Re: libmpeg2 fix for ppc

[Havard Eidnes <he%NetBSD.org@localhost>]

>> configure for libmpeg2 manages to not define HAVE_ALTIVEC_H,
>> because, apparently,
>>
>> typedef vector int t;
>> int
>> main()
>> {
>>         vec_ld(0, (unsigned char*) 0);
>> }
>>
>> manages to build without errors.
>
> From what lib does the linker resolve vec_ld in the test compile?

I don't think it's linked, only compiled with "cc -c".  And that
succeeds if invoked with -maltivec.

However, I perceive the "HAVE_ALTIVEC_H" macro to express whether
the <altivec.h> header is available on the current system, and
then it makes sense to me to *first* test the above with that
include added, and secondarily to test without.

As it stands now, the result of the autoconf test is "yes, this
host has altivec via -maltivec, but does not need <altivec.h>",
and the latter part of that conclusion turns out to be false, as
it causes the build to fail.

Regards,

- Håvard