Actually we don't need any special YACC'ing here. The ones known to

Bmake are fine.

gnu/usr.bin/cc/tradcpp0/Makefile

@@ -5,18 +5,11 @@
 .PATH: ${GCCDIR}
 
 PROG=	tradcpp0
-SRCS=	tradcpp.c tradcif.c
+SRCS=	tradcpp.c tradcif.y
 BINDIR=	/usr/libexec
 NOMAN=	1
 
 DPADD+=	${LIBCC_INT}
 LDADD+=	${LIBCC_INT}
 
-#	${YACC} ${GCCDIR}/tradcif.y
-tradcif.c: tradcif.y
-	${YACC} ${.ALLSRC}
-	sed -e "s/malloc/xmalloc/g" \
-	    -e "s/realloc/xrealloc/g" \
-	    y.tab.c >${.TARGET}
-
 .include <bsd.prog.mk>