diff --git a/src/vim9compile.c b/src/vim9compile.c
index 38edbab..9f36dc9 100644
--- a/src/vim9compile.c
+++ b/src/vim9compile.c
@@ -3339,7 +3339,9 @@
 	    case CMD_echowindow:
 		    {
 			long cmd_count = get_cmd_count(line, &ea);
-			if (cmd_count >= 0)
+			if (cmd_count < 0)
+			    line = NULL;
+			else
 			    line = compile_mult_expr(p, ea.cmdidx,
 							     cmd_count, &cctx);
 		    }