I recently tried to build a kernel with COMPAT_AOUT but not COMPAT_13.
Everything went fine right up until the link step....

ld -Ttext F0004000 -e start -n -X -o netbsd ${SYSTEM_OBJ} vers.o
aout_sysent.o(.data+0x33c): undefined reference to `compat_13_sys_sigreturn'
*** Error code 1

Stop.

This was with a 1999-08-13 source tree; has it been fixed since?  It
appears on cursory inspection to be due to compat_13_machdep.c being
pulled in only when COMPAT_13, but all the other compatability routines
referred to in aout_sysent being in libcompat and hence available to be
linked in regardless of COMPAT_ options.

It was on a SPARC, but I'm sending to tech-kern because the cause
doesn't *look* SPARC-specific.

For now I'm going to just turn on COMPAT_13 as well.  (The idea was for
this kernel to be minimalist, as small as feasible, but to avoid
recompiling lots of userland I couldn't afford to skip COMPAT_AOUT.)

					der Mouse

			       mouse@rodents.montreal.qc.ca
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