Error while using apxs to compile ssl_ct module

[Ben.W]

I was trying to add SCTs for httpd's https connect. I did it step by step with the following, but still got error. Log is below.

root@vultr:/usr/local/src/httpd/modules/ssl# /usr/local/apache2/bin/apxs -ci -I /usr/local/ssl/include mod_ssl_ct.c ssl_ct_util.c ssl_ct_sct.c ssl_ct_log_config.c
/usr/local/apache2/build/libtool --silent --mode=compile gcc -std=gnu99 -prefer-pic   -DLINUX -D_REENTRANT -D_GNU_SOURCE -g -O2 -pthread -I/usr/local/apache2/include  -I/usr/local/apache2/include   -I/usr/local/ssl/include  -c -o mod_ssl_ct.lo mod_ssl_ct.c && touch mod_ssl_ct.slo
/usr/local/apache2/build/libtool --silent --mode=compile gcc -std=gnu99 -prefer-pic   -DLINUX -D_REENTRANT -D_GNU_SOURCE -g -O2 -pthread -I/usr/local/apache2/include  -I/usr/local/apache2/include   -I/usr/local/ssl/include  -c -o ssl_ct_util.lo ssl_ct_util.c && touch ssl_ct_util.slo
/usr/local/apache2/build/libtool --silent --mode=compile gcc -std=gnu99 -prefer-pic   -DLINUX -D_REENTRANT -D_GNU_SOURCE -g -O2 -pthread -I/usr/local/apache2/include  -I/usr/local/apache2/include   -I/usr/local/ssl/include  -c -o ssl_ct_sct.lo ssl_ct_sct.c && touch ssl_ct_sct.slo
In file included from mod_ssl.h:30:0,
                 from ssl_ct_sct.h:24,
                 from ssl_ct_sct.c:18:
mod_ssl.h:95:47: error: unknown type name 'ap_conf_vector_t'
                                               ap_conf_vector_t *,
                                               ^
/usr/local/apache2/include/apr_optional.h:51:42: note: in definition of macro 'APR_DECLARE_OPTIONAL_FN'
 typedef ret (APR_OPTIONAL_FN_TYPE(name)) args
                                          ^
apxs:Error: Command failed with rc=65536

It happened on both of Ubuntu 1404 and 1604, I really don't know how to fix this. Any ideas would be helpful, thanks!

[Ben Laurie]

I think this question is really for the Apache list, probably this
one: https://httpd.apache.org/lists.html#http-dev.

[Ben.W]

Thanks for the suggestion. I have sent an email to this list, hope it works :p