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Re: notes on current atomics config and usage
On Thu, Jul 13, 2006 at 11:36:17PM -0700, Mark Mitchell wrote:
> Benjamin Kosnik wrote:
> > However, if they install this as a system lib then all users are going
> > to have to use the -march flag exactly as configured or else they'll
> > get synthesized calls to non-existent builtin atomics functions. (since
> > without the -march flag the default arch for this platform is i386,
> > with no builtin atomics.)
>
> I would say that this very sensible behavior. :-) As you say, they
> could instead hack the compiler to change the default arch, or they
> could provide multilibs for different variants.
It seems that we've just got to bite the bullet on the i386 problem.
The default arch needs to be i486, so we can count on having decent
locking primitives. If the user configures for i386, we can generate
multilibs, so the small proportion of users that need real 386 code
can support all combinations at the expense of extra build time and disk
space.