PHP 7.0 and MySQL start-up error “undefined symbol: mysqlnd_allocator in Unknown”

Question

Getting this warning on a custom-compiled version of PHP7, even when running php -v.

Tried all solutions posted. What could cause this?

Answer 1

I found that I had

extension=pdo_mysql

uncommented in my php.ini file and this was causing the problem. Libraries are loaded by the files in the /etc/php/7.4/cli/conf.d/ file on my system and don't need to be loaded by uncommenting lines in the php.ini file.