Bug 627884

Summary:	media-video/ffmpeg should automatically enable mmxext when sse is enabled
Product:	Gentoo Linux	Reporter:	Simon <simon.vanderveldt+gentoo>
Component:	Current packages	Assignee:	Gentoo Linux bug wranglers <bug-wranglers>
Status:	RESOLVED DUPLICATE
Severity:	normal
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
See Also:	https://bugs.gentoo.org/show_bug.cgi?id=559280
Whiteboard:
Package list:		Runtime testing required:	---

Description Simon 2017-08-14 20:07:05 UTC

Currently ffmpeg requires users to add mmxext to his/her CPU_FLAG_X86 when sse is enabled (which it is in the current default stage3 profile) which is a superfluous manual step since mmxext is a subset of sse.

ffmpeg should simply enable mmxext when cpu_flags_x86_sse is set so the user isn't bothered with this.

I ran into this issue with the CI for our overlay which runs automated emerge tests for new or changed ebuilds. Packages that depend on ffmpeg failed because of this.

See https://lists.gt.net/gentoo/amd64/299056#299056 for some extra explanation of the relation between mmxext and sse.

Comment 1 Brian Evans (RETIRED) gentoo-dev

2017-08-16 17:52:44 UTC

The stage3 make.conf has a bug where it should not list CPU_FLAGS_X86 at all.

The default profile has this correct..
profiles/arch/amd64/make.defaults:
CPU_FLAGS_X86="mmx mmxext sse sse2"

This is not unique to ffmpeg.

*** This bug has been marked as a duplicate of bug 544696 ***

Comment 2 Simon 2017-08-16 18:09:44 UTC

For future reference, the stage3 make.conf bug where it should not list CPU_FLAGS_X86 at all is https://bugs.gentoo.org/show_bug.cgi?id=608060