/usr/share/vim/vim80/ftplugin/gdb.vim is in vim-runtime 2:8.0.1453-1ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 | " Vim filetype plugin file
" Language: gdb
" Maintainer: Michaël Peeters <NOSPAMm.vim@noekeon.org>
" Last Changed: 26 Oct 2017
if exists("b:did_ftplugin") | finish | endif
let b:did_ftplugin = 1
setlocal commentstring=#%s
" Undo the stuff we changed.
let b:undo_ftplugin = "setlocal cms<"
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