./bus_if.h:1:3: error: invalid preprocessing directive

From: bob prohaska <fbsd_at_www.zefox.net>
Date: Fri, 17 Jun 2022 14:58:54 UTC
Here's an example of a persistent buildkernel failure on a Pi3 tracking stable/13.
This particular failure has been persistent over the last couple weeks with new
builds attempted every few days. 

Logfiles are at
http://www.zefox.net/~fbsd/rpi3/crashes/20220617/

The initial error is

--- bhnd_pcie2_hostb.o ---
In file included from /usr/src/sys/dev/bhnd/cores/pcie2/bhnd_pcie2_hostb.c:59:
In file included from /usr/src/sys/sys/bus.h:764:
./bus_if.h:1:3: error: invalid preprocessing directive
# Meta data file /usr/obj/usr/src/arm64.aarch64/sys/GENERIC/modules/usr/src/sys/modules/bhnd/siba_bhndb/siba_bhndb.o.meta

That looks like the result of a stale file, but repeated updates
don't seem to clear it and the aftermath of the error is a flood of non-ascii
characters in the logfile, which I've not seen before during OS build attempts.

The build command is 
make -j2 -DWITh_META_MODE  buildworld > buildworld.log && make -j4 -DWITH_META_MODE  buildkernel   > buildkernel.log
which has been used for some months without visible difficulty. The use of filemon
has been continuous, generally without global cleans though I have used make clean
in selected subdirectories under /usr/src from time to time. 

An otherwise-similar Pi3 running -current exhibits no such behavior.

Thanks for reading, and any suggestions. 

bob prohaska