r279278 failed to build (yacc: maximum table size exceeded)

I have clean svn tree with base/head branch. I try to build world, but I
have some mysterious bugs. The latest is yacc failed to make c file on
phase 4.3:

===> usr.sbin/acpi/iasl (depend)
m4 -P
-I/usr/src/usr.sbin/acpi/iasl/../../../sys/contrib/dev/acpica/compiler
 /usr/src/usr.sbin/acpi/iasl/../../../sys/contrib/dev/acpica/compiler/aslparser.y
> aslcompiler.y
yacc -d -pAslCompiler -oaslcompilerparse.c aslcompiler.y
yacc: 89 shift/reduce conflicts.
yacc: f - maximum table size exceeded
*** Error code 2

/etc/make.conf is /dev/null.
I've also tried empty /etc/src.conf with no luck.

-- Eir Nym