diff --git a/src/lib/ector/gl/ector_renderer_gl_base.eo b/src/lib/ector/gl/ector_renderer_gl_base.eo
index 0bbcd56a32..39c4789cb7 100644
--- a/src/lib/ector/gl/ector_renderer_gl_base.eo
+++ b/src/lib/ector/gl/ector_renderer_gl_base.eo
@@ -1,3 +1,5 @@
+type @extern GLshort: short; /* FIXME: We should not expose this in the API but probably redefine it. */
+
 abstract Ector.Renderer.GL.Base (Ector.Renderer.Generic.Base)
 {
    legacy_prefix: null;
@@ -5,7 +7,7 @@ abstract Ector.Renderer.GL.Base (Ector.Renderer.Generic.Base)
       fill {
          return: bool;
 	 params {
-	    @in flags: uint64_t;
+	    @in flags: uint64;
 	    @in vertex: GLshort*;
 	    @in vertex_count: uint;
 	    @in mul_col: uint;