parse.y:2613
NODE*
rb_compile_file(f, file, start)
    const char *f;
    VALUE file;
    int start;
{
    lex_gets = rb_io_gets;
    lex_input = file;
    lex_pbeg = lex_p = lex_pend = 0;
    ruby_sourceline = start - 1;

    return yycompile(f, start);
}
