Created attachment 563706 [details, diff] Add libressl USE flag The dependency of crypt USE flag is fixed to openssl. With the attached patch, perf built fine with libressl. Perf uses openssl only for computing MD5 or SHA1 checksum, so intricate compatibility problem isn't likely.
Libressl support has been discontinued in Gentoo. https://www.gentoo.org/support/news-items/2021-01-05-libressl-support-discontinued.html