Re: Build error for wcwidth and gcvt

[Kota Uchida <uchan0+newlib at gmail dot com>]

Thank you, Corinna.
I fixed my patch and re-submitted it.
https://sourceware.org/ml/newlib/2019/msg00330.html

I also fixed a patch for compilation error of efgcvt.c
following Yaakov's advice.
https://sourceware.org/ml/newlib/2019/msg00329.html

2019年7月23日(火) 16:56 Corinna Vinschen <vinschen@redhat.com>:
>
> On Jul 23 08:26, Kota Uchida wrote:
> > I got understand about wchar_t data sizes.
> > I fixed my patch and sent it:
> > https://sourceware.org/ml/newlib/2019/msg00322.html
> >
> > > The header should be kept untouched, of course.
> >
> > The header file (wchar.h) must be fixed in order to
> > match types between the header and .c file.
>
> No, the header needs to stick to wchar_t since that's what the standard
> says.  The wint_t for Cygwin is an internal implementation detail.
>
>
> Corinna
>
>
> >
> > On Mon, Jul 22, 2019 at 7:51 PM Corinna Vinschen <vinschen@redhat.com> wrote:
> > >
> > > On Jul 22 11:46, Thomas Wolff wrote:
> > > > On 22.07.2019 11:04, Corinna Vinschen wrote:
> > > > > On Jul 20 17:50, Kota Uchida wrote:
> > > > > > Hi All,
> > > > > >
> > > > > > This is my first mail to newlib community.
> > > > > > I've send this mail because I found some build errors
> > > > > > on newlib's master branch.
> > > > > >
> > > > > > Cygwin: unbreak the build with GCC 7
> > > > > > 6b7723a83032bd355d3c529d957fe209cb35b4d9
> > > > > >
> > > > > > I encountered 2 errors about wcwidth and gcvt.
> > > > > > I've pushed simple patches to forked repository:
> > > > > > https://github.com/uchan-nos/newlib-cygwin/commits/fix-build
> > > > The first patch is not correct:
> > > > - wcwidth (const wint_t wc)
> > > > + wcwidth (const wchar_t wc)
> > > >
> > > > Note the manual page.
> > > > Even if you see the wchar_t definition for Linux/POSIX, note that wchar_t
> > > > has 32 bits there.
> > > > On cygwin, however, wchar_t was defined to have only 16 bits, corresponding
> > > > to the Windows UTF-16 encoding.
> > > > The wcwidth parameter type wint_t is needed to support width enquiries for
> > > > non-BMP characters;
> > > > changing it would seriously deprive the function of part of its
> > > > capabilities.
> > > > Thomas
> > >
> > > We might need a generic and a Cygwin-specific definition in the source, i.e.
> > >
> > >   #ifdef __CYGWIN__
> > >   use wint_t
> > >   #else
> > >   use wchar_t
> > >   #endif
> > >
> > > The header should be kept untouched, of course.
> > >
> > >
> > > Corinna
> > >
> > > --
> > > Corinna Vinschen
> > > Cygwin Maintainer
> > > Red Hat
>
> --
> Corinna Vinschen
> Cygwin Maintainer
> Red Hat