From aa268fc8ef84ec353f2ef0c3878d0ba8dcd54303 Mon Sep 17 00:00:00 2001
From: Behdad Esfahbod <behdad@behdad.org>
Date: Sun, 9 Mar 2025 03:31:01 -0600
Subject: [PATCH] [font/ft] See if tsan is happy with atomic_int_t serials

---
 src/hb-atomic.hh |  2 ++
 src/hb-font.cc   | 15 ++++++++++-----
 src/hb-font.hh   |  5 +++--
 src/hb-ft.cc     |  4 ++--
 4 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/src/hb-atomic.hh b/src/hb-atomic.hh
index 121c463a5..ce6ac38d8 100644
--- a/src/hb-atomic.hh
+++ b/src/hb-atomic.hh
@@ -186,6 +186,8 @@ struct hb_atomic_int_t
 
   hb_atomic_int_t& operator = (int v_) { set_relaxed (v_); return *this; }
   operator int () const { return get_relaxed (); }
+  int operator ++ (int) { return inc (); }
+  int operator -- (int) { return dec (); }
 
   void set_relaxed (int v_) { hb_atomic_int_impl_set_relaxed (&v, v_); }
   void set_release (int v_) { hb_atomic_int_impl_set (&v, v_); }
diff --git a/src/hb-font.cc b/src/hb-font.cc
index 2c79c0d83..526c96bbb 100644
--- a/src/hb-font.cc
+++ b/src/hb-font.cc
@@ -2744,7 +2744,8 @@ hb_font_set_variations (hb_font_t            *font,
   if (hb_object_is_immutable (font))
     return;
 
-  font->serial_coords = ++font->serial;
+  font->serial++;
+  font->serial_coords = font->serial;
 
   if (!variations_length && font->instance_index == HB_FONT_NO_VAR_NAMED_INSTANCE)
   {
@@ -2814,7 +2815,8 @@ hb_font_set_variation (hb_font_t *font,
   if (hb_object_is_immutable (font))
     return;
 
-  font->serial_coords = ++font->serial;
+  font->serial++;
+  font->serial_coords = font->serial;
 
   // TODO Share some of this code with set_variations()
 
@@ -2886,7 +2888,8 @@ hb_font_set_var_coords_design (hb_font_t    *font,
   if (hb_object_is_immutable (font))
     return;
 
-  font->serial_coords = ++font->serial;
+  font->serial++;
+  font->serial_coords = font->serial;
 
   int *normalized = coords_length ? (int *) hb_calloc (coords_length, sizeof (int)) : nullptr;
   float *design_coords = coords_length ? (float *) hb_calloc (coords_length, sizeof (float)) : nullptr;
@@ -2924,7 +2927,8 @@ hb_font_set_var_named_instance (hb_font_t *font,
   if (font->instance_index == instance_index)
     return;
 
-  font->serial_coords = ++font->serial;
+  font->serial++;
+  font->serial_coords = font->serial;
 
   font->instance_index = instance_index;
   hb_font_set_variations (font, nullptr, 0);
@@ -2971,7 +2975,8 @@ hb_font_set_var_coords_normalized (hb_font_t    *font,
   if (hb_object_is_immutable (font))
     return;
 
-  font->serial_coords = ++font->serial;
+  font->serial++;
+  font->serial_coords = font->serial;
 
   int *copy = coords_length ? (int *) hb_calloc (coords_length, sizeof (coords[0])) : nullptr;
   int *unmapped = coords_length ? (int *) hb_calloc (coords_length, sizeof (coords[0])) : nullptr;
diff --git a/src/hb-font.hh b/src/hb-font.hh
index 4c8190b0d..a8e6f7b0a 100644
--- a/src/hb-font.hh
+++ b/src/hb-font.hh
@@ -32,6 +32,7 @@
 #include "hb.hh"
 
 #include "hb-face.hh"
+#include "hb-atomic.hh"
 #include "hb-shaper.hh"
 
 
@@ -105,8 +106,8 @@ DECLARE_NULL_INSTANCE (hb_font_funcs_t);
 struct hb_font_t
 {
   hb_object_header_t header;
-  unsigned int serial;
-  unsigned int serial_coords;
+  hb_atomic_int_t serial;
+  hb_atomic_int_t serial_coords;
 
   hb_font_t *parent;
   hb_face_t *face;
diff --git a/src/hb-ft.cc b/src/hb-ft.cc
index f5fd7cae0..fdb021dd8 100644
--- a/src/hb-ft.cc
+++ b/src/hb-ft.cc
@@ -101,7 +101,7 @@ struct hb_ft_font_t
 
   mutable hb_mutex_t lock; /* Protects members below. */
   FT_Face ft_face;
-  mutable unsigned cached_serial;
+  mutable hb_atomic_int_t cached_serial;
   mutable hb_ft_advance_cache_t advance_cache;
 };
 
@@ -118,7 +118,7 @@ _hb_ft_font_create (FT_Face ft_face, bool symbol, bool unref)
 
   ft_font->load_flags = FT_LOAD_DEFAULT | FT_LOAD_NO_HINTING;
 
-  ft_font->cached_serial = (unsigned) -1;
+  ft_font->cached_serial = -1;
   new (&ft_font->advance_cache) hb_ft_advance_cache_t;
 
   return ft_font;