Failure to build Gtk4 because of missing vulkan headers

Vulkan headers not found After configuring, meson reports that vulkan dependency is satisfied:

Dependency vulkan found: YES 1.2.153 (cached)

but building by invoking ninja fails with this error:

In file included from ../gdk/gdkinternals.h:38,
                 from ../gdk/gdkdrop.c:32:
../gdk/gdkdisplayprivate.h:31:10: fatal error: vulkan/vulkan.h: No such file or directory
   31 | #include <vulkan/vulkan.h>
      |          ^~~~~~~~~~~~~~~~~
compilation terminated.

the gtk4 meson.build file already include a test for vulkan

# Check for Vulkan support
# Uses meson's custom vulkan dependency searching. Set the VULKAN_SDK env var
# to use a custom path for the Vulkan SDK. Bugs that are found with it should
# be reported upstream and fixed.
vulkan_dep = dependency('vulkan', required: get_option('vulkan'))

I’m on Manjaro/Gnome 3.38/X11 system. meson version: 0.56.0 ninja version: 1.10.1 Python 3.8.6

After installing vulkan-headers package the failure is resolved.

[eli-schwartz]

This dependency troubles and confuses me.

vulkan.pc, as distributed by the KhronosGroup, provides a dependency for the Vulkan Loader, not the Vulkan Headers. So the results you got are technically correct – the SDK cannot be called “vulkan” as it clashes with the Vulkan ICD Loader.

[martinhath]

Okay, I think I got it. This is basically what I meant with “This seems to be deferred to the package managers of the distributions”, as in the way the files are packaged and distributed should make sure that if you have the .pc file you also get the libraries and headers and so on, which is the case with GLFW, since it includes everything, but not with Vulkan, since there are separate packages for the loader and the headers, and the .pc file comes with the loader package.

I guess one could make a distinction being able to link with a library and having the header file so that you compile against it, and that it’s not clear if having a .pc file for the library should always imply that you can both, so maybe this is Khronos’ take? (to be clear, I think it’s perfectly clear and that Vulkan is in the wrong here)

Actually checking for individual header files is called “hacky and inaccurate heuristics”, but usually works relatively okayish.

Right, I wasn’t actually suggesting that Meson should do this, I just wasn’t sure how any build system looking at .pc files were supposed to infer which headers are available since there is no information in them about headers.

Anyways, thanks for the clarifications!