https://issues.dlang.org/show_bug.cgi?id=13284 --- Comment #1 from Kenji Hara <k.hara.pg at gmail.com> --- With 2.055 - 2.065 and git-head, the code produces same result: core.exception.AssertError at test.d(14): Unknown message! Which dmd version had produced "Got a!" message? --