Date: Fri, 24 Oct 2025 18:43:15 +0900 (JST)
Message-Id: <20251024.184315.1449345234035166124.ishii@postgresql.org>
To: pgsql@j-davis.com
Cc: pgsql-hackers@postgresql.org
Subject: Re: C11: should we use char32_t for unicode code points?
From: Tatsuo Ishii <ishii@postgresql.org>
In-Reply-To: <bedcc93d06203dfd89815b10f815ca2de8626e85.camel@j-davis.com>
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> Now that we're using C11, should we use char32_t for unicode code
> points?
> =

> Right now, we use pg_wchar for two purposes:=A0
> =

>   1. to abstract away some problems with wchar_t on platforms where
> it's 16 bits; and
>   2. hold unicode code point values
> =

> In UTF8, they are are equivalent and can be freely cast back and fort=
h,
> but not necessarily in other encodings. That can be confusing in some=

> contexts. Attached is a patch to use char32_t for the second purpose.=

> =

> Both are equivalent to uint32, so there's no functional change and no=

> actual typechecking, it's just for readability.
> =

> Is this helpful, or needless code churn?

Unless char32_t is solely used for the Unicode code point data, I
think it would be better to define something like "pg_unicode" and use
it instead of directly using char32_t because it would be cleaner for
code readers.

Best regards,
--
Tatsuo Ishii
SRA OSS K.K.
English: http://www.sraoss.co.jp/index_en/
Japanese:http://www.sraoss.co.jp