Problems using bison and flex with C++

[Carlos Augusto Lains Leitão]

Hi,

        My name is Carlos and i am experiencing some problems using flex and 
bison with c++. I have generated the lexical scanner with flex and the the 
parser with bison. When i compile my program with gcc there is no problem and 
everything goes well but when i use g++ to compile the compiler points some 
errors such like: "undefined reference to yylex in the parser.tab.c generated 
by bison, undefined reference to yyparse in lex.yy.c generated by flex, 
undefined reference to yyerror in parser.tab.c generated by bison". Colud 
anyone give me an advice.

Thanks in advance,

                Carlos Augusto