Existing Guideline
Architecture Support
All Fedora packages must successfully compile and build into binary rpms on at least one supported primary architecture. Fedora packagers should make every effort to support all primary architectures.
Content, code which does not need to compile or build, and architecture independent code (noarch) are notable exceptions.
Proposal
Architecture Support
All Fedora packages must successfully compile and build into binary rpms on at least one supported primary architecture, unless the package is useful only on a secondary architecture (such as architecture-specific boot utilities, microcode loaders, or hardware configuration tools). Fedora packagers should make every effort to support all primary architectures.
Content, code which does not need to compile or build, and architecture independent code (noarch) are notable exceptions.
Discussion
See Talk:PackagingDrafts/MustBuildOnPrimaryArchitecture for rationale and discussion.