Re: [PATCH] cmake/build.mk: Hide non-buildlink3 libraries from cmake

[Taylor R Campbell <riastradh%NetBSD.org@localhost>]

> Date: Thu, 16 Jan 2025 13:06:14 +0000
> From: Taylor R Campbell <riastradh%NetBSD.org@localhost>
> 
> Revised cmake patch: this one sets CMAKE_PREFIX_PATH,
> CMAKE_INCLUDE_PATH, and CMAKE_LIBRARY_PATH as environment variables
> rather than as cmake variables.
> [...]
> The attached updated patch series also tweaks qt5-qtbase/buildlink3.mk
> files to put ${BUILDLINK_DIR}/qt5 rather than ${PREFIX}/qt5 into
> CMAKE_PREFIX_PATH, and similarly for qt6.  And it puts ${PREFIX} in
> CMAKE_IGNORE_PREFIX_PATH to stop cmake from directly searching for any
> files under ${PREFIX} (though it may still find things via, e.g.,
> pkg-config).

I committed this, but I deferred the CMAKE_IGNORE_PREFIX_PATH and
qt5/qt6 BUILDLINK_DIR parts to another day.  I've also addressed all
the fallout I found in my bulk builds (as well as a bunch of other
issues that I investigated just to make sure they weren't cmake
fallout).

I'll keep an eye on the bulk builds, but feel free to let me know if
there's any other fallout from this that I've miss.  Typical failure
mode is that cmake can't find dependencies during configure that it
used to be able to find.