diff --git a/code/nel/src/3d/driver/opengl/GL/glext.h b/code/nel/src/3d/driver/opengl/GL/glext.h
index b5eee6503..0021d6b1e 100644
--- a/code/nel/src/3d/driver/opengl/GL/glext.h
+++ b/code/nel/src/3d/driver/opengl/GL/glext.h
@@ -4657,8 +4657,13 @@ GLAPI void APIENTRY glVertexBlendARB (GLint count);
 
 #ifndef GL_ARB_vertex_buffer_object
 #define GL_ARB_vertex_buffer_object 1
+#if defined(__APPLE__)
+typedef intptr_t GLsizeiptrARB;
+typedef intptr_t 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