media-libs/lv2 creates symbolic links from include dir to libdir (in lv2 used for bundles, which mostly consists of headers and ttl files). But with config option --copy-headers it will copy targets instead of linking them. Unmerge followed by emerge have no problems, but emerging may cause unexpected result: - If prior install had symlinks and new has dirs, new install has symlinks as before. - But if it was dirs first and symlinks next - same dirs are here but empty, while symlink has its name with appended numeric extension as for backup. In this case unmerging will leave entire tree unremoved (for lv2 - /usr/include/lv2 with all dirs and symlink backups), requiring manual removal to get it back properly working. Reproducible: Always Steps to Reproduce: 1. Emerge current lv2 ebuild from gentoo: /usr/include/lv2 should have symlinks. 2. Modify ebuild, adding --copy-headers to config options. Reemerge. There are still symbolic links. 3. Unmerge & emerge. There are just directories now, /usr/include/lv2/atom is not empty. 4. Remove --copy-headers from ebuild. Actual Results: Subdirectories in /usr/include/lv2 have same names, but empty. Symbolic links are here, but have .NNNN numeric ext appended to their filenames. Expected Results: 1. Either symbolic links should replace directories (like remove old before merge). 2. Or it's directories, whose names should have appended dot-numbers. I don't know if there are other packages where same replacement could occur. But still would be safer to count symlinks type itself as filetype rather than underlying filetype. I can't pre-assume this bug as minor, because there is no clear indication when such issue happens. I got sign of trouble when tried to reemerge all lilv & suil dependencies from gentoo releases after using own live ebuild, with lv2 ebuild having --copy-headers in src_configure(): sratom failed compilation due to missing lv2/atom/atom.h (see #789429, now closed).
