Hi, Attached are 3 files, 'f1.cpp', 'f2.cpp', and 'TAGS'. I'm using the development 28.0.50 version on Windows. Start emacs and: 1. C-x 2 (split-window-below) 2. C-x C-f (find-file) "f1.cpp" in the upper window 3. C-x C-f (find-file) "f2.cpp" in the lower window 4. left-mouse click in the upper window top left (location of the search start) 5. (tags-search) the string "_cu" using the attached TAGS file Tags search (regexp): _cu 6. M-, (fileloop-continue) until reaching "All files processed" The matches are on lines: f1.cpp: 7, 25, 65, 104, 121 f2.cpp: 7, 25, 65, 104, 121 (both f1 and f2 have identical contents). 7. In the upper window, switch to buffer f1.cpp and go to line 53: 8. mark line 53 and move down to line 72, then delete the selection: You're deleting this: case ECall::DPI::_pow_: { IT::IAcc _one ( R()->c1.CastTo( _ty ) ); IT::IAcc _zero( R()->c0.CastTo( _ty ) ); IT::IAcc _condBase ( _theFunction.Arg(0) .EqEq( IT::FlagsOfIKind(), _zero ) ); IT::IAcc _condExp ( _theFunction.Arg(1) .LT( IT::FlagsOfIKind(), _zero ) ); // Specialize to capture `0 ** 0` and return 1. IT::IfHlpr _testSpcl ( _cu, _condBase .AndAnd (IT::FlagsOfIKind(), _condExp), IT::List() ); _testSpcl.True() << _one.Return(); _body << _testSpcl; break; } 9. M-< (beginning-of-buffer) in the upper window ("f1.cpp") 10. (tags-search) the string "_cu" Tags search (regexp): _cu 11. M-, (fileloop-continue) until reaching "All files processed" The matches are on lines: 7, 25, 85, 102, 115, 121 NOTE 115 is wrong, it is this line that does not contain "_cu" # ifdef C_FILE_GENERATOR NOTE only 1 of the "_cu"s was deleted so instead of 10 occurrences there should be 9 BUT it only found 6. In GNU Emacs 28.0.50 (build 1, x86_64-w64-mingw32) of 2021-01-15 built on CIRROCUMULUS Repository revision: f45be48ddbde00610e1e08fca6590dcf24a4e1b5 Repository branch: master Windowing system distributor 'Microsoft Corp.', version 10.0.19042 System Description: Microsoft Windows 10 Enterprise (v10.0.2009.19042.985) Configured using: 'configure --without-dbus --without-compress-install -C 'CFLAGS=-O2 -static -g3' PKG_CONFIG_PATH=/mingw64/lib/pkgconfig' Configured features: ACL GIF GMP GNUTLS HARFBUZZ JPEG JSON LCMS2 LIBXML2 MODULES NOTIFY W32NOTIFY PDUMPER PNG RSVG SOUND THREADS TIFF TOOLKIT_SCROLL_BARS XPM ZLIB Important settings: value of $LANG: ENU locale-coding-system: cp1252 Major mode: Fundamental Minor modes in effect: shell-dirtrack-mode: t show-paren-mode: t tooltip-mode: t global-eldoc-mode: t electric-indent-mode: t mouse-wheel-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. Features: (shadow sort mail-extr emacsbug message rmc puny dired dired-loaddefs rfc822 mml mml-sec epa epg epg-config gnus-util rmail rmail-loaddefs text-property-search mm-decode mm-bodies mm-encode mail-parse rfc2231 mailabbrev gmm-utils mailheader sendmail rfc2047 rfc2045 ietf-drums mm-util mail-prsvr mail-utils misearch multi-isearch two-column help-mode thingatpt etags fileloop generator xref project time-date pcmpl-unix web-mode advice derived edmacro kmacro shell pcomplete comint ansi-color ring printing ps-print ps-print-loaddefs ps-def lpr paren cc-mode cc-fonts cc-guess cc-menus cc-cmds cc-styles cc-align cc-engine cc-vars cc-defs finder-inf tex-site info package easymenu browse-url url url-proxy url-privacy url-expand url-methods url-history url-cookie url-domsuf url-util mailcap url-handlers url-parse auth-source cl-seq eieio eieio-core cl-macs eieio-loaddefs password-cache json subr-x map url-vars seq byte-opt gv bytecomp byte-compile cconv cl-loaddefs cl-lib iso-transl tooltip eldoc electric uniquify ediff-hook vc-hooks lisp-float-type 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 elisp-mode lisp-mode prog-mode register page tab-bar menu-bar rfn-eshadow isearch timer select scroll-bar mouse jit-lock font-lock syntax facemenu font-core term/tty-colors frame minibuffer cl-generic 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 charscript charprop case-table epa-hook jka-cmpr-hook help simple abbrev obarray cl-preloaded nadvice button loaddefs faces cus-face macroexp files window text-properties overlay sha1 md5 base64 format env code-pages mule custom widget hashtable-print-readable backquote threads w32notify w32 lcms2 multi-tty make-network-process emacs) Memory information: ((conses 16 192149 7744) (symbols 48 14547 1) (strings 32 50102 1978) (string-bytes 1 1608447) (vectors 16 21762) (vector-slots 8 294115 19624) (floats 8 263 356) (intervals 56 3062 0) (buffers 984 18))