netbsd build error (2)

[syzbot]

Hello,

syzbot found the following crash on:

HEAD commit: eb6711c3 Fix build, "pax" must be built before "libprop".
git tree: netbsd
console output: https://syzkaller.appspot.com/x/log.txt?x=117c793ca00000
dashboard link: https://syzkaller.appspot.com/bug?extid=ac76e240e283416b927d

Unfortunately, I don't have any reproducer for this crash yet.

IMPORTANT: if you fix the bug, please add the following tag to the commit:
Reported-by: syzbot+ac76e2...@syzkaller.appspotmail.com

/syzkaller/managers/netbsd/kernel/tools/libprop/../../common/lib/libprop/prop_dictionary.c:37:24:
fatal
error: sys/rbtree.h: No such file or directory

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[Maxime Villard]

#syz dup: netbsd build error