1 files changed, 5 insertions, 1 deletions
diff --git a/kernel.rb b/kernel.rb
index de20fffcf9..9cc58bc1d9 100644
--- a/kernel.rb
+++ b/kernel.rb
@@ -169,6 +169,10 @@ module Kernel
   #     Float("123.0_badstring", exception: false)  #=> nil
   #
   def Float(arg, exception: true)
-    Primitive.rb_f_float(arg, exception)
+    if Primitive.mandatory_only?
+      Primitive.rb_f_float1(arg)
+    else
+      Primitive.rb_f_float(arg, exception)
+    end
   end
 end