Hideously stupid error message when you have a module name that doesn't match its filename. Simple cases are omitted, but if you have any reasonably large project and change a module declaration from, say, "module core.Args;" to "module core.args;", you get this complaint.
Comment #1 by bearophile_hugs — 2010-07-17T10:10:13Z
See also bug 3972
Comment #2 by andrej.mitrovich — 2012-12-19T03:23:30Z