Fix T44439: outliner's treestore could keep invalid ID pointers, could crash on undo due to invalid mem access.

We cannot nuke treestore in readfile's `blo_lib_link_screen_restore()`, because this will
destroy all UI-state data (like opened/closed items, etc.).

Since we cannot know for sure whether an ID pointer from tselem->id is valid here, we
have to ensure they are never invalid, i.e. to always set them to NULL when we delete them.

To do so, this commit uses a similar approach as what already exists for ID references
in WM notifiers - it extends `free_notifier_reference_cb()` to also nullify those IDs in
all outliners.

Note that some ID types are not used(shown) by outliner currently, so `TREESTORE_ID_TYPE` macro
was added, that checks whether an ID is possibly used by outliner. Avoids a few searches
in whole tree whene deleting some IDs.

Reviewers: campbellbarton, sergey

Maniphest Tasks: T44439

Differential Revision: https://developer.blender.org/D1272

1 files changed, 4 insertions, 0 deletions

diff --git a/source/blender/editors/space_outliner/outliner_intern.h b/source/blender/editors/space_outliner/outliner_intern.h
index b4b73a11a14..38672ef14dd 100644
--- a/source/blender/editors/space_outliner/outliner_intern.h
+++ b/source/blender/editors/space_outliner/outliner_intern.h
@@ -57,6 +57,10 @@ typedef struct TreeElement {
 	PointerRNA rnaptr;         // RNA Pointer
 }  TreeElement;
 
+#define TREESTORE_ID_TYPE(_id) \
+	(ELEM(GS((_id)->name), ID_SCE, ID_LI, ID_OB, ID_ME, ID_CU, ID_MB, ID_MA, ID_TE, ID_IM, ID_LT, ID_LA, ID_CA) || \
+	 ELEM(GS((_id)->name), ID_KE, ID_WO, ID_SPK, ID_GR, ID_AR, ID_AC, ID_BR, ID_PA, ID_GD, ID_LS))
+
 /* TreeElement->flag */
 #define TE_ACTIVE       1
 #define TE_ICONROW      2