diff --git a/lib/sass/script/value/base.rb b/lib/sass/script/value/base.rb
index <HASH>..<HASH> 100644
--- a/lib/sass/script/value/base.rb
+++ b/lib/sass/script/value/base.rb
@@ -20,7 +20,7 @@ module Sass::Script::Value
     #
     # @param value [Object] The object for \{#value}
     def initialize(value = nil)
-      @value = value.freeze
+      @value = value.freeze unless value.nil?
     end
 
     # Sets the options hash for this node,
Don't freeze nil.

In Ruby, the nil singleton object is not frozen. Freezing it breaks
some other gems.

~$ irb
<I> :<I> > nil.frozen?
 => false

Conveniently, the `unless` syntax leaves `@value` as good ol' nil,
so there's no need for a ternary.