[glib] README.in: Note undefined behavior with new g_type_init() -> ctor change

[Colin Walters <walters src gnome org>]

commit d04ac162c10f3a855dbbaea6efe06de9d85aea02
Author: Colin Walters <walters verbum org>
Date:   Sat Oct 27 12:28:14 2012 -0400

    README.in: Note undefined behavior with new g_type_init() -> ctor change
    
    https://bugzilla.gnome.org/show_bug.cgi?id=686822

 README.in |    5 ++++-
 1 files changed, 4 insertions(+), 1 deletions(-)
---
diff --git a/README.in b/README.in
index b637e9e..71b789a 100644
--- a/README.in
+++ b/README.in
@@ -70,7 +70,10 @@ Patches should be in unified diff form. (The -up option to GNU diff.)
 Notes about GLib 2.36
 =====================
 
-* It is no longer necessary to call g_type_init()
+* It is no longer necessary to call g_type_init().  If you are
+  loading GLib as a dynamic module, you should be careful to avoid
+  unloading it, then subsequently loading it again.  This never
+  really worked before, but it is now explicitly undefined behavior.
 
 Notes about GLib 2.34
 =====================