linux-4.14.y build error (2)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 5b7a52cd Linux 4.14.202
git tree: linux-4.14.y
console output: https://syzkaller.appspot.com/x/log.txt?x=17aba4d8500000
kernel config: https://syzkaller.appspot.com/x/.config?x=f2db3e6c4b1adcdc
dashboard link: https://syzkaller.appspot.com/bug?extid=dda72e73956f695f1b31
compiler: gcc (GCC) 10.1.0-syz 20200507

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+dda72e...@syzkaller.appspotmail.com

lib/string.c:259: undefined reference to `__ubsan_handle_nonnull_return_v1'

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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.