diff --git a/site-modules/profile/lib/puppet/functions/flatten_to_argument_list.rb b/site-modules/profile/lib/puppet/functions/flatten_to_argument_list.rb
index a718f8da..ff193ad0 100644
--- a/site-modules/profile/lib/puppet/functions/flatten_to_argument_list.rb
+++ b/site-modules/profile/lib/puppet/functions/flatten_to_argument_list.rb
@@ -1,35 +1,37 @@
 require 'shellwords'
 
 Puppet::Functions.create_function(:flatten_to_argument_list) do
   dispatch :flatten_to_argument_list do
     param 'Hash', :variable
     optional_param 'String', :escaping_type
     optional_param 'String', :prefix
     return_type 'Array[String]'
   end
 
   def flatten_to_argument_list(variable, escaping_type = 'systemd', prefix = '--')
     ret = []
     variable.each do |key, value|
       arg = "#{prefix}#{key}".gsub('_', '-')
       if Hash === value
         ret += flatten_to_argument_list(value, escaping_type, "#{arg}.")
       else
         if value == true
           ret.push(arg)
         else
           if escaping_type == 'systemd'
             # This replaces every backslash with four backslashes to please
             # systemd's EnvironmentFile escaping. Yes, gsub needs four
             # backslashes per output backslash.
-            value.gsub!('\\', '\\\\\\\\\\\\\\\\')
+            escaped_value = value.gsub('\\', '\\\\\\\\\\\\\\\\')
           elsif escaping_type == 'shell'
-            value = Shellwords.escape(value)
+            escaped_value = Shellwords.escape(value)
+          else
+            escaped_value = value
           end
-          ret.push("#{arg}=#{value}")
+          ret.push("#{arg}=#{escaped_value}")
         end
       end
     end
     ret
   end
 end