Mask is unable to properly feed forked processes

~# john
John the Ripper 1.8.0.16-jumbo-1-bleeding-4840892d68 2019-03-26 21:33:03 -0300 OMP [linux-gnu 64-bit x86_64 AVX2 AC]
Copyright (c) 1996-2019 by Solar Designer and others
Homepage: http://www.openwall.com/john/

command:
john --format=oldoffice-opencl --fork=8 --mask=?d?d?d?d?d?d?d?d xxoo.xls.hash

this version crack this hash:
xxooxxoo.file:$oldoffice$0b7663a051324739135c06ad1362bff35fb5a3178a5e8cfc7c19ebb9ff85f8ede*6b59b44de0ca2d58ccfbfa0138bebe50:::::xxoo.xls

response:
Using default input encoding: UTF-8
Loaded 1 password hash (oldoffice-opencl, MS Office <= 2003 [MD5/SHA1 RC4 OpenCL])
Cost 1 (hash type) is 0 for all loaded hashes
Node numbers 1-8 of 8 (fork)
1: Local worksize (LWS) 64, global worksize (GWS) 40960 (640 blocks)
Press 'q' or Ctrl-C to abort, almost any other key for status
5: Local worksize (LWS) 64, global worksize (GWS) 81920 (1280 blocks)
1: Warning: Only 2120 candidates left, minimum 40960 needed for performance.
1: OpenCL CL_OUT_OF_RESOURCES (-5) error in opencl_oldoffice_fmt_plug.c:522 - Failed transferring salt
6: Local worksize (LWS) 64, global worksize (GWS) 40960 (640 blocks)
8: Local worksize (LWS) 64, global worksize (GWS) 40960 (640 blocks)
3: Local worksize (LWS) 64, global worksize (GWS) 40960 (640 blocks)
4: Local worksize (LWS) 64, global worksize (GWS) 40960 (640 blocks)
7: Local worksize (LWS) 64, global worksize (GWS) 40960 (640 blocks)
root@gpu-server4:/usr/local/JohnTheRipper-bleeding-jumbo/run# 5: Warning: Only 43080 candidates left, minimum 81920 needed for performance.
5: OpenCL CL_OUT_OF_RESOURCES (-5) error in opencl_oldoffice_fmt_plug.c:522 - Failed transferring salt
6: Warning: Only 2120 candidates left, minimum 40960 needed for performance.
6: OpenCL CL_OUT_OF_RESOURCES (-5) error in opencl_oldoffice_fmt_plug.c:522 - Failed transferring salt
2: Local worksize (LWS) 64, global worksize (GWS) 40960 (640 blocks)
8: Warning: Only 2120 candidates left, minimum 40960 needed for performance.
3: Warning: Only 2120 candidates left, minimum 40960 needed for performance.
4: Warning: Only 2120 candidates left, minimum 40960 needed for performance.
7: Warning: Only 2120 candidates left, minimum 40960 needed for performance.
8: OpenCL CL_OUT_OF_RESOURCES (-5) error in opencl_oldoffice_fmt_plug.c:522 - Failed transferring salt
3: OpenCL CL_OUT_OF_RESOURCES (-5) error in opencl_oldoffice_fmt_plug.c:522 - Failed transferring salt
4: OpenCL CL_OUT_OF_RESOURCES (-5) error in opencl_oldoffice_fmt_plug.c:522 - Failed transferring salt
7: OpenCL CL_OUT_OF_RESOURCES (-5) error in opencl_oldoffice_fmt_plug.c:522 - Failed transferring salt

Start with the reported command using --format=oldoffice-opencl, --fork=8, and a mask, then inspect opencl_oldoffice_fmt_plug.c around line 522 where salt transfer fails. Reproduce the error on the reported Linux/OpenCL setup and trace how mask candidates are fed to forked processes. Done means the command no longer produces the reported OpenCL failure.