[Development] 5.7.0-rc compile error

[Tim Blechmann]

> Are you trying out of the source builds ?

that's my usual workflow as i need to compile static and dynamic libs
from the same source folder ...


> I opened a ticket yesterday for this, specifically Qt3D, but it can
> compiles if you run from the root tree on the source.

it also compiles fine when retrying a few times ... but that's not
exactly an elegant workflow :P