Re: wchar_t and -fshort-wchar

[Rich Felker <dalias@libc.org>]

On Wed, Feb 18, 2015 at 12:53:37PM +0200, Sergey Dmitrouk wrote:
> Hi,
> 
> musl seems to build fine with -fshort-wchar, but when client applications
> are built against musl all uses of wide character literals fail due to wide
> type defined internally by a compiler differs from the type of `wchar_t` in
> musl headers.
> 
> I faced this on ARM where `wchar_t` is defined as `unsigned int` by
> musl but it's `unsigned short` from compilers point of view.  I'd expect
> similar issues with other targets.
> 
> Would it make sense to use `__WCHAR_TYPE__` for `wchar_t` when it's
> available (it's already used for i386, but for different reason)?
> Presumably, as compiler is responsible for creating wide literals, libc
> would better agree with it on the type.
> 
> Of course, this makes sense only if you intend to support builds with
> `-fshort-wchar` flag, which are not very common I believe.

musl does not support configurations with under-sized definitions of
types like 16-bit wchar_t or 32-bit off_t. Only the sizes that can
represent the full range of values are supported. musl does however
have the C11 uchar.h functions which can operate on char16_t, so you
could use char16_t and the corresponding c16 conversion functions
instead of the wc versions if that helps. What are you trying to
achieve?

Rich