[HarfBuzz] harfbuzz: Branch 'master'

[Behdad Esfahbod]

 src/hb-shaper-private.hh |    5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

New commits:
commit 69fd6e157c7ec83a5d5d8731fc14675ce4509b09
Author: Behdad Esfahbod <behdad at behdad.org>
Date:   Thu Jan 10 00:03:36 2013 -0600

    Fix crasher during multi-thread shaper data creation
    
    Sample crash:
    
    0  _hb_graphite2_shaper_face_data_destroy (data=0xffffffffffffffff)
        at ../../src/hb-graphite2.cc:129
    1  0x00007ffff4271d7d in hb_graphite2_shaper_face_data_ensure (
        face=<optimized out>) at ../../src/hb-shaper-list.hh:35
    2  hb_shape_plan_plan (shaper_list=<optimized out>, num_user_features=0,
        user_features=0x0, shape_plan=0xf7b490) at ../../src/hb-shaper-list.hh:35
    3  hb_shape_plan_create (face=<optimized out>, props=<optimized out>,
        user_features=0x0, num_user_features=0, shaper_list=<optimized out>)
        at ../../src/hb-shape-plan.cc:108
    4  0x00007ffff4272c93 in hb_shape_plan_create_cached (face=0x10cf2b0,
        props=0x11980d8, user_features=0x0, num_user_features=<optimized out>,
        shaper_list=0x0) at ../../src/hb-shape-plan.cc:283

diff --git a/src/hb-shaper-private.hh b/src/hb-shaper-private.hh
index 9d30c1e..29c4493 100644
--- a/src/hb-shaper-private.hh
+++ b/src/hb-shaper-private.hh
@@ -95,7 +95,10 @@ hb_##shaper##_shaper_##object##_data_ensure (hb_##object##_t *object) \
     if (unlikely (!data)) \
       data = (HB_SHAPER_DATA_TYPE (shaper, object) *) HB_SHAPER_DATA_INVALID; \
     if (!hb_atomic_ptr_cmpexch (&HB_SHAPER_DATA (shaper, object), NULL, data)) { \
-      HB_SHAPER_DATA_DESTROY_FUNC (shaper, object) (data); \
+      if (data && \
+	  data != HB_SHAPER_DATA_INVALID && \
+	  data != HB_SHAPER_DATA_SUCCEEDED) \
+	HB_SHAPER_DATA_DESTROY_FUNC (shaper, object) (data); \
       goto retry; \
     } \
   } \