From 43e82682c58e354adc92cbbb0c95f721d019efab Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Wed, 5 Mar 2025 17:40:46 -0700
Subject: [PATCH] [cairo] Fix infinite loop in sweep-gradient code

Tested with U+F1314 from var font from:
https://github.com/googlefonts/color-fonts/blob/main/glyph_descriptions.md
---
 src/hb-cairo-utils.cc | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/hb-cairo-utils.cc b/src/hb-cairo-utils.cc
index ec1499e86..85c62d39a 100644
--- a/src/hb-cairo-utils.cc
+++ b/src/hb-cairo-utils.cc
@@ -726,6 +726,9 @@ _hb_cairo_add_sweep_gradient_patches (hb_color_stop_t *stops,
     float span;
 
     span = angles[n_stops - 1] - angles[0];
+    if (!span)
+      goto done;
+
     k = 0;
     if (angles[0] >= 0)
     {