root@vega:/tmp> cd php-4.2.3  
root@vega:/tmp/php-4.2.3> make
Making all in Zend
make[1]: Entering directory `/tmp/php-4.2.3/Zend'
/bin/sh ../libtool --silent --mode=compile gcc -DHAVE_CONFIG_H -I. -I. -I../main   -D_POSIX_PTHREAD_SEMANTICS -I../TSRM  -g -O2 -prefer-non-pic -static -c zend_language_parser.c
In file included from /usr/local/include/stdio.h:14,
                 from zend.h:35,
                 from zend_compile.h:24,
                 from zend_language_parser.c:148:
/usr/local/include/stdarg.h:43: parse error before `__gnuc_va_list'
/usr/local/include/stdarg.h:43: warning: data definition has no type or storage class
In file included from zend.h:35,
                 from zend_compile.h:24,
                 from zend_language_parser.c:148:
/usr/local/include/stdio.h:311: parse error before `__gnuc_va_list'
/usr/local/include/stdio.h:312: parse error before `__gnuc_va_list'
/usr/local/include/stdio.h:316: parse error before `__gnuc_va_list'
/usr/local/include/stdio.h:318: parse error before `__gnuc_va_list'
In file included from zend.h:59,
                 from zend_compile.h:24,
                 from zend_language_parser.c:148:
/usr/local/include/stdarg.h:90: parse error before `va_list'
/usr/local/include/stdarg.h:90: warning: data definition has no type or storage class
In file included from zend.h:180,
                 from zend_compile.h:24,
                 from zend_language_parser.c:148:
zend_hash.h:119: parse error before `va_list'
In file included from zend.h:181,
                 from zend_compile.h:24,
                 from zend_language_parser.c:148:
zend_llist.h:34: parse error before `va_list'
In file included from zend_compile.h:24,
                 from zend_language_parser.c:148:
zend.h:263: parse error before `va_list'
zend.h:394: parse error before `va_list'
make[1]: *** [zend_language_parser.lo] Error 1
make[1]: Leaving directory `/tmp/php-4.2.3/Zend'
make: *** [all-recursive] Error 1