They are supposed to match C. But they don't for unary operators + - ~, and as
far as I can tell never did.
https://issues.dlang.org/show_bug.cgi?id=16997
https://issues.dlang.org/show_bug.cgi?id=17637
Note that the spec says:
"Note: unlike in C and C++, the usual integral promotions are not performed
prior to the complement operation."
http://dlang.org/spec/expression.html#complement_expressions
Where did that come from?
And the spec says nothing about unary - or unary +.
http://dlang.org/spec/expression.html#unary-expression
It's been like this at least since D1, both the code and the Spec.
So, we have a choice:
1. Fix it so it matches C, as has been generally promised. Fixing it will break
existing code such as:
https://github.com/dlang/phobos/pull/5646
but worse, it may silently break code. I don't know of a reasonable way to
detect this.
2. Codify existing practice, since it has been that way forever. Not matching C
has caused problems, see 16997 and 17637. It may cause more serious silent
problems for people converting C code to D code.
