Qt 5.12.5 is latest release for the LTS branch of QT, so it makes sense to update to this version.

Original Description

I had originally installed Qt 5.12.3 from another overlay. The QtWebEngine package provided was patched but the source of that patch could not be traced upstream. The latest files available in tree did not contain this patching. Re-building this package chewed up a lot of time and was a roadblock for me for the 1.4 Release.

A couple of days ago, I set to resolve the issues in the ebuild. I found that the system-icu flag was not a cause of problems. Errors I encountered related back to a missing #pragma once or other form of header guarding statements. Also, a lamda function was misnamed. Once I patched the 5.12.3 sources with these changes, the build finally completed late today.

I do not think the ebuild should be merged into the tree without further testing/corroboration that the issues have been fixed. There is a QtBugs issue opened on my findings (Qt Bugs Issue 77402)

If someone has the time/bandwidth, request testing of attached ebuild/patch files to verify this builds. USE="alsa spellcheck system-ffmpeg system-icu widgets"