[gdb] Fix whitespace in NEWS

Fix this:
...
$ empty=$(git hash-object -t tree /dev/null)
$ git diff-index --check $empty gdb/NEWS
gdb/NEWS:1874: space before tab in indent.
+ 	                          [--basename | --dirname]
...
and add the file to the clean list in
gdb/contrib/check-whitespace-pre-commit.py.

[ I'm not sure if NEWS has an official style.

There are no settings for NEWS in .gitattributes, so the whitespace attribute
defaults to trailing-space (shorthand for blank-at-eol, blank-at-eof) and
space-before-tab.

We could require either spaces only (tab-in-indent) in gdb/.gitattributes:
...
NEWS	whitespace=space-before-tab,tab-in-indent,trailing-space
...
or tab style (indent-with-non-tab):
...
NEWS	whitespace=space-before-tab,indent-with-non-tab,trailing-space
...

For tab-in-indent, we get:
...
$ git diff-index --check $empty gdb/NEWS  | wc -l
228
...
and for indent-with-non-tab instead:
...
$ git diff-index --check $empty gdb/NEWS  | wc -l
40
...
so the more common style seems to be tab style.

But I'm leaving this as is for now. ]

2 files changed, 2 insertions, 2 deletions

diff --git a/gdb/NEWS b/gdb/NEWS
index 381536c..3b0a7f7 100644
--- a/gdb/NEWS
+++ b/gdb/NEWS
@@ -1881,7 +1881,7 @@ GNU/Linux/OpenRISC		or1k*-*-linux*
     the '-force' flag of the CLI's "cond" command.
 
  ** '-file-list-exec-source-files [--group-by-objfile]
- 	                          [--basename | --dirname]
+	                          [--basename | --dirname]
                                   [--] [REGEXP]'
 
     The existing -file-list-exec-source-files command now takes an
diff --git a/gdb/contrib/check-whitespace-pre-commit.py b/gdb/contrib/check-whitespace-pre-commit.py
index d7fa45d..9d82f77 100755
--- a/gdb/contrib/check-whitespace-pre-commit.py
+++ b/gdb/contrib/check-whitespace-pre-commit.py
@@ -19,7 +19,7 @@ import subprocess
 import sys
 
 re_clean = re.compile(
-    "(^(gdb/testsuite/|gdbsupport/|gdbserver/)|[.](m4|ac|def|[chly])$)"
+    "(^(gdb/testsuite/|gdbsupport/|gdbserver/)|[.](m4|ac|def|[chly])$|NEWS)"
 )
 re_clean_exclude = re.compile("^(gdb/symfile.c|gdb/cli/cli-cmds.c)$")