# Compiling Bro
**URL:** https://community.zeek.org/t/compiling-bro/68
**Category:** Zeek
**Created:** [November 18, 1999, 1:04pm UTC](https://community.zeek.org/t/compiling-bro/68 "1999-11-18T13:04:30Z")
**Posts on this page:** 2
**Page:** 1
### Author:  [@hir](https://community.zeek.org/u/hir)
#### Post date: [November 18, 1999, 1:04pm UTC](https://community.zeek.org/t/compiling-bro/68/1 "1999-11-18T13:04:30Z")
Hallo all!
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:
../libpcap-0.4/libpcap.a(grammar.o)(.data+0x3c): multiple definition of
`yylhs'
parse.o(.data+0x40): first defined here
/usr/i486-linux/bin/ld: Warning: size of symbol `yylhs' changed from 272 to
204 in grammar.o
../libpcap-0.4/libpcap.a(grammar.o)(.data+0x108): multiple definition of
`yylen'
parse.o(.data+0x160): first defined here
/usr/i486-linux/bin/ld: Warning: size of symbol `yylen' changed from 272 to
204 in grammar.o
../libpcap-0.4/libpcap.a(grammar.o)(.data+0x1d4): multiple definition of
`yydefred'
parse.o(.data+0x280): first defined here
/usr/i486-linux/bin/ld: Warning: size of symbol `yydefred' changed from 588
to 300 in grammar.o
My Questions: Why does libpcap export this symbols? Why does nobody but me
has this problem and what can I do to solve it?
Hartmut Irrgang
---
### Author:  [@system](https://community.zeek.org/u/system)
#### Post date: [May 6, 2022, 3:36pm UTC](https://community.zeek.org/t/compiling-bro/68/2 "2022-05-06T15:36:08Z")