This is the mail archive of the
libc-alpha@sources.redhat.com
mailing list for the glibc project.
Re: The usage of _dl_hwcap and dl_hwcap_mask is confusing
On Wed, Jun 25, 2003 at 12:34:33AM -0700, Roland McGrath wrote:
> > Why shouldn't glibc support SSE when it is the part of the hardware?
> > Should a user application be allowed to use SSE when it is available?
> > I think it should be (GL(dl_hwcap) & HWCAP_I386_XMM).
>
> The purpose of _dl_hwcap_mask is to mask that value, controllable with
> LD_HWCAP_MASK to request omitting hwcap-specific code as if the machine
> didn't have that capability. HWCAP_I386_XMM needs to be added to
> HWCAP_IMPORTANT as well since it's now used.
My question is why you don't want to support XMM when it is available.
What advantage do you gain by that? Adding HWCAP_I386_XMM to
HWCAP_IMPORTANT also means now ld.so will seach for the "sse" directory
for shared libraries.
H.J.