1 files changed, 4 insertions, 2 deletions
diff --git a/activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb b/activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb
index 5fbd79d118..dd5fd607a2 100644
--- a/activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb
+++ b/activerecord/lib/active_record/associations/builder/has_and_belongs_to_many.rb
@@ -76,8 +76,10 @@ module ActiveRecord::Associations::Builder # :nodoc:
           left_model.retrieve_connection
         end
 
-        def self.primary_key
-          false
+        private
+
+        def self.suppress_composite_primary_key(pk)
+          pk unless pk.is_a?(Array)
         end
       }