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Re: Signedness of wchar_t and wint_t leads to problems with gcc -Wsign-conversion
- From: Szabolcs Nagy <szabolcs dot nagy at arm dot com>
- To: <mtk dot manpages at gmail dot com>, Andreas Schwab <schwab at suse dot de>
- Cc: <nd at arm dot com>, "libc-alpha at sourceware dot org" <libc-alpha at sourceware dot org>, Igor Liferenko <igor dot liferenko at gmail dot com>
- Date: Mon, 21 Nov 2016 13:01:11 +0000
- Subject: Re: Signedness of wchar_t and wint_t leads to problems with gcc -Wsign-conversion
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On 21/11/16 12:54, Michael Kerrisk (man-pages) wrote:
> So, I'm not quite clear on the point that you are making in your
> second point. Given code such as:
>
> wchar_t w;
> ...
> if (iswlower((wint_t) w) ....
>
> Do you mean that the standards are saying that casting to wint_t here
> is guaranteed to be correct? I can't see the line of reasoning that
> leads there.
an implementation is allowed to support wide
characters with >=0 value only (independently
of signedness of wchar_t).
in which case (wint_t)w is ok.