lichray added a comment. In https://reviews.llvm.org/D51268#1303217, @ldionne wrote:
> Please also update https://libcxx.llvm.org/cxx2a_status.html. Done. ================ Comment at: include/istream:601 + streamsize __n = __is.width(); + if (__n <= 0) + __n = numeric_limits<streamsize>::max() / sizeof(_CharT) - 1; ---------------- ldionne wrote: > Should this instead be `if (__n == 0)`? Can `width()` ever return a negative > number? cppreference says this about `streamsize`: > > > Except in the constructors of `std::strstreambuf`, negative values of > > `std::streamsize` are never used. > > I couldn't find a matching statement in the standard, however there's this > footnote in `30.5.2`: > > > `streamsize` is used in most places where ISO C would use `size_t`. Most of > > the uses of `streamsize` could use `size_t`, except for the `strstreambuf` > > constructors, which require negative values. It should probably be the > > signed type corresponding to `size_t` (which is what Posix.2 calls > > `ssize_t`). > > This does not clearly say that negative values are never used, but it does > suggest it. Maybe it's safer to still use `__n <= 0`. > My interpretation of 27.5.3.2 is that you can retrieve the value you set through `width(streamsize)`. And the wording here (unmodified) says "If `width()` is greater than zero, [...]," so the opposite should be `width() <= 0`. Repository: rCXX libc++ https://reviews.llvm.org/D51268 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
