bug#65995: 29.1; \cC does not match some CJK IDEOGRAPHs

bug#65995: 29.1; \cC does not match some CJK IDEOGRAPHs

[awrhygty]

The Unicode ranges U+3400..U+4DBF and U+4E00..U+9FFF are completely
filled with CJK UNIFIED IDEOGRAPHs, and all characters in them should be
matched by \cC.
But characters in ranges U+4DB6..U+4DBF and U+9FD6..U+9FFF are not
matched by \cC.

(string-match "\\cC" (apply #'string (number-sequence #x4DB6 #x4DBF)))
=>nil
(string-match "\\cC" (apply #'string (number-sequence #x9FD6 #x9FFF)))
=>nil



In GNU Emacs 29.1 (build 2, x86_64-w64-mingw32) of 2023-08-02 built on
 AVALON
Windowing system distributor 'Microsoft Corp.', version 10.0.19045
System Description: Microsoft Windows 10 Pro (v10.0.2009.19045.3448)

Configured using:
 'configure --with-modules --without-dbus --with-native-compilation=aot
 --without-compress-install --with-tree-sitter CFLAGS=-O2'

Configured features:
ACL GIF GMP GNUTLS HARFBUZZ JPEG JSON LCMS2 LIBXML2 MODULES NATIVE_COMP
NOTIFY W32NOTIFY PDUMPER PNG RSVG SOUND SQLITE3 THREADS TIFF
TOOLKIT_SCROLL_BARS TREE_SITTER WEBP XPM ZLIB

(NATIVE_COMP present but libgccjit not available)

Important settings:
  value of $LANG: JPN
  locale-coding-system: cp932

Major mode: Lisp Interaction

Minor modes in effect:
  highlight-changes-visible-mode: t
  tooltip-mode: t
  global-eldoc-mode: t
  eldoc-mode: t
  show-paren-mode: t
  electric-indent-mode: t
  mouse-wheel-mode: t
  tool-bar-mode: t
  menu-bar-mode: t
  file-name-shadow-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  blink-cursor-mode: t
  line-number-mode: t
  indent-tabs-mode: t
  transient-mark-mode: t
  auto-composition-mode: t
  auto-encryption-mode: t
  auto-compression-mode: t

Load-path shadows:
None found.

Features:
(misearch multi-isearch comp comp-cstr warnings icons rx emoji-labels
emoji multisession sqlite transient format-spec edmacro kmacro cl-extra
gnutls network-stream nsm mailalias smtpmail textsec uni-scripts url
url-proxy url-privacy url-expand url-methods url-history url-cookie
generate-lisp-file url-domsuf url-util url-parse auth-source cl-seq
eieio eieio-core cl-macs json map url-vars idna-mapping ucs-normalize
uni-confusable textsec-check cl-print byte-opt gv bytecomp byte-compile
debug backtrace find-func hilit-chg wid-edit thingatpt help-fns
radix-tree help-mode pp shadow sort mail-extr emacsbug message mailcap
yank-media puny dired dired-loaddefs rfc822 mml mml-sec password-cache
epa derived epg rfc6068 epg-config gnus-util text-property-search
time-date subr-x mm-decode mm-bodies mm-encode mail-parse rfc2231
mailabbrev gmm-utils mailheader cl-loaddefs cl-lib sendmail rfc2047
rfc2045 ietf-drums mm-util mail-prsvr mail-utils term/bobcat japan-util
rmc iso-transl tooltip cconv eldoc paren electric uniquify ediff-hook
vc-hooks lisp-float-type elisp-mode mwheel dos-w32 ls-lisp disp-table
term/w32-win w32-win w32-vars term/common-win tool-bar dnd fontset image
regexp-opt fringe tabulated-list replace newcomment text-mode lisp-mode
prog-mode register page tab-bar menu-bar rfn-eshadow isearch easymenu
timer select scroll-bar mouse jit-lock font-lock syntax font-core
term/tty-colors frame minibuffer nadvice seq simple cl-generic
indonesian philippine cham georgian utf-8-lang misc-lang vietnamese
tibetan thai tai-viet lao korean japanese eucjp-ms cp51932 hebrew greek
romanian slovak czech european ethiopic indian cyrillic chinese
composite emoji-zwj charscript charprop case-table epa-hook
jka-cmpr-hook help abbrev obarray oclosure cl-preloaded button loaddefs
theme-loaddefs faces cus-face macroexp files window text-properties
overlay sha1 md5 base64 format env code-pages mule custom widget keymap
hashtable-print-readable backquote threads w32notify w32 lcms2 multi-tty
make-network-process native-compile emacs)

Memory information:
((conses 16 282629 44922)
 (symbols 48 11822 4)
 (strings 32 63635 4534)
 (string-bytes 1 1299035)
 (vectors 16 52952)
 (vector-slots 8 1587592 175200)
 (floats 8 69 384)
 (intervals 56 3562 356)
 (buffers 984 17))

bug#65995: 29.1; \cC does not match some CJK IDEOGRAPHs

[Eli Zaretskii]

> From: awrhygty@outlook.com
> Date: Fri, 15 Sep 2023 21:31:29 +0900
> 
> 
> The Unicode ranges U+3400..U+4DBF and U+4E00..U+9FFF are completely
> filled with CJK UNIFIED IDEOGRAPHs, and all characters in them should be
> matched by \cC.
> But characters in ranges U+4DB6..U+4DBF and U+9FD6..U+9FFF are not
> matched by \cC.
> 
> (string-match "\\cC" (apply #'string (number-sequence #x4DB6 #x4DBF)))
> =>nil
> (string-match "\\cC" (apply #'string (number-sequence #x9FD6 #x9FFF)))
> =>nil

Thanks, now fixed on the emacs-29 branch, and closing the bug.