[sword-devel] Compile Options

Luke Mauldin sword-devel@crosswire.org
Tue, 12 Jun 2001 18:33:23 -0500

Hello, I am a sword library user and I also happen to keep up with gcc 
development.  I noticed that on i86 processors sword is compiled using the 
-m486 flag.  This sets up the compile to produce instructions for a 486 and 
it also sets code alignment patterns, etc... for a 486.  However, the code 
alignment patterns and the instructions patterns used by modern 
processors(i586 and greater) are VERY different from the 486.  It is in fact 
better for these newer processors to optimize for a 386 than for a 486!  It 
is my suggestion that the -m486 option be removed and -march=i386 -mcpu=i686 
added.  This will allow all processors from a 386 up to use sword but it 
optimizes sword for a 686 processor.  These are the default compile values 
that most Linux distributions use(including RedHat).  Using -march=i586 and 
-mcpu=i686 like the Mandrake distribution would offer even higher performance 
at the cost of allowing only Pentium and newer processors to run the sword