diff --git a/README.md b/README.md
index 729f74da..26ed1525 100644
--- a/README.md
+++ b/README.md
@@ -56,6 +56,8 @@ guide in the GLFW documentation.
  - [Cocoa] Bugfix: A superfluous I/O flag test prevented video modes from being
                    listed for Thunderbolt monitor
  - [Cocoa] Bugfix: Retrieving the name of some external displays caused segfault
+ - [Cocoa] Bugfix: The 10.9 SDK defines `GLintptrARB` and `GLsizeiptrARB`
+                   differently from the Khronos `glext.h`
  - [X11] Added setting of the `WM_CLASS` property to the initial window title
  - [X11] Bugfix: Removed joystick axis value negation left over from GLFW 2
  - [X11] Bugfix: The position of hidden windows was ignored by Metacity
diff --git a/deps/GL/glext.h b/deps/GL/glext.h
index 6cd79a20..acb46983 100644
--- a/deps/GL/glext.h
+++ b/deps/GL/glext.h
@@ -4130,8 +4130,13 @@ GLAPI void APIENTRY glVertexBlendARB (GLint count);
 
 #ifndef GL_ARB_vertex_buffer_object
 #define GL_ARB_vertex_buffer_object 1
+#if defined(__APPLE__)
+typedef long GLsizeiptrARB;
+typedef long GLintptrARB;
+#else
 typedef ptrdiff_t GLsizeiptrARB;
 typedef ptrdiff_t GLintptrARB;
+#endif
 #define GL_BUFFER_SIZE_ARB                0x8764
 #define GL_BUFFER_USAGE_ARB               0x8765
 #define GL_ARRAY_BUFFER_ARB               0x8892