nosilver4u on "[Plugin: EWWW Image Optimizer] EWWW Not Compatible with PHP 7?"

I try PHP 7 in new server for development before make a production site.
I active WP DEBUG and VIOLA, got awesome error.

Notice: Undefined variable: jpegtran_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 955
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 955
Notice: Undefined variable: jpegtran_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 957
Waing: Invalid argument supplied for foreach() in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 957
Notice: Undefined variable: jpegtran_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 955
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 955
Notice: Undefined variable: jpegtran_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 957
Waing: Invalid argument supplied for foreach() in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 957
Notice: Undefined variable: jpegtran_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 955
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 955
Notice: Undefined variable: jpegtran_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 957
Waing: Invalid argument supplied for foreach() in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 957
Notice: Undefined variable: jpegtran_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 955
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 955
Notice: Undefined variable: jpegtran_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 957
Waing: Invalid argument supplied for foreach() in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 957
Notice: Undefined variable: jpegtran_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 955
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 955
Notice: Undefined variable: jpegtran_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 957
Waing: Invalid argument supplied for foreach() in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 957
Notice: Undefined variable: jpegtran_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 955
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 955
Notice: Undefined variable: jpegtran_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 957
Waing: Invalid argument supplied for foreach() in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 957
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 967
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 967
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 967
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 967
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 967
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 967
Notice: Undefined variable: optipng_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 979
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 979
Notice: Undefined variable: optipng_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 979
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 979
Notice: Undefined variable: optipng_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 979
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 979
Notice: Undefined variable: optipng_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 979
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 979
Notice: Undefined variable: optipng_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 979
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 979
Notice: Undefined variable: optipng_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 979
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 979
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 989
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 989
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 989
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 989
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 989
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 989
Notice: Undefined variable: gifsicle_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1001
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1001
Notice: Undefined variable: gifsicle_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1001
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1001
Notice: Undefined variable: gifsicle_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1001
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1001
Notice: Undefined variable: gifsicle_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1001
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1001
Notice: Undefined variable: gifsicle_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1001
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1001
Notice: Undefined variable: gifsicle_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1001
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1001
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1011
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1011
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1011
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1011
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1011
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1011
Notice: Undefined variable: convert_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1067
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1067
Notice: Undefined variable: convert_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1067
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1067
Notice: Undefined variable: convert_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1067
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1067
Notice: Undefined variable: convert_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1067
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1067
Notice: Undefined variable: convert_version in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1067
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1067
Notice: Undefined variable: nice_output in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1086
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1086
Notice: Undefined variable: nice_output in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1086
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1086
Notice: Undefined variable: nice_output in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1086
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1086
Notice: Undefined variable: nice_output in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1086
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1086
Notice: Undefined variable: nice_output in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1086
Waing: exec() has been disabled for security reasons in /home/admin/domainname.com/wp-content/plugins/ewww-image-optimizer/ewww-image-optimizer.php on line 1086

I installing all libraries like jpegtran and others but EWWW can't read it in WordPress admin.

This is BUG or UNCOMPATIBLE with PHP 7?

Server Information:
- CENTOS 6.8
- Nginx-proxy with PHP-FPM
- PHP 7.0.6

https://wordpress.org/plugins/ewww-image-optimizer/

enable the exec() function, and it should work fine. Otherwise, EWWW works fine with PHP 7, tested myself on various occasions.