diff --git a/lib/ExtUtils/MM_Unix.pm b/lib/ExtUtils/MM_Unix.pm
index 570fe52b3..decc3d472 100644
--- a/lib/ExtUtils/MM_Unix.pm
+++ b/lib/ExtUtils/MM_Unix.pm
@@ -3967,7 +3967,7 @@ sub tool_xsubpp {
     }
 
 
-    $self->{XSPROTOARG} = "" unless defined $self->{XSPROTOARG};
+    $self->{XSPROTOARG} = "-noprototypes" unless defined $self->{XSPROTOARG};
     $self->tool_xsubpp_emit($xsdir, \@tmdeps, \@tmargs);
 }