| Summary: | [Future EAPI] USE-dependent USE-flag masking | ||
|---|---|---|---|
| Product: | Gentoo Hosted Projects | Reporter: | Matt Turner <mattst88> |
| Component: | PMS/EAPI | Assignee: | PMS/EAPI <pms> |
| Status: | CONFIRMED --- | ||
| Severity: | normal | CC: | esigra, gentoo, sam |
| Priority: | Normal | ||
| Version: | unspecified | ||
| Hardware: | All | ||
| OS: | Linux | ||
| See Also: | https://bugs.gentoo.org/show_bug.cgi?id=609338 | ||
| Whiteboard: | |||
| Package list: | Runtime testing required: | --- | |
| Bug Depends on: | |||
| Bug Blocks: | 174380 | ||
A REQUIRED_USE extension might fit better, since that already specifies relationships between flags. |
It would be very nice to be able to specify that some USE flags are only meaningful in the presence of another USE flag. For example dev-vcs/git has IUSE=perforce which requires Python. Python support is not needed otherwise. By default some PYTHON_SINGLE_TARGET is enabled, and when the default target changes (e.g. in the profile) emerge --newuse will trigger a rebuild of dev-vcs/git even if USE=-perforce and thus Python isn't used. Just as a simple strawman, I'd propose some new syntax like IUSE="... perforce? ( python_single_target_python3_{7..9} ) ..." And emerge --verbose output would perhaps indicate that the flags are dependent: [ebuild R ] dev-vcs/git-2.26.3::gentoo USE="blksha1 curl gnome-keyring gpg iconv nls pcre pcre-jit perl subversion threads webdav -cgi -cvs -doc -emacs -highlight -mediawiki -mediawiki-experimental -perforce (-ppcsha1) -test -tk -xinetd" perforce? ( PYTHON_SINGLE_TARGET="-python3_7 -python3_8" ) Probably a better way to display that. Suggestions welcome.