buildworld fails on nslexr.c?

cc -O -pipe -march=pentium4 -I/usr/src/lib/libc/include 
-I/usr/src/lib/libc/../../include -I/usr/src/lib/libc/i386 
-D__DBINTERFACE_PRIVATE -I/usr/src/lib/libc/../../contrib/gdtoa -DINET6 
-I/usr/obj/usr/src/lib/libc -DPOSIX_MISTAKE -I/usr/src/lib/libc/locale 
-DBROKEN_DES -DPORTMAP -DDES_BUILTIN -I/usr/src/lib/libc/rpc -DYP 
-DHESIOD -Wsystem-headers -Werror -Wall -Wno-format-y2k 
-Wno-uninitialized -c nslexer.c
/dev/stdout: In function `_nsyylex':
/dev/stdout:711: warning: label `find_rule' defined but not used
/usr/src/lib/libc/net/nslexer.l: At top level:
/dev/stdout:1678: warning: `yy_flex_realloc' defined but not used