[Bf-blender-cvs] [995c904d00e] master: Fix (unreported) crash in liboverride code on rare cases.

[Bastien Montagne]

Commit: 995c904d00e1e0713a1549ca16b2775a9dcdd281
Author: Bastien Montagne
Date:   Mon Jul 11 19:04:24 2022 +0200
Branches: master
https://developer.blender.org/rB995c904d00e1e0713a1549ca16b2775a9dcdd281

Fix (unreported) crash in liboverride code on rare cases.

When dealing with 'embedded' IDs (and the like, e.g. shape keys),
liboverride code could fail in case the reference linked data (e.g. a
mesh) would not have a shapekey anymore, while the override mesh would
still have one.

Found while investigating another issue in Heist production file
`Heist/pro/animation_test/einar/einar_new_expression_shapes2.blend`,
r1230.

===================================================================

M	source/blender/blenkernel/intern/lib_override.cc

===================================================================

diff --git a/source/blender/blenkernel/intern/lib_override.cc b/source/blender/blenkernel/intern/lib_override.cc
index d816b5ede5f..cdea97b6c6a 100644
--- a/source/blender/blenkernel/intern/lib_override.cc
+++ b/source/blender/blenkernel/intern/lib_override.cc
@@ -1771,6 +1771,11 @@ static bool lib_override_library_resync(Main *bmain,
               break;
           }
         }
+        if (reference_id == nullptr) {
+          /* Can happen e.g. when there is a local override of a shapekey, but the matching linked
+           * obdata (mesh etc.) does not have any shapekey anymore. */
+          continue;
+        }
         BLI_assert(GS(reference_id->name) == GS(id->name));
 
         if (!BLI_ghash_haskey(linkedref_to_old_override, reference_id)) {