Devel-Stacktrace version 1.24 is broken in conjunction with ( [perl-experimental] overlays ) Plack ebuild. Having 1.24 version of Devel::StackTrace installed will cause Plack to fail tests. ( At least for versions 0.9945 and 0.9946 , of which 0.9945 previously worked with earlier versions of Devel::StackTrace ) I have added Devel-Stacktrace version 1.25 to the perl-experimental overlay to satisfy this requirement temporarily for overlay users. However, its possible that this breakage affects other things I haven't tested for yet.
http://git.overlays.gentoo.org/gitweb/?p=proj/perl-overlay.git;a=commit;h=2655d6f4ba6396ce2f8233f81825d995c86421bc
Fixed. Thanks