Description: ------------ Currently it's not possible without resource to install the last compatible extension using pecl install as it always selects the last existing version. With PHP 7 more and more extensions are going to drop support for older PHP versions in new major releases which breaks nearly all pecl install commands on PHP < 7. Test script: --------------- <PHP 5.6> pecl install apcu Expected result: ---------------- Last stable version 4.0.8 should be installed Actual result: -------------- WARNING: channel "pecl.php.net" has updated its protocols, use "pecl channel-update pecl.php.net" to update pecl/apcu requires PHP (version >= 7.0.0-dev), installed version is 5.6.5 No valid packages found install failed

This is a known problem, and the source of the problem is that pecl.php.net does not support the latest REST xml files in version 1.3 which would tell the PEAR installer which PHP version requirements the package has.

Supposedly @tyrael is working on implementing it, but I don't know the state.