php81 Unable to start pcre module

[ShadSterling (Shad Sterling)]

After upgrading to Monterey and following the usual macports update procedure, I installed the php81 port to replace the php that was included in earlier versions of macOS. Unfortunately, every invocation fails with the same error. For example, running/opt/local/bin/php81 --version outputs

Fatal error: Unable to start pcre module in Unknown on line 0

The pcre port is installed. Ports php80, php74 are also affected.

How can I collect whatever information is needed to diagnose this problem?

[ShadSterling (Shad Sterling)]

Looks like installing pcre2 fixed it. But pcre2 is listed as a library dependency of php81, so how did php81 get installed without one of its dependencies?

[ShadSterling (Shad Sterling)]

After running my routine update cycle for the first time after upgrading to Monterey, the error returned, and this time reinstalling pcre2 didn't fix it.

Turns out php73 is not affected, so until newer versions are usable I'll be using php73

[ryandesign (Ryan Carsten Schmidt)]

Replying to ShadSterling:

Fatal error: Unable to start pcre module in Unknown on line 0

Hmm, I haven't encountered this before. Googling this error, I found ​a page suggesting it could be caused by copies of libpcre in /usr/local/lib. Do you have anything in /usr/local/lib? If so, I recommend removing what you have in /usr/local; see wiki:FAQ#usrlocal.

Replying to ShadSterling:

Looks like installing pcre2 fixed it. But pcre2 is listed as a library dependency of php81, so how did php81 get installed without one of its dependencies?

I cannot imagine any way that that could have happened.

Replying to ShadSterling:

After running my routine update cycle for the first time after upgrading to Monterey, the error returned, and this time reinstalling pcre2 didn't fix it.

That's curious.

Turns out php73 is not affected, so until newer versions are usable I'll be using php73

That's curious too. If anything I would have expected you to say that php72 and earlier are not affected but php73 and later are. php72 and earlier use pcre while php73 and later use pcre2.

[ShadSterling (Shad Sterling)]

I have GPGMail and a few other things that install to /usr/local, so I'm not going to just remove it all, but there's nothing that looks like pcre in /usr/local/lib

This time I tried installing php81 -libedit and php81 -libedit+readline, both of which are also unaffected, so maybe the problem has something to do with libedit

What other information can I collect to diagnose this problem?