Error when compiling php5.6: configure: error: Cannot find OpenSSL's

My system is dbeian8.

apt-get update
sudo apt-get install apache2 apache2-dev
apt-get install build-essential
sudo apt-get install libxml2-dev libcurl4-openssl-dev libjpeg-dev libpng-dev libxpm-dev libmysqlclient-dev libpq -dev libicu-dev libfreetype6-dev libldap2-dev libxslt-dev
apt-get install libssl-dev libsslcommon2-dev
Before compiling the above, each package has been installed.

find / -name 'openssl'
/usr/include/x86_64-linux-gnu/openssl
/usr/include/openssl
/usr/share/doc/openssl
/usr/bin/openssl
/usr/local/ src/php-5.6.0/ext/openssl

Download and prepare php5.6
wget http://cn2.php.net/distributi...
xz -d php-5.6.0.tar.xz
tar xf php-5.6.0.tar -C /usr/ local/src/
groupadd www
useradd -g www -s /sbin/nologin -M www
cd /usr/local/src/php-5.6.0/

Starting compilation
./configure
--prefix=/usr/local/php56
--with-config-file-path=/usr/local/php56/etc
--enable-inline-optimization
--disable -debug
--disable-rpath
--enable-shared
--enable-opcache
--enable-fpm
--with-fpm-user=www
--with-fpm-group=www
--with -mysql=mysqlnd
--with-mysqli=mysqlnd
--with-pdo-mysql=mysqlnd
--with-gettext
--enable-mbstring
--with-iconv
--with-mcrypt
--with -mhash
--with-openssl
--enable-bcmath
--enable-soap
--with-libxml-dir
--enable-pcntl
--enable-shmop
--enable-sysvmsg
--enable -sysvsem
--enable-sysvshm
--enable-sockets
--with-curl
--with-zlib
--enable-zip
--with-bz2
--with-readline

Error report
configure: error: Cannot find OpenSSL's

Excuse me, how to solve it?

Reply content:

My system is dbeian8.

apt-get update
sudo apt-get install apache2 apache2-dev
apt-get install build-essential
sudo apt-get install libxml2-dev libcurl4-openssl-dev libjpeg-dev libpng-dev libxpm-dev libmysqlclient-dev libpq -dev libicu-dev libfreetype6-dev libldap2-dev libxslt-dev
apt-get install libssl-dev libsslcommon2-dev
Before compiling the above, each package has been installed.

find / -name 'openssl'
/usr/include/x86_64-linux-gnu/openssl
/usr/include/openssl
/usr/share/doc/openssl
/usr/bin/openssl
/usr/local/ src/php-5.6.0/ext/openssl

Download and prepare php5.6
wget http://cn2.php.net/distributi...
xz -d php-5.6.0.tar.xz
tar xf php-5.6.0.tar -C /usr/ local/src/
groupadd www
useradd -g www -s /sbin/nologin -M www
cd /usr/local/src/php-5.6.0/

Starting compilation
./configure
--prefix=/usr/local/php56
--with-config-file-path=/usr/local/php56/etc
--enable-inline-optimization
--disable -debug
--disable-rpath
--enable-shared
--enable-opcache
--enable-fpm
--with-fpm-user=www
--with-fpm-group=www
--with -mysql=mysqlnd
--with-mysqli=mysqlnd
--with-pdo-mysql=mysqlnd
--with-gettext
--enable-mbstring
--with-iconv
--with-mcrypt
--with -mhash
--with-openssl
--enable-bcmath
--enable-soap
--with-libxml-dir
--enable-pcntl
--enable-shmop
--enable-sysvmsg
--enable -sysvsem
--enable-sysvshm
--enable-sockets
--with-curl
--with-zlib
--enable-zip
--with-bz2
--with-readline

Error report
configure: error: Cannot find OpenSSL's

Excuse me, how to solve it?

openssl-dev is missing