Cannot install mcrypt with homebrew and php7.4

Question

OS: macOS 11 (big sur)

Homebrew: 2.5.12

PEAR Version: 1.10.12

I just upgraded the php on my mac from php7.1 to php7.4 with homebrew (brew install [email protected]).

Then, when I try to install mcrypt extension, I got the error:

configure: error: mcrypt.h not found. Please reinstall libmcrypt.
ERROR: `/private/tmp/pear/install/mcrypt/configure --with-php-config=/usr/local/homebrew/opt/[email protected]/bin/php-config --with-mcrypt' failed

Here is what I did:

1. brew isntall mcrypt
2. install the pecl
3. sudo pecl install mcrypt -- The error goes here.

What I tried:

1. Located the mcrypt.h and put manually the file to the several locations (based on the php-config), not work.

2. Cleaned the brew and reinstall/relink the mcrypt(libmcrypt), not work.

3. Removed the legacy mcrypt files of the old brew version.

Answer 1

I ran into the same problem. So after installing libmcrypt with brew install mcrypt it seems like configure is not able to resolve the path to mcrypt.h automatically. It also does not work to specify the CPPFLAGS or giving the homebrew include path.

But I found a solution that works for me by giving pecl the install location of mcrypt in the Homebrew Cellar. This is what the following code does automatically:

pecl install mcrypt <<<"$(ls -d $(brew --prefix)/Cellar/mcrypt/* | tail -1)"