This code compiles without no error. struct S { alias x this; // x is undefined, so should cause error } void main(){}
https://github.com/D-Programming-Language/dmd/pull/337
https://github.com/D-Programming-Language/dmd/commit/33844b7a3a9b0725708fc973d75e167cf813f0f3
*** Issue 6468 has been marked as a duplicate of this issue. ***