Several regex warnings when installing latest postgres update

[Jeff Lane ]

Noticed during an update of PostgreSQL via apt-get this evening:

Setting up postgresql-9.5 (9.5.0-3) ...
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Unescaped left brace in regex is deprecated, passed through in regex; marked by <-- HERE in m/(?<!\\)\${ <-- HERE ([^}]+)}/ at /usr/sbin/pam_getenv line 78.
Creating new cluster 9.5/main ...
  config /etc/postgresql/9.5/main
  data /var/lib/postgresql/9.5/main
  locale en_US.UTF-8
  socket /var/run/postgresql
  port 5432
update-alternatives: using /usr/share/postgresql/9.5/man/man1/postmaster.1.gz to provide /usr/share/man/man1/postmaster.1.gz (postmaster.1.gz) in auto mode
Setting up postgresql (9.5+172) ...

Installation is fine, I think, just that is a lot of warnings to appear during an update.

ProblemType: Bug
DistroRelease: Ubuntu 16.04
Package: postgresql 9.5+172
ProcVersionSignature: Ubuntu 4.4.0-2.16-generic 4.4.0
Uname: Linux 4.4.0-2-generic x86_64
ApportVersion: 2.20-0ubuntu2
Architecture: amd64
CurrentDesktop: Unity
Date: Mon Feb 15 20:59:02 2016
InstallationDate: Installed on 2016-02-12 (3 days ago)
InstallationMedia: Ubuntu 16.04 LTS "Xenial Xerus" - Alpha amd64 (20160210)
PackageArchitecture: all
SourcePackage: postgresql-common
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Jb (jebsolutions)]

Disclaimer, I am not a regex expert.

But changing line 78 of /usr/sbin/pam_getenv from

$val =~ s/(?<!\\)\${([^}]+)}/$ENV{$1}||""/eg;

to

$val =~ s/(?<!\\)\$\{([^}]+)\}/$ENV{$1}||""/eg;

seems to eliminate the error?

[mevidvash (mevidvash)]

Jb (jebsolutions) it's seems it stop the problem thank you !