This seems like a symptom of the same problem reported
in #7392. A megapatch posted under the subject
"[PHP-DEV] Resources patch", on Thu 10/19/00 11:58 PM,
seems to be the culprit. A number of other extensions
may (or may not) also be affected.

gd.c: In function `php_minit_gd':
gd.c:234: warning: passing arg 1 of `zend_register_list_destructors_ex' from incompatible pointer type
gd.c:235: warning: passing arg 1 of `zend_register_list_destructors_ex' from incompatible pointer type
gd.c: At top level:
gd.c:2077: conflicting types for `php_free_ps_font'
gdt1.h:26: previous declaration of `php_free_ps_font'
gd.c:2084: conflicting types for `php_free_ps_enc'
gdt1.h:27: previous declaration of `php_free_ps_enc'
make[3]: *** [gd.lo] Error 1
make[3]: Leaving directory `/usr/src/php4-200010221745/ext/gd'
make[2]: *** [all-recursive] Error 1
make[2]: Leaving directory `/usr/src/php4-200010221745/ext/gd'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/usr/src/php4-200010221745/ext'
make: *** [all-recursive] Error 1