Issue

In Linux and Mac Os, I compile the source code of PHP 7.4.9. Run the following commands.

$ ./configure --prefix=/opt/php-7.4.9 --enable-fpm --with-pdo-mysql --with-zip --with-curl --enable-mbstring

I get the error message saying:

configure: error: The pkg-config script could not be found or is too old.  Make sure it
is in your PATH or set the PKG_CONFIG environment variable to the full
path to pkg-config.

Alternatively, you may set the environment variables LIBXML_CFLAGS
and LIBXML_LIBS to avoid the need to call pkg-config.
See the pkg-config man page for more details.

To get pkg-config, see <http://pkg-config.freedesktop.org/>.
See `config.log' for more details

Solution

It needs pkg-config.

Ubuntu/Debian

apt install pkg-config

Redhat/Centos

yum install -y pkgconfig

Archlinux OS

pacman -S pkgconf

Mac OS

brew install pkg-config