--- mathmap-1.3.5/drawable.h	2009-08-23 13:56:14.000000000 +0200
+++ mathmap-1.3.5.new/drawable.h	2018-04-01 21:59:30.774269173 +0200
@@ -105,7 +105,7 @@ typedef struct _image_t
 	    mathmap_pools_t *pools;
 	    void *xy_vars;
 	    int num_args;
-	    userval_t args[];
+	    userval_t args[0];
 	} closure;
 	struct {
 	    float ax;