[Bug c/23087] Misleading warning, "... differ in signedness"

[joseph at codesourcery dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=23087

--- Comment #16 from joseph at codesourcery dot com <joseph at codesourcery dot com> ---
Well, an additional

note: 'char' and 'signed char' are different types

(or similar in the unsigned case) could be added in the case where the 
types have the same representation, one is char and the other is signed or 
unsigned char.  Or the wording of the original warning could be refined in 
that case.  But I don't think the less-specific wording about incompatible 
types would be appropriate here, or that the warning should be enabled 
more widely than the general signedness case (if anything, this case is 
less serious than that one).