ID 239752 - Rendering two ZDefocus nodes crashes with double free / malloc_error (Linux)

Problem summary
Rendering two ZDefocus nodes crashes with double free / malloc_error

Customer reported version
nuke.10.0v3

Customer reported platform
suse

Steps to reproduce

Use script and 5 input exr's found at

\\netpics\netpics\Testing\Bugs\239752

1.
open script in NukeX and set the Read and Write file knobs

2.
save a copy of the script

3.

render from command line

Nuke10.0v4 -x -F 101-105 <script>

Workaround
Unknown.

Reproduced by support
Nuke10.0v4

OS 10.10.5

Expected behaviour
render 5 exr's without crashing

Actual behaviour
on linux, for customer:

*** Error in `/u/soft/foundry/nuke10.0v3/Nuke10.0': double free or corruption (out): 0x00007ff46c45bdc0 ***

on OSX for Support:

Nuke10.0v4(913,0x11e001000) malloc: *** error for object 0x110abc200: double free