D-Programming-Language/dmd — pull request #4107 by 9rnsr (2014-11-03 04:35:28+00:00)
Title: Issue 12929 - Empty union followed by field causes ICE due to offset of 0.

https://issues.dlang.org/show_bug.cgi?id=12929

@WalterBright If I'm not mistaken, empty anonymous struct/union does not have to have 1 byte size in C11.