On Mon, 21 Nov 2016 13:05:24 +0100 "Michael Kerrisk (man-pages)" < mtk.manpa...@gmail.com> wrote: > Upstream maintainer here. > > I added the missing include. > > But I am unsure what to do about the other point (regarding gcc > -Wconversion). There is an analogous situation with islower() and > similar functions, where the solution is described by an update I > recently added for the upcoming upstream release > > The standards require that the argument c for these functions is > either EOF or a value that is representable in the type unsigned > char. If the argument c is of type char, it must be cast to > unsigned char, as in the following example: > > char c; > ... > res = toupper((unsigned char) c); > > This is necessary because char may be the equivalent signed char, > in which case a byte where the top bit is set would be sign > extended when converting to int, yielding a value that is outside > the range of unsigned char. > > However, we don't have a similar solution for iswlower(), because > there is no "(unsigned wchar_t)" cast. And casting to (wint_t) seems > incorrect to me, because if wchar_t is a signed type smaller than > wint_t, then sign extension could occur. > > I could be wrong, but it seems like an implementation bug that one of > these types is signed and the other is unsigned. > > Cheers, > > Michael > >
tamtam
