Here’s a memo on how to check the options specified for ./configure in PHP.

[Method 1] Check config.nice

Navigate to the source file directory where you ran ./configure and check the contents of the config.nice file.

cat config.nice

[Method 2] Check php -i

The second method is to check phpinfo.

php -i | grep './configure'

[Reference]：PHPのコンパイルオプションの調査 - takami_hirokiの日記

That’s all from the Gemba.