From b304a328dbe45061c919e7fb71bac2046886e7fc Mon Sep 17 00:00:00 2001
From: Doug Bell <doug@preaction.me>
Date: Sun, 21 Oct 2018 20:25:27 -0500
Subject: [PATCH 1/2] fix uninitialized warnings in stream

After `undef $self->{buffer}`, we can no longer call `length` on it in
Perl 5.10 (later Perls more usefully treat `undef` as empty without
warning). But, according to #1256, we can't just set `$self->{buffer}`
to the empty string without causing Perl to hold on to all the memory it
allocated for our buffer. So, we have to first `undef`, then set to
a defined value to prevent warnings from `length` on Perl 5.10.
---
 lib/Mojo/IOLoop/Stream.pm | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/lib/Mojo/IOLoop/Stream.pm b/lib/Mojo/IOLoop/Stream.pm
index 79e920fb2..068fa28a4 100644
--- a/lib/Mojo/IOLoop/Stream.pm
+++ b/lib/Mojo/IOLoop/Stream.pm
@@ -37,7 +37,7 @@ sub is_writing {
   return !!length($self->{buffer}) || $self->has_subscribers('drain');
 }
 
-sub new { shift->SUPER::new(handle => shift, timeout => 15) }
+sub new { shift->SUPER::new(handle => shift, buffer => '', timeout => 15) }
 
 sub start {
   my $self = shift;
@@ -122,7 +122,8 @@ sub _write {
   }
 
   # Clear the buffer to free the underlying SV* memory
-  undef $self->{buffer}, $self->emit('drain') unless length $self->{buffer};
+  undef $self->{buffer}, $self->{buffer} = '', $self->emit('drain')
+    unless length $self->{buffer};
   return if $self->is_writing;
   return $self->close if $self->{graceful};
   $self->reactor->watch($handle, !$self->{paused}, 0) if $self->{handle};

From fa06afe69c2025c698a54901643f160aeba3acad Mon Sep 17 00:00:00 2001
From: Doug Bell <doug@preaction.me>
Date: Sun, 21 Oct 2018 20:28:28 -0500
Subject: [PATCH 2/2] fix uninitialized warnings on Perl 5.10

Perl 5.10 warns when `length` is called on uninitialized values, so we
need to check for definedness first
---
 lib/Mojo/DOM/CSS.pm                     | 4 +++-
 lib/Mojolicious/Validator/Validation.pm | 2 +-
 2 files changed, 4 insertions(+), 2 deletions(-)

diff --git a/lib/Mojo/DOM/CSS.pm b/lib/Mojo/DOM/CSS.pm
index 463c50130..960cb5ab1 100644
--- a/lib/Mojo/DOM/CSS.pm
+++ b/lib/Mojo/DOM/CSS.pm
@@ -120,7 +120,9 @@ sub _compile {
     # Tag
     elsif ($css =~ /\G((?:$ESCAPE_RE\s|\\.|[^,.#:[ >~+])+)/gco) {
       my $alias = (my $name = $1) =~ s/^([^|]*)\|// && $1 ne '*' ? $1 : undef;
-      my $ns = length $alias ? $ns{$alias} // return [['invalid']] : $alias;
+      my $ns = defined $alias && length $alias
+        ? $ns{$alias} // return [['invalid']]
+        : $alias;
       push @$last, ['tag', $name eq '*' ? undef : _name($name), _unescape($ns)];
     }
 
diff --git a/lib/Mojolicious/Validator/Validation.pm b/lib/Mojolicious/Validator/Validation.pm
index 600e9e056..f505e800e 100644
--- a/lib/Mojolicious/Validator/Validation.pm
+++ b/lib/Mojolicious/Validator/Validation.pm
@@ -75,7 +75,7 @@ sub optional {
     @input = map { $self->$cb($name, $_) } @input;
   }
   $self->output->{$name} = ref $input eq 'ARRAY' ? \@input : $input[0]
-    if @input && !grep { !length } @input;
+    if @input && !grep { !defined || !length } @input;
 
   return $self->topic($name);
 }