From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 48) id C14603860008; Wed, 14 Feb 2024 18:02:05 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org C14603860008 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1707933725; bh=5cxssi4CGpsUTyUuxZEqNHN/7Xc5d2wLGTKS/ct3tiQ=; h=From:To:Subject:Date:In-Reply-To:References:From; b=D3FA4tZtrB4RI7ZpZMbnRBYGph1cEr/bu1ljsKp259oP56rODM96jY96J2oyv14Na +0oKqzSDwU+DNCILBQl4S9RKvCzmJWRx2Aupx4hJhJFu7YzqJFauntexEIRrm/jnpP LDR3J01350+FHrB7jmVn0OFlpvkwhAF3to96kTK4= From: "julesbertholet at quoi dot xyz" To: libc-locales@sourceware.org Subject: [Bug localedata/31370] wcwidth() does not treat DEFAULT_IGNORABLE_CODE_POINTs as zero-width Date: Wed, 14 Feb 2024 18:02:03 +0000 X-Bugzilla-Reason: CC X-Bugzilla-Type: changed X-Bugzilla-Watch-Reason: None X-Bugzilla-Product: glibc X-Bugzilla-Component: localedata X-Bugzilla-Version: 2.40 X-Bugzilla-Keywords: X-Bugzilla-Severity: normal X-Bugzilla-Who: julesbertholet at quoi dot xyz X-Bugzilla-Status: NEW X-Bugzilla-Resolution: X-Bugzilla-Priority: P2 X-Bugzilla-Assigned-To: maiku.fabian at gmail dot com X-Bugzilla-Target-Milestone: --- X-Bugzilla-Flags: X-Bugzilla-Changed-Fields: Message-ID: In-Reply-To: References: Content-Type: text/plain; charset="UTF-8" Content-Transfer-Encoding: quoted-printable X-Bugzilla-URL: http://sourceware.org/bugzilla/ Auto-Submitted: auto-generated MIME-Version: 1.0 List-Id: https://sourceware.org/bugzilla/show_bug.cgi?id=3D31370 --- Comment #3 from Jules Bertholet --- > Please provide a patch to libc-alpha@sourceware.org https://sourceware.org/pipermail/libc-alpha/2024-February/154574.html > Please also provide justification for the zero width by quoting another i= mplementation that also provides zero width e.g. CLDR. CLDR doesn't address width issues at all, this is defined by Unicode itself. The Unicode Standard, version 15.0, =C2=A75.21 - Characters Ignored for Dis= play : > The list of characters which should be ignored for display in fallback re= ndering is given by a character property: Default_Ignorable_Code_Point (DI)= . Those characters include almost all format characters, all variation sele= ctors, and a few other exceptional characters, such as Hangul fillers. The = exact list is defined in DerivedCoreProperties.txt in the Unicode Character= Database. U+115F HANGUL CHOSEONG FILLER needs a carveout due to the unique behavior of the conjoining Korean jamo characters. One composed Hangul "syllable block" like =E1=84=91=E1=85=B1=E1=86=B6 is made up of two to three individual comp= onent characters, or "jamo". These are all assigned an `East_Asian_Width` of `Wide` by Unicode, which wo= uld normally mean they would all be assigned width 2 by glibc; a combination of (leading choseong jamo) + (medial jungseong jamo) + (trailing jongseong jam= o) would then have width 2 + 2 + 2 =3D 6. However, glibc (and other wcwidth implementations) special-cases jungseong and jongseong, assigning them all width 0, to ensure that the complete block has width 2 + 0 + 0 =3D 2 as it should. U+115F is meant for use in syllable blocks that are intentionally missing a leading jamo; it must be assigned a width of 2 even though it has= no visible display to ensure that the complete block has width 2. You can read more about Unicode jamo in the Unicode spec, sections 3.12 and 18.6 . --=20 You are receiving this mail because: You are on the CC list for the bug.=