[Issue 23865] duplicate alias not detected

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=23865

--- Comment #4 from Dlang Bot <dlang-bot at dlang.rocks> ---
dlang/dmd pull request #15771 "merge stable" was merged into master:

- 201fb344984dab010eb5c64e4c704423803c9789 by SixthDot:
  fix issue 23865 - ICE on attempt to insert an non overloadable symbol in a
set (#15681)

https://github.com/dlang/dmd/pull/15771

--