python-setuptools-rust is already a buildroot-only package in CentOS 9 Stream, https://gitlab.com/redhat/centos-stream/rpms/python-setuptools-rust . Buildroot-only means that the package is available in the build environment. AFAIK I cannot add the package to epel9 without breaking stuff.

Can you work around the problem on your side, e.g. by installing the package in a virtual env?

> Can you work around the problem on your side, e.g. by installing the package in a virtual env?

Yes, that can be done.  Thanks for looking into it, and for the feedback.

This bug appears to have been reported against 'rawhide' during the Fedora Linux 39 development cycle.
Changing version to 39.

This is blocking building matrix-synapse in EPEL9.  Could this package be moved into CRB?

(In reply to Christian Heimes from comment #1)
> python-setuptools-rust is already a buildroot-only package in CentOS 9
> Stream, https://gitlab.com/redhat/centos-stream/rpms/python-setuptools-rust
> . Buildroot-only means that the package is available in the build
> environment. AFAIK I cannot add the package to epel9 without breaking stuff.

Buildroot-only packages are still eligible for EPEL because they are not shipped in the RHEL/CentOS distribution. EPEL users never see packages from the RHEL/CentOS buildroot, and RHEL/CentOS builders never see packages from EPEL.

For example, I maintain python-meson-python – a stripped-down version without features requiring patchelf is in the EL10 buildroot, and a full-featured version requiring patchelf is in EPEL10.

Ben is correct.  The RHEL/CentOS buildroot is not the same as the EPEL buildroot.  RHEL/CentOS buildroot packages are not available in the EPEL buildroot.  The EPEL buildroot is only baseos, appstream, and crb.  Early on for EPEL 9 we did try to build against the CentOS buildroot, and quickly ran into problems were packages had runtime dependencies on CentOS buildroot-only packages that were not available on systems trying to install the EPEL package.  The list of repos that each EPEL branch builds against is listed in the EPEL documentation.

https://docs.fedoraproject.org/en-US/epel/epel-policy/#_policy

The easiest solution would be to move the package to crb.  If that isn't an option for whatever reason, then the package is eligible for epel9 and can be built there instead.

This has also been requested for EPEL 10, or to be shipped in RHEL/CentOS 10 CRB, in bug 2316989.  In that bug Christian mentioned that Trivino has taken over maintenance of this package, so I'm reassigning this bug as such.

I realized that while we have discussed moving this to CRB to avoid duplicating the work in EPEL, we haven't yet formally requested it.  I've done that in this issue.

https://issues.redhat.com/browse/RHEL-66224

Thanks Carl, 
will process this ticket asap.

Note that putting python-setuptools-rust from buildroot-only into CRB would not help EPEL 9, in fact, it would be mostly useless.

Due to differences between the Rust RPM macros in RHEL 9 and 10, python-setuptools-rust *can* work the way it does in both RHEL 10 and EPEL 10, but putting it into CRB would make it work *only* for RHEL 9-ish builds, but not for EPEL 9 builds (due to unavoidable conflicts between rust-toolset and cargo-rpm-macros in RHEL < 10).

As such, I think the only viable solution would be to build a *different* python-setuptools-rust package in EPEL 9 (i.e. one that would actually allow building packages with it).