From 1a51f71afd794a52a24cbcb7547000e0c563b0f6 Mon Sep 17 00:00:00 2001
From: Garret Rieger <grieger@google.com>
Date: Mon, 19 Dec 2022 22:40:11 +0000
Subject: [PATCH] [subset] don't segfault when --help-all is specified w/
 instancing options.

---
 util/hb-subset.cc | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/util/hb-subset.cc b/util/hb-subset.cc
index bd4dea2d3..2f90048bd 100644
--- a/util/hb-subset.cc
+++ b/util/hb-subset.cc
@@ -668,6 +668,10 @@ parse_instance (const char *name,
 		GError    **error)
 {
   subset_main_t *subset_main = (subset_main_t *) data;
+  if (!subset_main->face) {
+    // There is no face, which is needed to set up instancing. Skip parsing these options.
+    return true;
+  }
 
   char *s = strtok((char *) arg, "=");
   while (s)