php version :
install step:
$sudo pecl update-channels
Output:
$sudo pecl install intl
Output:
cc -I/Applications/XAMPP/xamppfiles/include -Wno-write-strings -I. -I/private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/pear/temp/intl -DPHP_ATOM_INC -I/private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/pear/temp/pear-build-rootk5lReQ/intl-3.0.0/include -I/private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/pear/temp/pear-build-rootk5lReQ/intl-3.0.0/main -I/private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/pear/temp/intl -I/Applications/XAMPP/xamppfiles/include/php -I/Applications/XAMPP/xamppfiles/include/php/main -I/Applications/XAMPP/xamppfiles/include/php/TSRM -I/Applications/XAMPP/xamppfiles/include/php/Zend -I/Applications/XAMPP/xamppfiles/include/php/ext -I/Applications/XAMPP/xamppfiles/include/php/ext/date/lib -I/Applications/XAMPP/xamppfiles/include -DHAVE_CONFIG_H -g -O2 -c /private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/pear/temp/intl/php_intl.c -fno-common -DPIC -o .libs/php_intl.o
In file included from /private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/pear/temp/intl/php_intl.c:25:
In file included from /private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/pear/temp/intl/php_intl.h:34:
/private/var/folders/zz/zyxvpxvq6csfxvn_n0000000000000/T/pear/temp/intl/intl_error.h:24:10: fatal error: 'ext/standard/php_smart_str.h' file not found
#include <ext/standard/php_smart_str.h>
^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
1 error generated.
make: *** [php_intl.lo] Error 1
