Re: Fix GCC's preferred stack alignment to match psABI

[David Laight <david%l8s.co.uk@localhost>]

On Sun, Sep 16, 2012 at 06:36:09PM +0100, David Laight wrote:
> On Tue, Sep 11, 2012 at 10:22:48PM +0200, Joerg Sonnenberger wrote:
> > Hi all,
> > the attached patch consists of two parts. The first part ensures that
> > GCC honours the SYSV ABI on i386 as used by NetBSD. The second part
> > adjusts the alignment of stack variables, so that double and complex
> > double as well as long long are not aligned to 64bit by default, if the
> > stack alignment is smaller. This avoids triggering unnecessary stack
> > reliagnments.
> 
> What was wrong with enabling -mstackrealign by default?

ie building gcc with:
#define STACK_REALIGN_DEFAULT 1

Or possibly explicitly specifying -mstackrealign when building libraries.
It really shouldn't matter for program binaries themselves.

        David

-- 
David Laight: david%l8s.co.uk@localhost