https://issues.dlang.org/show_bug.cgi?id=21539
--- Comment #2 from Walter Bright <bugzi...@digitalmars.com> --- Looks like: https://github.com/dlang/dmd/pull/9078 is the cause. Rewriting the example to: import std.stdio; mixin template T() { alias X = .File; } mixin T; and it works. --