BYacc: LALR(1) parser generator
1.9
Berkeley Yacc is an LALR(1) parser generator. Berkeley Yacc has been made as compatible as possible with AT&T Yacc. Berkeley Yacc can accept any input specification that conforms to the AT&T Yacc documentation. Specifications that take advantage of undocumented features of AT&T Yacc will probably be rejected.
ftp://ftp.cs.berkeley.edu/pub/4bsd
If you download the Setup version of the package, the dependencies, as listed below under Requirements, are already included, apart from msvcrt.dll. If you download the package as Zip files, then you must take care of the dependencies yourself.
General Installation Instructions