Bug 684452

Summary:	media-video/ffmpeg-3.4.5 with sys-devel/gcc-8 and LTO - segmentation fault in ff_sine_window_init
Product:	Gentoo Linux	Reporter:	Alexander Miller <alex.miller>
Component:	Current packages	Assignee:	Gentoo Media-video project <media-video>
Status:	RESOLVED FIXED
Severity:	normal	Keywords:	PATCH
Priority:	Normal
Version:	unspecified
Hardware:	All
OS:	Linux
See Also:	https://gcc.gnu.org/bugzilla/show_bug.cgi?id=85132 https://trac.ffmpeg.org/ticket/7491
Whiteboard:
Package list:		Runtime testing required:	---
Attachments:	ffmpeg-3.4-segfault.patch

Description Alexander Miller 2019-04-27 00:01:40 UTC

Created attachment 574330 [details, diff]
ffmpeg-3.4-segfault.patch

After rebuilding media-video/ffmpeg-3.4.5 with a newer toolchain I got segfaults for most videos I tried to play (with ffplay or mplayer). I found the following upstream commit that addresses the issue but is missing from the 3.4 branch:
https://git.ffmpeg.org/gitweb/ffmpeg.git/commit/10f468156c0109a06854b5d672c5209a88923ce9
The attached patch based on that commit (changes to version.h disabled because they don't apply) fixes the issue for me.

The (unpatched) code writes to some arrays which are declared "const", so it's no surprise this causes segfaults. I think this should be fixed in the stable version even though it apparently works by chance with some toolchains and CFLAGS.

Comment 1 Alexis Ballier gentoo-dev

2019-10-02 10:31:33 UTC

This is fixed in 4.1.3 and later versions