Hello Gentoo,
I've recently started with Gentoo in the last few months, still interested in learning about the build system and to start trying to slim down my install. This morning I ran into the following issue, I'll try to provide as much detail as I can:

THE ISSUE:
I am failing to emerge sys-kernel/gentoo-kernel-5.4.105 with a sandbox violation. The violation summary is inserted below:

* --------------------------- ACCESS VIOLATION SUMMARY ---------------------------
* LOG FILE: "/var/tmp/portage/sys-kernel/gentoo-kernel-5.4.105/temp/sandbox.log"
*
VERSION 1.0
FORMAT: F - Function called
FORMAT: S - Access Status
FORMAT: P - Path as passed to function
FORMAT: A - Absolute Path (not canonical)
FORMAT: R - Canonical Path
FORMAT: C - Command Line

F: unlink
S: deny
P: /dev/null.dwo
A: /dev/null.dwo
R: /dev/null.dwo
C: x86_64-pc-linux-gnu-gcc -Werror -gsplit-dwarf -S -x c /dev/null -o /dev/null
* --------------------------------------------------------------------------------

The relevant section of the log is:
x86_64-pc-linux-gnu-gcc -Wl,-O1 -Wl,--as-needed -o scripts/kconfig/conf scripts/kconfig/conf.o scripts/kconfig/confdata.o scripts/kconfig/expr.o scripts/kconfig/lexer.lex.o scripts/kconfig/parser.tab.o scripts/kconfig/preprocess.o scripts/kconfig/symbol.o
scripts/kconfig/conf --olddefconfig Kconfig
* ACCESS DENIED: unlink: /dev/null.dwo
#
# configuration written to .config
#
make[1]: Leaving directory '/var/tmp/portage/sys-kernel/gentoo-kernel-5.4.105/work/modprep'

I am trying to use a custom config file and am building gentoo-kernel with the "savedconfig" USE flag. I also recently updated to Portage 3.0.17.

TROUBLESHOOTING STEPS:
To try to troubleshoot, I have ran "eclean distfiles" and have removed the "/var/tmp/portage/sys-kernel/gentoo-kernel-5.4.105" directory. I then ran a sync and deep update, but the issue remains.

I have attached the log generated by portage. Let me know if there is any other info that would be helpful.

Any help would be greatly appreciated,
Grant