From: Tim Ruffing <dev@real-or-random.org>
Date: Thu, 7 Nov 2024 02:09:09 +0000 (+0100)
Subject: Fix display of compositions when font style changes (Cairo backend)
X-Git-Url: http://git.eshelyaron.com/gitweb/?a=commitdiff_plain;h=acb5541b2b4e7283a0def27f30319bd67c696995;p=emacs.git

Fix display of compositions when font style changes (Cairo backend)

* src/ftcrfont.c (ftcrhbfont_end_hb_font): Don't persist the
result of 'cairo_ft_scaled_font_lock_face' in violation of the
API contract.  (Bug#73752)

(cherry picked from commit 9149aa89ee860627cc91e27c8659ad6f4efcfcd8)
---

diff --git a/src/ftcrfont.c b/src/ftcrfont.c
index 3700154e44a..ee111d18763 100644
--- a/src/ftcrfont.c
+++ b/src/ftcrfont.c
@@ -708,6 +708,13 @@ ftcrhbfont_end_hb_font (struct font *font, hb_font_t *hb_font)
   struct font_info *ftcrfont_info = (struct font_info *) font;
   cairo_scaled_font_t *scaled_font = ftcrfont_info->cr_scaled_font;
 
+  eassert (hb_font == ftcrfont_info->hb_font);
+  /* ftcrfont_info->hb_font holds a reference to the FT_Face returned by
+     cairo_ft_scaled_font_lock_face. Keeping it around after the
+     matching unlock call would violate the API contract (Bug#73752). */
+  hb_font_destroy (ftcrfont_info->hb_font);
+  ftcrfont_info->hb_font = NULL;
+
   cairo_ft_scaled_font_unlock_face (scaled_font);
   ftcrfont_info->ft_size = NULL;
 }