diff --git a/Library/Homebrew/requirements.rb b/Library/Homebrew/requirements.rb
index 485b86f4ee..4ca9496eb1 100644
--- a/Library/Homebrew/requirements.rb
+++ b/Library/Homebrew/requirements.rb
@@ -108,6 +108,7 @@ class MPIDependency < Requirement
     @lang_list = lang_list
     @non_functional = []
     @unknown_langs = []
+    super()
   end
 
   def mpi_wrapper_works? compiler
@@ -184,6 +185,7 @@ class ConflictRequirement < Requirement
     @formula = formula
     @name = name
     @opts = opts
+    super()
   end
 
   def message