Ungroup in Node editor crash Blender
Open, ConfirmedPublic

Description

System Information
W10 64b

Blender Version
7c75c2d

Short description of error
Blender crash everytime I want to ungroup shader

Exact steps for others to reproduce the error

  1. open
  2. select cube
  3. ungroup shader in "kamuflaz texture" group
  4. crash

Details

Type
Bug
Philipp Oeser (lichtwerk) triaged this task as Confirmed priority.Wed, Jun 13, 9:45 AM

Can confirm, crash in master, worked in 2.79b, having a closer look now

bisected down to rB1cddab18ded9

1  action_groups_clear_tempflags     action.c             392   0x251694e 
2  action_move_fcurves_by_basepath   anim_sys.c           442   0x251bac3 
3  BKE_animdata_separate_by_basepath anim_sys.c           546   0x251be34 
4  node_group_ungroup                node_group.c         263   0x19133ab 
5  node_group_ungroup_exec           node_group.c         368   0x191376e

in rB1cddab18ded9 BKE_id_copy_ex changed to not NULLify r_newid anymore (returning early out when source is NULL)

So when this happens with NULL action, the returned action is not NULL anymore (but garbage pointer created in BKE_action_copy), leading to problems later...

P726 is quick fix (but not sure returnpointer should always be NULL when source is NULL? or check LIB_ID_CREATE_NO_ALLOCATE as well?)

@Sergey Sharybin (sergey): mind having a look?