cgal4 @4.14.3_0: build failure due to zlib and conflict

[dstrubbe (David Strubbe)]

I got two build failures for cgal4, which were related to finding the /usr/lib version of zlib rather than the macports one, and due to a conflict with the cgal port about a CMake file. Both are fixed in the attached patch.

[michaelld (Michael Dickens)]

You should be able to specify just -DZLIB_ROOT=${prefix} for the configure args (or without the -D for configure environment), and CMake should then find the MP version, without all of the specifics. See for example ​https://trac.macports.org/ticket/60896 and ​https://trac.macports.org/ticket/60938 ...

[michaelld (Michael Dickens)]

That said, I'll take a look at the base CMake to see what changed. 3.17 worked in this regard; 3.18 isn't. Should be simple to fix one the change is tracked down ...

[kencu (Ken)]

this same issue keeps coming up with zlib and libiconv so far at least. Something must have changed in the way that cmake searches for packages.

[kencu (Ken)]

It seem that <​https://cmake.org/cmake/help/latest/variable/CMAKE_SYSTEM_PREFIX_PATH.html#variable:CMAKE_SYSTEM_PREFIX_PATH> used to find /opt/local first, but now does not.

Is that possible? The way we patch it <​https://github.com/macports/macports-ports/commit/33927d6e899167f60bae7a7f11dc5d9b14f0bda5#diff-edbc510ec38eb78a21bff80a0416e7a3> has changed a bit.

[michaelld (Michael Dickens)]

Hmmm ... I don't see how that commit changed it to remove the MP PREFIX ... but it might have. I can certainly look into tweaking the CMAKE_SYSTEM_PREFIX_PATH so that MP PREFIX comes as first as it can be, not knowing if CMake might tweak it after we set it ... of course.

[michaelld (Michael Dickens)]

How about in Darwin.cmake, I append the following:

list(INSERT CMAKE_SYSTEM_PREFIX_PATH 0
  __PREFIX__ # MacPorts
)

This would make the MP prefix first in the search paths for the SYSTEM prefix path. I'll try this & see if it works, by removing the ZLIB_ROOT additions from the other commits, and of those now work again with those changes, then I think it's worth more testing.

[michaelld (Michael Dickens)]

Yup ... looks like that does the trick ... I'll do a PR for it shortly ...

[michaelld (Michael Dickens)]

In bc5236adc362f024aebd41ca198130bc40db49d0/macports-ports (master):

cmake: tweak patch to more appropriately set CMAKE_SYSTEM_PREFIX_PATH

==> prepend MacPorts' prefix instead of appending it

Should fix issues such as #60951 , #60938 , #60896 ; without having to set ZLIB_ROOT and other variables

[michaelld (Michael Dickens)]

I bypassed the PR stage ... this change just makes so much sense & is small enough that I just pushed it directly. In my testing, it removes the need for the changes for the other issues. Please update the test this port to verify.

[dstrubbe (David Strubbe)]

Ok. I think marking the conflict with the old cgal port is valuable too.

[michaelld (Michael Dickens)]

Replying to dstrubbe:

Ok. I think marking the conflict with the old cgal port is valuable too.

@dstrubbe one issue at a time ...

Can someone confirm that my CMake tweak fixes this issue? It does for me in my testing. Best to have others test as well.

[Veence (Vincent)]

Am I supposed to do anything? Or is the fix going to be implemented at the CMAKE level?

[michaelld (Michael Dickens)]

If the current cgal4 builds correctly, then this issue can be closed IMHO, since it was "fixed" elsewhere. IIRC, I tested and found that it builds for me with the noted changes I made to the cmake port.

[Veence (Vincent)]

OK. I’m closing this. Please re-open if needed.