Custom x86 ABI

Ian Lance Taylor
Wed Nov 6 01:01:00 GMT 2013

On Mon, Nov 4, 2013 at 3:59 AM, David Kaplan <> wrote:
> I've just build a cross-compiler with the i586-elf target which I need
> for my project.
> I was wondering: is there a way to build a custom ABI such that the
> EBX (or any other register) is never used by GCC?
> If so, how do I go about doing it?

If the only change you want to make is to have GCC never use %ebx,
then compile with -ffixed-ebx.


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