diff --git a/src/httpd.c b/src/httpd.c
index de29ad25..7af33a27 100644
--- a/src/httpd.c
+++ b/src/httpd.c
@@ -1091,7 +1091,7 @@ httpd_fixup_uri(struct evhttp_request *req)
return fixed;
}
-static char *http_reply_401 = "401 UnauthorizedAuthorization required";
+static const char *http_reply_401 = "401 UnauthorizedAuthorization required";
int
httpd_basic_auth(struct evhttp_request *req, char *user, char *passwd, char *realm)