The following code used to compile as previously it was accept-invalid bug: --- void main() { enum e = "" ~ a; } --- Nevertheless marked as regression as it causes ICE on code used to compile.
*** Issue 10412 has been marked as a duplicate of this issue. ***
Commit pushed to master at https://github.com/D-Programming-Language/dmd https://github.com/D-Programming-Language/dmd/commit/990a6c661fac04d5f404da548885762337df4a9b Fix issue 10397 ICE with __error in concatenation ErrorExp was allowing implicit conversions in some cases, because it is derived from IntegerExp! This made errors become un-errors again in some circumstances.