-bash-3.00# ./configure --with-mysql --with-zlib
creating cache ./config.cache
checking for egrep... grep -E
checking for a sed that does not truncate output... /bin/sed
checking host system type... x86_64-unknown-linux-gnu
checking for gcc... gcc
checking whether the C compiler (gcc  ) works... yes
checking whether the C compiler (gcc  ) is a cross-compiler... no
checking whether we are using GNU C... yes
checking whether gcc accepts -g... yes
checking whether gcc and cc understand -c and -o together... yes
checking how to run the C preprocessor... gcc -E
checking for AIX... no
checking if compiler supports -R... no
checking if compiler supports -Wl,-rpath,... yes
checking for re2c... exit 0;
checking whether ln -s works... yes
checking for gawk... gawk
checking for bison... no
checking for byacc... no
configure: warning: You will need bison if you want to regenerate the                                                            PHP parsers.
checking for flex... lex
checking for yywrap in -ll... no
checking lex output file root... ./configure: line 2554: lex: command                                                            not found
configure: error: cannot find output from lex; giving up