compiling code for different machines

[Brian Dessent]

Brian Dessent wrote:

> > I want to create binarys on this systems that I can use on
> > all boxes. So i tried to compile my gcc on my i686 machine
> > using

Upon re-reading your question, I might have misunderstood.

If you are asking about recompiling gcc, then that is not necessary at
all.  Gcc has but a single x86 backend, and it can generate code for the
entire spectrum of x86 -march options listed in the manual.  So there is
no need to rebuild gcc to generate 486 code.  Just compile your software
with your normal gcc with -march=486.

The only potential reason that you might want to recompile gcc is to
change its *default* -march.  This is the -march that it will use if
none is specified, and this can be set by the --with-arch configure
option when building gcc.  However, going to the trouble of rebuilding
gcc just to change its default -march is massive overkill.  You could
e.g. just set CFLAGS in your .bashrc so that the desired -march is
always supplied.  Or you could use a config.site file to give
site-specific autoconf flags and specify CFLAGS there.  Or you could
just edit gcc's specs file and add the desired -march there.  None of
these require rebuilding the compiler.

Brian