Update header
diff --git a/api/GL/glext.h b/api/GL/glext.h
index ab0870b..6edf472 100644
--- a/api/GL/glext.h
+++ b/api/GL/glext.h
@@ -51,7 +51,7 @@
 #define GLAPI extern
 #endif
 
-#define GL_GLEXT_VERSION 20170817
+#define GL_GLEXT_VERSION 20170823
 
 /* Generated C header for:
  * API: gl
@@ -5704,6 +5704,10 @@
 #define GL_AMD_shader_explicit_vertex_parameter 1
 #endif /* GL_AMD_shader_explicit_vertex_parameter */
 
+#ifndef GL_AMD_shader_image_load_store_lod
+#define GL_AMD_shader_image_load_store_lod 1
+#endif /* GL_AMD_shader_image_load_store_lod */
+
 #ifndef GL_AMD_shader_stencil_export
 #define GL_AMD_shader_stencil_export 1
 #endif /* GL_AMD_shader_stencil_export */