drop-in type check for rb_define_global_function

We can check the function pointer passed to rb_define_global_function
like we do so in rb_define_method.  It turns out that almost anybody
is misunderstanding the API.

1 files changed, 3 insertions, 1 deletions

diff --git a/class.c b/class.c
index 05440f523b..2f1e9d7d5d 100644
--- a/class.c
+++ b/class.c
@@ -1767,7 +1767,9 @@ rb_define_module_function(VALUE module, const char *name, VALUE (*func)(ANYARGS)
     rb_define_singleton_method(module, name, func, argc);
 }
 
-
+#ifdef rb_define_global_function
+#undef rb_define_global_function
+#endif
 /*!
  * Defines a global function
  * \param name    name of the function