diff --git a/wt-status.c b/wt-status.c
index 08d40d202e..05b69dc4d3 100644
--- a/wt-status.c
+++ b/wt-status.c
@@ -729,7 +729,6 @@ static void wt_status_print_submodule_summary(struct wt_status *s, int uncommitt
 	struct strbuf cmd_stdout = STRBUF_INIT;
 	struct strbuf summary = STRBUF_INIT;
 	char *summary_content;
-	size_t len;
 
 	argv_array_pushf(&sm_summary.env_array, "GIT_INDEX_FILE=%s",
 			 s->index_file);
@@ -749,10 +748,10 @@ static void wt_status_print_submodule_summary(struct wt_status *s, int uncommitt
 
 	run_command(&sm_summary);
 
-	len = strbuf_read(&cmd_stdout, sm_summary.out, 1024);
+	strbuf_read(&cmd_stdout, sm_summary.out, 1024);
 
 	/* prepend header, only if there's an actual output */
-	if (len) {
+	if (cmd_stdout.len) {
 		if (uncommitted)
 			strbuf_addstr(&summary, _("Submodules changed but not updated:"));
 		else
@@ -763,6 +762,7 @@ static void wt_status_print_submodule_summary(struct wt_status *s, int uncommitt
 	strbuf_release(&cmd_stdout);
 
 	if (s->display_comment_prefix) {
+		size_t len;
 		summary_content = strbuf_detach(&summary, &len);
 		strbuf_add_commented_lines(&summary, summary_content, len);
 		free(summary_content);