1 files changed, 1 insertions, 0 deletions
diff --git a/intern.h b/intern.h
index c4a0c2c042..d1d23ad3d6 100644
--- a/intern.h
+++ b/intern.h
@@ -528,6 +528,7 @@ void rb_str_associate(VALUE, VALUE);
 VALUE rb_str_associated(VALUE);
 void rb_str_setter(VALUE, ID, VALUE*);
 VALUE rb_str_intern(VALUE);
+VALUE rb_sym_to_s(VALUE);
 /* struct.c */
 VALUE rb_struct_new(VALUE, ...);
 VALUE rb_struct_define(const char*, ...);