  And you only get this behavior when you
compile with -O3, or explictly specify '-finline-functions'.

A few notes about -O3:  It will slow down compilation by as much as 50%,
makes your executables quite a bit larger, and doesn't always improve
speed.  Unless you really, REALLY need speed and don't care about
anything else, the best optimization in terms of size and speed is -O2 (for
a moderate increase in compilation time.)  You could also theoretically
compile with -O3 and -fno-inline-functions, but it'd be pretty pointless.

For more info, read the gcc docs (gcc.inf).  (That's where I got all this. :)

John