AIX 7.1 +...

The following experience, it took me a lot of time …..may help you.

1.Download PHP 5.2.14 (Other version NOT successed)

2.AIX 7.1 need  vi /include/gd_io.h , typedef struct gdIOCtx add void *data;  

3.Edit PHP Makefile add this
   PHP_CLI_OBJS = sapi/cli/php_cli.lo sapi/cli/php_http_parser.lo sapi/cli/php_cli_server.lo $(PHP_BINARY_OBJS)
PHP_CGI_OBJS = sapi/cgi/cgi_main.lo sapi/cgi/fastcgi.lo main/internal_functions.lo

4.Edit PHP sapi/apache2handler/php_functions.c (becouse we use Apache 2.4  NOT 2.2)
   –       AP_DECLARE_DATA extern unixd_config_rec unixd_config;
   +       AP_DECLARE_DATA extern unixd_config_rec ap_unixd_config;
   –       snprintf(tmp, sizeof(tmp), “%s(%d)/%d”, unixd_config.user_name, unixd_config.user_id, unixd_config.group_id);
   +       snprintf(tmp, sizeof(tmp), “%s(%d)/%d”, ap_unixd_config.user_name, ap_unixd_config.user_id, ap_unixd_config.group_id);

5.Link some file ….

   ls -s /opt/freeware/bin/pg_config /usr/bin/pg_config
   ls -s /opt/freeware/bin/mysql_config /usr/bin/mysql_config
   ln -s /opt/freeware/lib/libcrypto.so.0.9.8 /opt/freeware/lib/libcrypto.so    (OpenSSL ver cant greater than 0.9.8)

6.Configure PHP 5.2.14 with

./configure –prefix=/opt/freeware –with-apxs2=/opt/freeware/bin/apxs –with-zlib –with-zlib-dir=/opt/freeware –with-gd=/opt/freeware –with-freetype-dir=/opt/freeware –with-png-dir=/opt/freeware –with-mysql=/usr/local/mysql –with-mcrypt=/opt/freeware –enable-mbstring –with-gettext=/opt/freeware –with-libxml-dir=/opt/freeware/lib –enable-sockets –with-pcre-dir=/opt/freeware –with-snmp=/opt/freeware –with-openssl=/opt/freeware –with-bz2=/opt/freeware –with-jpeg-dir=/opt/freeware –enable-bcmath –enable-calendar –enable-maintainer-zts –disable-static –enable-shared –enable-ftp –with-curl=/opt/freeware –with-pdo-mysql=/usr/local/mysql –with-t1lib=/opt/freeware –with-libmbfl –with-iconv=/opt/freeware –with-iconv-dir=/opt/freeware –with-xpm-dir=/opt/freeware –enable-json –with-mysqli=/usr/local/mysql/bin/mysql_config –with-pgsql=/opt/freeware/bin/pg_config –with-pdo-pgsql=/opt/freeware/bin/pg_config

7.Make and Copy module
make
cp .libs/libphp5.so /xxx/xxx/apache/modules/  (xxx depend on your apache config)

Other note — Upgrading to 2.4 from 2.2
http://httpd.apache.org/docs/2.4/upgrading.html