Use "use warnings" rather than -w on the #! line.

packaging/patch-update

-#!/usr/bin/perl -w
+#!/usr/bin/perl
 # This script is used to turn one or more of the "patch/*" branches
 # into one or more diffs in the "patches" directory.  Pass the option
 # --gen if you want generated files in the diffs.  Pass the name of
@@ -6,6 +6,7 @@
 # diffs.
 
 use strict;
+use warnings;
 use Getopt::Long;
 
 my $patches_dir = 'patches';

packaging/release-rsync

-#!/usr/bin/perl -w
+#!/usr/bin/perl
 use strict;
+use warnings;
 
 # This script expects the directory ~/samba-rsync-ftp to exist and to be a
 # copy of the /home/ftp/pub/rsync dir on samba.org.  When the script is done,

packaging/var-checker

-#!/usr/bin/perl -w
+#!/usr/bin/perl
 # This script checks the *.c files for extraneous "extern" variables,
 # for vars that are defined but not used, and for inconsistent array
 # sizes.  Run it from inside the main rsync directory.
 
 use strict;
+use warnings;
 
 my %add_syscall_c = map { $_ => 1 } qw( t_stub.c t_unsafe.c tls.c trimslash.c );
 my %add_compat_c = map { $_ => 1 } qw( t_stub.c tls.c trimslash.c wildtest.c );

support/git-set-file-times

-#!/usr/bin/perl -w
+#!/usr/bin/perl
 use strict;
+use warnings;
 
 # Sets mtime and atime of files to the latest commit time in git.
 #

support/instant-rsyncd

-#!/bin/bash -e
+#!/bin/bash
 
 # instant-rsyncd lets you quickly set up and start a simple, unprivileged rsync
 # daemon with a single module in the current directory.  I've found it
@@ -12,6 +12,8 @@
 # and once to log in to test the daemon.
 # -- Matt McCutchen <matt@mattmccutchen.net>
 
+set -e
+
 dir="$(pwd)"
 
 echo

support/mnt-excl

-#!/usr/bin/perl -w
+#!/usr/bin/perl
 # This script takes a command-line arg of a source directory
 # that will be passed to rsync, and generates a set of excludes
 # that will exclude all mount points from the list.  This is
@@ -25,6 +25,7 @@
 # awk '{print $2}' /proc/mounts | rsync -f 'merge,/- -' host:/dir /dest/
 
 use strict;
+use warnings;
 use Cwd 'abs_path';
 
 my $file = '/proc/mounts';