diff --git a/app/operations/layer-modes/gimpoperationerase.c b/app/operations/layer-modes/gimpoperationerase.c
index 729d6366f0..1cc1ba8597 100644
--- a/app/operations/layer-modes/gimpoperationerase.c
+++ b/app/operations/layer-modes/gimpoperationerase.c
@@ -119,6 +119,7 @@ gimp_operation_erase_process (GeglOperation       *op,
       break;
 
     case GIMP_LAYER_COMPOSITE_SRC_ATOP:
+    case GIMP_LAYER_COMPOSITE_AUTO:
       while (samples--)
         {
           gfloat layer_alpha;
diff --git a/app/operations/layer-modes/gimpoperationlayermode.c b/app/operations/layer-modes/gimpoperationlayermode.c
index f83f2a0ef3..73e54b7d59 100644
--- a/app/operations/layer-modes/gimpoperationlayermode.c
+++ b/app/operations/layer-modes/gimpoperationlayermode.c
@@ -2013,6 +2013,7 @@ gimp_layer_mode_get_blend_fun (GimpLayerMode mode)
     case GIMP_LAYER_MODE_ERASE:
     case GIMP_LAYER_MODE_REPLACE:
     case GIMP_LAYER_MODE_ANTI_ERASE:
+    case GIMP_LAYER_MODE_SEPARATOR: /* to stop GCC from complaining :P */
       return blendfun_dummy;
     }