[Mesa-dev] [PATCHv2] configure.ac: roll up a program for the sse4.1 check

[Matt Turner]

On Sat, Nov 15, 2014 at 10:37 AM, Emil Velikov <emil.l.velikov at gmail.com> wrote:
> So when checking/building sse code we have three possibilities:
>  1 Old compiler, throws an error when using -msse*
>  2 New compiler, user disables sse* (-mno-sse*)
>  3 New compiler, user doesn't disable sse
>
> The original code, added code for #1 but not #2. Later on we patched
> around the lack of handling #2 by wrapping the code in __SSE4_1__.
> Yet it lead to a missing/undefined symbol in case of #1 or #2, which
> might cause an issue for #2 when using the i965 driver.
>
> A bit later we "fixed" the undefined symbol by using #1, rather than
> updating it to handle #2. With this commit we set things straight :)
>
> To top it all up, conventions state that in case of conflicting
> (-enable-foo -disable-foo) options, the latter one takes precedence.
> Thus we need to make sure to prepend -msse4.1 to CFLAGS in our test.
>
> v2: Clean the #includes. Suggested by Ilia, Matt & Siavash.
>
> Cc: Siavash Eliasi <siavashserver at gmail.com>
> Cc: Matt Turner <mattst88 at gmail.com>

Get rid of the Ccs if people have responded before you commit. :)
> Tested-by: David Heidelberg <david at ixit.cz>
> Tested-by: Siavash Eliasi <siavashserver at gmail.com>
> Reviewed-by: Matt Turner <mattst88 at gmail.com>
> Signed-off-by: Emil Velikov <emil.l.velikov at gmail.com>