Gentoo's Bugzilla –
Attachment 603454 Details for
Bug 705566sys-devel/llvm-9.0.1 on prefix - var/tmp/portage/sys-devel/llvm-9.0.1/work/llvm-abi_x86_64.amd64/bin/llvm-tblgen: error while loading shared libraries: libtinfo.so.5: cannot open shared object file: No such file or directory