Hi Guix and T G-R, I think i verified that the upstream patch will fix the failing freecad build at least.
guix refresh qtbase --list-dependents reports 377 dependents on qtbase though. So that leads to option 1. > 1. If more than 300 qtbase dependents currently build fine: apply > the fix[0] to a separate qtbase/fixed package, and use it (on > master) in all packages that currently fail to build because of > this bug. Once Qt 5.12.8 comes out in April (or we upgrade > everything to 5.14), the /fixed variant can be removed on the > staging branch. My only problem is that I am not sure which packages are failing because of the bug. Any idea how to figure it out? Thanks, John