Got chokes when updating to different commits in the FreeBSD
repository.

Here's a reproducer:

$ got clone ssh://anongit@git.freebsd.org/src.git
$ got co -c 67bceb38f463d8a929c55efdcfcfefc9aedfeff6 src.git
$ cd src
$ got up
[...]
U  contrib/llvm-project/libcxx/include/__split_buffer
D  contrib/llvm-project/libcxx/include/__sso_allocator
U  contrib/llvm-project/libcxx/include/__std_stream
U  contrib/llvm-project/libcxx/include/__string
got: stat: /home/naddy/tmp/src/contrib/llvm-project/libcxx/include/__string/char_traits.h: Not a directory

I thought I could bisect this to a particular commit, but promptly
ran into the next problem:

$ got up -c 67bceb38f463d8a929c55efdcfcfefc9aedfeff6    # back to start
[...]
$ got up -c e98f952c82907ec39cebb4e66efd92691c835e05
[...]
U  usr.sbin/yppoll/Makefile
U  usr.sbin/yppush/Makefile
U  usr.sbin/ypserv/Makefile
U  usr.sbin/ypset/Makefile
Updated to refs/heads/main: e98f952c82907ec39cebb4e66efd92691c835e05
File paths obstructed by a non-regular file: 2

I then tried to bisect that, but arrived at e98f952c8290 without
problem.  However, I then couldn't get back to 67bceb38f463.

The error paths I've seen all involve llvm or openzfs, so vendor
branches and merge commits are likely part of the problem.

-- 
Christian "naddy" Weisgerber                          naddy@mips.inka.de