%general-entities; ]> Grep temporary system When Cross Compiling the configure script does not determine the correct values for the following, Set the values manually: cat > config.cache << EOF ac_cv_func_malloc_0_nonnull=yes ac_cv_func_realloc_0_nonnull=yes EOF ./configure --prefix=/tools \ --build=${CLFS_HOST} --host=${CLFS_TARGET} \ --disable-perl-regexp --without-included-regex \ --cache-file=config.cache --disable-perl-regexp This ensures that the grep program does not get linked against a Perl Compatible Regular Expression (PCRE) library that may be present on the host but will not be available when building the final system.