(Disclaimer: I have no knowledge whatsoever about the ISO-2022-JP encoding, and although this looks like a bug, I'm not sure this is actually a bug; I report this at the suggesion of Eli in bug#46859.) I downloaded the file [1], and converted it to the ISO-2022-JP encoding with iconv -t iso-2022-jp one.txt > iso-2022-jp.txt. The resulting file is attached to this bug report. It ends with two CRLFs, at byte offsets 2993 and 2995. However, after emacs -Q iso-2022-jp.txt, with M-: (goto-char (filepos-to-bufferpos POS 'exact)) we get: POS = 2991, 2992: last but one visible character (HIRAGANA LETTER RU) POS = 2993, 2994: last visible character (IDEOGRAPHIC FULL STOP) POS = 2995, 2996: first CRLF POS = 2997: second CRLF POS = 2998: point-max POS = 2999: first CRLF POS = 3000, 3001: second CRLF POS >= 3002: point-max I would have expected: POS = 2989, 2990: last but one visible character (HIRAGANA LETTER RU) POS = 2991, 2992: last visible character (IDEOGRAPHIC FULL STOP) POS = 2993, 2994: first CRLF POS = 2995, 2996: second CRLF POS >= 2997: point-max The opposite operation M-: (bufferpos-to-filepos (- (point) POS) 'exact) apparently also has bugs; its return values are not coherent with the above ones: POS = 0: 3003 POS = 1: 3001 POS = 2: 2999 POS = 3 (IDEOGRAPHIC FULL STOP): 2997 POS = 4 (HIRAGANA LETTER RU): 2995 I would have expected: POS = 0: 2997 POS = 1: 2995 POS = 2: 2993 POS = 3 (IDEOGRAPHIC FULL STOP): 2991 POS = 4 (HIRAGANA LETTER RU): 2989 [1] https://darza.com/ecbackend/vendor/symfony/mime/Tests/Fixtures/samples/charsets/iso-2022-jp/one.txt In GNU Emacs 27.1 (build 1, x86_64-pc-linux-gnu, GTK+ Version 3.24.23, cairo version 1.16.0) of 2020-11-08, modified by Debian built on x86-ubc-01 Windowing system distributor 'The X.Org Foundation', version 11.0.12010000 System Description: Debian GNU/Linux bullseye/sid Configured using: 'configure --build x86_64-linux-gnu --prefix=/usr --sharedstatedir=/var/lib --libexecdir=/usr/lib --localstatedir=/var/lib --infodir=/usr/share/info --mandir=/usr/share/man --enable-libsystemd --with-pop=yes --enable-locallisppath=/etc/emacs:/usr/local/share/emacs/27.1/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/27.1/site-lisp:/usr/share/emacs/site-lisp --with-sound=alsa --without-gconf --with-mailutils --build x86_64-linux-gnu --prefix=/usr --sharedstatedir=/var/lib --libexecdir=/usr/lib --localstatedir=/var/lib --infodir=/usr/share/info --mandir=/usr/share/man --enable-libsystemd --with-pop=yes --enable-locallisppath=/etc/emacs:/usr/local/share/emacs/27.1/site-lisp:/usr/local/share/emacs/site-lisp:/usr/share/emacs/27.1/site-lisp:/usr/share/emacs/site-lisp --with-sound=alsa --without-gconf --with-mailutils --with-cairo --with-x=yes --with-x-toolkit=gtk3 --with-toolkit-scroll-bars 'CFLAGS=-g -O2 -fdebug-prefix-map=/build/emacs-6jKC2B/emacs-27.1+1=. -fstack-protector-strong -Wformat -Werror=format-security -Wall' 'CPPFLAGS=-Wdate-time -D_FORTIFY_SOURCE=2' LDFLAGS=-Wl,-z,relro' Configured features: XPM JPEG TIFF GIF PNG RSVG CAIRO SOUND GPM DBUS GSETTINGS GLIB NOTIFY INOTIFY ACL LIBSELINUX GNUTLS LIBXML2 FREETYPE HARFBUZZ M17N_FLT LIBOTF ZLIB TOOLKIT_SCROLL_BARS GTK3 X11 XDBE XIM MODULES THREADS LIBSYSTEMD JSON PDUMPER LCMS2 GMP Important settings: value of $LANG: en_US.UTF-8 locale-coding-system: utf-8-unix Major mode: Lisp Interaction Minor modes in effect: tooltip-mode: t global-eldoc-mode: t eldoc-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 auto-composition-mode: t auto-encryption-mode: t auto-compression-mode: t line-number-mode: t transient-mark-mode: t Load-path shadows: None found. 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