The test https://github.com/mysql/mysql-server/blob/mysql-8.0.26/unittest/gunit/segfault-t.cc is failing when running under Gentoo sandbox (tested <3.0) because the expected output (.* UTC - mysqld got signal 6.*) isn't returned. I created https://github.com/Whissi/gentoo-mysql/commit/4c1931713d1e4a438252c3ee3d7d121fdaf0bfad to allow empty value for now. Not sure if we can improve sandbox to make this work.