I noticed this with the update of ffmpeg-chromium-106, possibly other versions and/or packages using ffmpeg are also impacted, I didn't verify that. The issue is the same as described here: https://aur.archlinux.org/packages/lib32-ffmpeg#comment-900502 I downgraded vulkan-headers to stable and now it compiles again.
Please include the full build.log & emerge --info.
The bug has been closed via the following commit(s): https://gitweb.gentoo.org/repo/gentoo.git/commit/?id=810cb8902cdd9f880104d9d6b99ff3023799a2ca commit 810cb8902cdd9f880104d9d6b99ff3023799a2ca Author: James Le Cuirot <chewi@gentoo.org> AuthorDate: 2023-02-09 21:49:23 +0000 Commit: James Le Cuirot <chewi@gentoo.org> CommitDate: 2023-02-09 21:49:23 +0000 media-video/ffmpeg-chromium: Apply upstream fix for newer vulkan-headers Closes: https://bugs.gentoo.org/893502 Signed-off-by: James Le Cuirot <chewi@gentoo.org> .../ffmpeg-chromium/ffmpeg-chromium-102.ebuild | 1 + .../ffmpeg-chromium/ffmpeg-chromium-106.ebuild | 1 + .../files/ffmpeg-chromium-vk-headers.patch | 36 ++++++++++++++++++++++ 3 files changed, 38 insertions(+)