X.Org Server 1.18 Will Require Updated Video Drivers

The in-development X.Org Server 1.18 once again breaks the video driver ABI. Rebuilding the driver for compatibility isn't much of an issue for the open-source DDX drivers or the frequently-updated NVIDIA proprietary driver, but it could spell out months of waiting for those depending on the AMD Catalyst driver and wanting to use xorg-server 1.18.

X.Org Server 1.18 is running behind schedule and much belated if compared to the original communication that v1.18 would be on a quicker release cycle. However, X.Org Server 1.18 will bring with it many mode-setting driver and GLAMOR improvements along with new PRIME features and RandR 1.5.

Like most xorg-server release cycles, the video driver ABI ended up breaking during the development cycle and now the ABI version number was bumped today in Git to v20. "Commit 90db5edf119187f8b1b9207c8c384d6cd7ef9edc modified the signature of StartPixmapTrackingProcPtr, so drivers implementing that need to use the updated definition."

It's not an issue really for open-source drivers or even the NVIDIA proprietary driver as their Unix graphics team tends to implement support for new xorg-server releases well before their public debut. Heck, it was NVIDIA's Aaron Plattner that even detected the video ABI breakage and bumped it in Git. The main headache just continually comes down to AMD Catalyst / fglrx in that the support doesn't come for months after the server release or until the time that Ubuntu (generally) is getting ready to send off a new release, which is general why AMD generally needs to send Canonical a beta driver for Ubuntu packaging (or in the other cases, to provide updated kernel support).

With Ubuntu 15.10 sticking to X.Org Server 1.17, AMD won't be hard pressed for supporting xorg-server 1.18 quickly, so it could end up being months after the debut of the new X.Org Server before it will be handled by their binary blob.