Ship libX11 / libXau / libxcb CDTs also on alma?

[h-vetinari]

Since conda-forge/python-feedstock@3052d25 we have the following yum_requirements.txt on the python feedstock:

#tk_needs_libx11_but_avoids_a_runtime_requirement_of_libx11_to_reduce_the_dependencies_of_python
libX11
#libxcb_is_a_dependency_of_libx11_but_deps_are_wrong_on_our_cdt
libxcb
libxau

I was wondering about both of these comments; IMO it'd be beneficial to build the required CDTs on alma, if it allows us to get rid of yum_requirements.txt for python? 🤔

Regarding the "but deps are wrong on our cdt", our metadata is coming unchanged from the upstream requirements, but we seem to miss stuff that's expressed not in terms of another rpm, but just the library itself. Compare the metadata here

with

cdt-builds/cdts/libx11-cos7-x86_64/meta.yaml

Lines 22 to 30 in d020455

	requirements:
	build:
	- libx11-common-cos7-x86_64 >=1.6.7 *_{{ cdt_build_number|int + 1000 }}
	host:
	- libx11-common-cos7-x86_64 >=1.6.7 *_{{ cdt_build_number|int + 1000 }}
	- sysroot_linux-64 2.17.*
	run:
	- libx11-common-cos7-x86_64 >=1.6.7 *_{{ cdt_build_number|int + 1000 }}
	- sysroot_linux-64 2.17.*

IOW, we pick up on libX11-common, but miss anything libxcb-related. If one follows the link on libxcb.so.1()(64bit) on pkgs.org, one ends up at libxcb, which itself has a similar situation

wheras we don't pick up that libxau dependency currently (this is for centos7 whereas the above metadata is for alma8; but it's pretty safe to assume that the problem is the same):

cdt-builds/cdts/libxcb-cos7-x86_64/meta.yaml

Lines 22 to 26 in d020455

	requirements:
	host:
	- sysroot_linux-64 2.17.*
	run:
	- sysroot_linux-64 2.17.*

It sounds like we might need to improve our metadata processing to fix that?

[isuruf]

IMO it'd be beneficial to build the required CDTs on alma, if it allows us to get rid of yum_requirements.txt for python? 🤔

Building CDTs does not help with getting rid of yum_requirements.txt. CDTs are for building, but you need real packages for running. (yum or conda)

[h-vetinari]

Sure, but there are cases where the respective run-portion never happens in our CI (like for python), and then the yum_requirements may not be needed at all.

It might even make sense to have a linter rule that everything in yum_requirements also shows up as a CDT in meta.yaml? That way we could avoid a lot of stale deps and other garbage in there.