diff --git a/src/version.c b/src/version.c
index 8be8b38..953bb22 100644
--- a/src/version.c
+++ b/src/version.c
@@ -700,6 +700,8 @@
 static int included_patches[] =
 {   /* Add new patch number below this line */
 /**/
+    684,
+/**/
     683,
 /**/
     682,
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);
 		    }
diff --git a/src/vim9instr.c b/src/vim9instr.c
index 4407d59..9c3b2a9 100644
--- a/src/vim9instr.c
+++ b/src/vim9instr.c
@@ -1876,6 +1876,7 @@
 {
     isn_T	*isn;
 
+    RETURN_OK_IF_SKIP(cctx);
     if ((isn = generate_instr_drop(cctx, isn_type, count)) == NULL)
 	return FAIL;
     isn->isn_arg.number = count;