This was fixed in 5.14.0: $ cat foo #!/usr/bin/perl use warnings; use Devel::Peek; my $sOut; close(STDERR); open(STDERR, ">", \$sOut) or die "Can't redirect STDERR to \\\$sOut"; my $x; Dump $x; $ perl5.14.0 foo SV = NULL(0x0) at 0x826430 REFCNT = 1 FLAGS = (PADMY) $ perl5.12.0 foo Use of uninitialized value in subroutine entry at foo line 7. SV = NULL(0x0) at 0x822610 REFCNT = 1 FLAGS = (PADMY) -- Father ChrysostomosThread Next