LLVM build system error on Windows (zstd)

[bluescarni]

Hello!

I am using an LLVM package maintained by the conda-forge project:

https://github.com/conda-forge/llvmdev-feedstock

Recently the LLVM package was updated from version 15.0.2 to 15.0.3. Additionally, the conda-forge developers backported this patch to their 15.0.3 package:

#58205

After the update, I am experiencing the following CMake failure (apparently related to zstd) in the CI of one of my projects:

https://github.com/bluescarni/heyoka/actions/runs/3300936955/jobs/5445923768#step:5:375

The failure seems to happen only on Windows systems (Linux and OSX are apparently fine).

The CMakeLists.txt of my project is, for reference, here:

https://github.com/bluescarni/heyoka/blob/master/CMakeLists.txt

Downgrading to llvm 15.0.2 fixes the issue.

[isuruf]

Looks like Findzstd.cmake requires downstream projects to include GNUInstallDirs cmake file.

[starseeker]

The CI log above is expired, but I'm seeing a zstd related build failure on Windows with LLVM 15.07 - is this still a problem? The failure I'm seeing appears to be related to the generated targets not having a property set correctly but still getting used - one of the table generation programs fails to link saying it's trying to use a NOTFOUND value for the library...

[mgorny]

If this is indeed about GNUInstallDirs, it's fixed by 5bbd598.