ext/mmd/stack.c in rmultimarkdown-6.2.2.1 vs ext/mmd/stack.c in rmultimarkdown-6.4.0.1

@@ -85,11 +85,13 @@
 }
 
 
 /// Free the stack
 void stack_free(stack * s) {
-	free(s->element);
-	free(s);
+	if (s) {
+		free(s->element);
+		free(s);
+	}
 }
 
 
 /// Add a new pointer to the stack
 void stack_push(stack * s, void * element) {