Bug 11100

Summary: Fix wayland-scanner lookup for good, submit patches to upstreams
Product: [Build System, Metadata & Runtime] OE-Core Reporter: Jussi Kukkonen <jku>
Component: graphicsAssignee: Jussi Kukkonen <jku>
Status: RESOLVED WONTFIX QA Contact:
Severity: normal    
Priority: Medium+ CC: meta.mr.watcher, meta.watcher, ross.burton
Version: unspecified   
Target Milestone: 2.4 M4   
Hardware: x86   
OS: Multiple   
Whiteboard:
OS type for building Yocto: --- Type of Regression: ---
Verified: Documentation change: No (bug/feature does not impact docs)

Description Jussi Kukkonen 2017-02-23 13:39:00 UTC
The configure-time wayland-scanner lookup is broken for yocto in just about every project where it is done. We have many versions of this patch:

-        WAYLAND_PREFIX=`$PKG_CONFIG --variable=prefix wayland-client`
-        AC_PATH_PROG([WAYLAND_SCANNER], [wayland-scanner],,
-                     [${WAYLAND_PREFIX}/bin$PATH_SEPARATOR$PATH])
+        AC_PATH_PROG([WAYLAND_SCANNER], [wayland-scanner])

The upstream version is faulty because pkg-config will return target paths but we want to find a build-time wayland-scanner. On the other hand our version is not good for anyone else as it's very important to use the correct version of wayland-scanner and trusting PATH is _usually_ not a good way to achieve that.  

I don't think there is a way to get this to work automatically, so maybe the correct solution is to add "--with-wayland-scanner" option to every wayland-scanner using project. Should first agree about that with wayland folks, and then send a patch to all relevant projects.
Comment 1 Jussi Kukkonen 2017-06-08 11:32:13 UTC
Discussions on wayland and mesa mailing lists ongoing, so far no patches have been generally acceptable :(

Moving to M2 seems more realistic.
Comment 2 Jussi Kukkonen 2017-07-13 07:21:59 UTC
Moving onwards once more. I'll have another look later this summer and see if there's a chance of finding a solution that everyone accepts: The discussion in May-June was definitely not a success.
Comment 3 Jussi Kukkonen 2017-08-09 09:41:12 UTC
WONTFIXing: The attempt was worth it but ultimately did not succeed: Standardizing scanner lookups in weston/mesa/others will break some developers use case in at least one of the major projects and I wasn't able to sell the benefits of that so far. 

Spending more time on this now would not be a good use of time IMO: maybe trying again at a later point might work.