Compiling Bro

I've tried to compile Bro on Linux version 2.2.12 with gcc (version
egcs-2.91.66 19990314/Linux (egcs-1.1.2 release)), but it didn't work. The
problem is, that the symbols from yacc/lex (yylhs, yylen, yydefred,
yydgoto,) are defined in libpcap and in Bro. I got the following errors:

Those are all yacc symbols. I suspect the problem is that your version
of yacc doesn't support the -p <sym prefix> flag. If not, then you'll
have to get one that does, such as GNU bison.