diff --git a/gtk.cabal b/gtk.cabal
--- a/gtk.cabal
+++ b/gtk.cabal
@@ -1,5 +1,5 @@
 Name:           gtk
-Version:        0.15.2
+Version:        0.15.3
 License:        LGPL-2.1
 License-file:   COPYING
 Copyright:      (c) 2001-2010 The Gtk2Hs Team
@@ -135,7 +135,7 @@
 
 custom-setup
   setup-depends: base >= 4.6,
-                 Cabal >= 1.24 && < 2.5,
+                 Cabal >= 1.24 && < 3.1,
                  gtk2hs-buildtools >= 0.13.2.0 && < 0.14
 
 Library
@@ -381,9 +381,9 @@
         -- needs to be imported from this module:
         x-Signals-Import: Graphics.UI.Gtk.General.Threading
         include-dirs:   .
-        cpp-options: -U__BLOCKS__
+        cpp-options: -U__BLOCKS__ -D__attribute__(A)=
         if os(darwin) || os(freebsd)
-          cpp-options: -D__attribute__(A)= -D_Nullable= -D_Nonnull=
+          cpp-options: -D_Nullable= -D_Nonnull=
         if !flag(deprecated)
           cpp-options:  -DDISABLE_DEPRECATED
         else