The current mono ebuild strips not only its own binaries but also the CLR lib images. The CLR lib images are not elf files and thus strip fudges these libs making them unusable for .net programs Reproducible: Always Steps to Reproduce: 1. :) FEATURES="-nostrip" emerge mono 2. Run any mono application eg mcs, monodoc, muine etc 3. Watch it die Actual Results: Error messages similer to ** (/usr/lib/mono/1.0/mcs.exe:14751): WARNING **: Could not find assembly System, references from /usr/lib/mono/1.0/mcs.exe (assemblyref_index=1) Major/Minor: 1,0 Build: 5000,0 Token: b77a5c561934e089 System error: No such file or directory Expected Results: For the application to work The best workaround is to use FEAURES="nostrip" when emerging mono (or to set nostrip off in make.conf
*** This bug has been marked as a duplicate of 73764 ***