Grep-2.5.1 lacks description of its configure options

[lizardo@…]

Grep-2.5.1 installation page on Chapter 5 is lacking descriptions for "--with-included-regex" and "--disable-perl-regexp" configure options. From the pure_lfs.txt hint: The "--with-included-regex" is needed so that all tests pass. Without this switch the regex code from glibc is used and as of glibc-2.3.1 that code is known to be a bit buggy. From LFS-BOOK 4.1: --disable-perl-regexp: This configure option makes sure grep is not linked against the PCRE library, which is often only available as a shared library in distributions. Not using this option might result in a compilation error.