Description:
------------
With v5.6, ./configure output suggests that OpenSSL won't be supported in cURL, while GnuTLS is expected to be supported in cURL. This is actually not the case after the build, and in fact I would expect OpenSSL to *be* supported while I didn't include GnuTLS.

However, it seems ok with v7.2.

In both cases, here is the output from "curl -V":
curl -V
curl 7.58.0 (x86_64-pc-linux-gnu) libcurl/7.58.0 OpenSSL/1.0.2n zlib/1.2.11 libidn2/0.10 libpsl/0.12.0 (+libicu/55.1) libssh2/1.8.0 nghttp2/1.30.0 librtmp/2.3
Release-Date: 2018-01-24
Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps pop3 pop3s rtmp rtsp scp sftp smb smbs smtp smtps telnet tftp
Features: AsynchDNS IDN IPv6 Largefile GSS-API Kerberos SPNEGO NTLM NTLM_WB SSL libz TLS-SRP HTTP2 UnixSockets HTTPS-proxy Metalink PSL

Test script:
---------------
cd /usr/local/src/php-5.6.33
rm -R ext/amqp 2>/dev/null ; mkdir ext/amqp ; cp -R ../amqp-1.9.3/* ext/amqp/
rm -R ext/geoip 2>/dev/null ; mkdir ext/geoip ; cp -R ../geoip-1.1.1/* ext/geoip/
rm -R ext/http 2>/dev/null ; mkdir ext/http ; cp -R ../pecl_http-2.6.0/* ext/http/
rm -R ext/igbinary 2>/dev/null ; mkdir ext/igbinary ; cp -R ../igbinary-1.2.1/* ext/igbinary/
rm -R ext/redis 2>/dev/null ; mkdir ext/redis ; cp -R ../redis-3.1.2/* ext/redis/
rm -R ext/raphf 2>/dev/null ; mkdir ext/raphf ; cp -R ../raphf-1.1.2/* ext/raphf/
rm -R ext/propro 2>/dev/null ; mkdir ext/propro ; cp -R ../propro-1.0.2/* ext/propro/
rm -R ext/imagick 2>/dev/null ; mkdir ext/imagick ; cp -R ../imagick-3.4.3/* ext/imagick/
rm -R ext/timezonedb 2>/dev/null ; mkdir ext/timezonedb ; cp -R ../timezonedb-2017.3/* ext/timezonedb/
rm -R ext/ssh2 2>/dev/null ; mkdir ext/ssh2 ; cp -R ../ssh2-0.13/* ext/ssh2/
rm -R ext/xdiff 2>/dev/null ; mkdir ext/xdiff ; cp -R ../xdiff-1.5.2/* ext/xdiff/
rm -R ext/libsodium 2>/dev/null ; mkdir ext/libsodium ; cp -R ../libsodium-php-1.0.7/* ext/libsodium/
cd /usr/local/src/php-5.6.33
rm configure 2>/dev/null ; ./buildconf --force ; make clean
./configure --prefix=/usr/local/php56 --disable-all --with-apxs2=/usr/local/apache2/bin/apxs --with-iconv=/usr/local/lib --with-icu-dir=/usr/local --enable-libxml --enable-xml --enable-dom --enable-ctype --with-curl=/usr/local --enable-json --enable-session --enable-simplexml --with-sqlite3 --enable-pdo --with-pdo-mysql --with-pdo-sqlite --with-zlib=/usr/local --with-openssl --enable-soap --enable-bcmath --with-bz2 --enable-calendar --enable-exif --enable-ftp --with-gd --with-gettext --with-libxml-dir --enable-mbstring --with-mcrypt --with-mhash --with-pcre-dir --with-pcre-regex=/usr/local --enable-shmop --enable-sockets --enable-sysvmsg --enable-sysvsem --enable-sysvshm --enable-wddx --with-xsl --enable-zip --with-geoip --enable-filter --enable-hash --enable-igbinary --with-mysqli --enable-tokenizer --enable-xmlreader --enable-xmlwriter --enable-posix --enable-gd-native-ttf --with-t1lib --with-jpeg-dir=/usr/local --with-png-dir=/usr/local --with-freetype-dir=/usr/local --with-vpx-dir=/usr/local --with-imagick=/usr/local --enable-redis --disable-redis-session --enable-redis-igbinary --enable-timezonedb --enable-fileinfo --enable-intl --with-kerberos --enable-raphf --enable-propro --with-http-libevent-dir=/usr/local --with-http --enable-opcache --with-tidy --with-librabbitmq-dir=/usr/local --with-amqp --with-libsodium --with-ssh2=shared
[...]
checking for curl/curl.h... found in /usr/local
checking for curl-config... found: /usr/local/bin/curl-config
checking for curl version >= 7.18.2... 7.58.0
checking for HTTP2 support in libcurl... yes
checking for SSL support in libcurl... yes
checking for OpenSSL support in libcurl... no
checking for GnuTLS support in libcurl... yes
checking gnutls.h usability... no
checking gnutls.h presence... no
checking for gnutls.h... no
checking for NSS support in libcurl... no
checking for SecureTransport support in libcurl... no
checking for GSKit support in libcurl... no
checking for ares support in libcurl... no
checking whether CURLOPT_TLSAUTH_TYPE expects CURL_TLSAUTH_SRP or literal "SRP"... "SRP"
checking for default SSL CA info/path... path:/etc/ssl/certs, info:/etc/ssl/certs/ca-certificates.crt


cd /usr/local/src/php-7.2.2
rm -R ext/amqp 2>/dev/null ; mkdir ext/amqp ; cp -R ../amqp-1.9.3/* ext/amqp/
rm -R ext/geoip 2>/dev/null ; mkdir ext/geoip ; cp -R ../geoip-1.1.1/* ext/geoip/
rm -R ext/igbinary 2>/dev/null ; mkdir ext/igbinary ; cp -R ../igbinary-2.0.5/* ext/igbinary/
rm -R ext/redis 2>/dev/null ; mkdir ext/redis ; cp -R ../redis-3.1.6/* ext/redis/
rm -R ext/imagick 2>/dev/null ; mkdir ext/imagick ; cp -R ../imagick-3.4.3/* ext/imagick/
rm -R ext/timezonedb 2>/dev/null ; mkdir ext/timezonedb ; cp -R ../timezonedb-2017.3/* ext/timezonedb/
rm -R ext/ssh2 2>/dev/null ; mkdir ext/ssh2 ; cp -R ../ssh2-1.1.1/* ext/ssh2/
rm -R ext/libsodium 2>/dev/null ; mkdir ext/libsodium ; cp -R ../libsodium-php-1.0.7/* ext/libsodium/
cd /usr/local/src/php-7.2.2
rm configure 2>/dev/null ; ./buildconf --force ; make clean
./configure --prefix=/usr/local/php72 --disable-all --with-iconv=/usr/local/lib --with-icu-dir=/usr/local --enable-libxml --with-libxml-dir=/usr/local --enable-xml --enable-dom --enable-ctype --with-curl=/usr/local --enable-json --enable-session --enable-simplexml --enable-pdo --with-pdo-mysql --with-zlib=/usr/local --with-openssl --with-openssl-dir=/usr/local/lib --enable-soap --enable-bcmath --with-bz2 --enable-calendar --enable-exif --enable-ftp --with-gd --with-gettext --enable-mbstring --with-mhash --with-pcre-dir --with-pcre-regex=/usr/local --enable-shmop --enable-sockets --enable-sysvmsg --enable-sysvsem --enable-sysvshm --enable-wddx --with-xsl --with-libzip=/usr/local --enable-zip --with-geoip --enable-filter --enable-hash --enable-igbinary --with-mysqli --enable-tokenizer --enable-xmlreader --enable-xmlwriter --enable-posix --with-jpeg-dir=/usr/local --with-png-dir=/usr/local --with-xpm-dir=/usr/local --with-freetype-dir=/usr/local --with-webp-dir=/usr/local --with-imagick=/usr/local --enable-redis --disable-redis-session --enable-redis-igbinary --enable-timezonedb --enable-fileinfo --enable-intl --with-kerberos --enable-opcache --with-tidy --with-librabbitmq-dir=/usr/local --with-amqp --with-sodium --with-ssh2=shared
[...]
checking for cURL support... yes
checking for libcurl.pc... using /usr/local/lib/pkgconfig/libcurl.pc
checking for cURL 7.10.5 or greater... 7.58.0
checking for SSL support in libcurl... yes
checking how to run the C preprocessor... cc -E
checking for openssl support in libcurl... yes
checking openssl/crypto.h usability... yes
checking openssl/crypto.h presence... yes
checking for openssl/crypto.h... yes
checking for gnutls support in libcurl... no
checking for curl_easy_perform in -lcurl... yes
checking for curl_easy_strerror in -lcurl... yes
checking for curl_multi_strerror in -lcurl... yes