https://gcc.gnu.org/bugzilla/show_bug.cgi?id=91312
--- Comment #3 from Kostas Sotiropoulos <kosotiro at yahoo dot gr> --- (In reply to Andrew Pinski from comment #2) > THis is not a bug, In C, "i += MACRO;" is equivant to: > i = i + MACRO. > And since you are using a type smaller than int, it is prompted to int. > > NOTE there might be another bug associated with this one. 1)In order to remove the warning we should only do the following: i = (unsigned char)(i + MACRO)? 2)Why if we want to cast like this: i += (unsigned char)MACRO, i on the right side of expression is not also casted to unsigned char (I mean the second i of expanded expression i = i + MACRO? 3)What do you mean with your NOTE can you please elaborate a bit more? 4) If we expand and cast the expression we will probably have not so optimized produced code by the compiler, should we? Thank you, Kostas
