dyld: Library not loaded: /usr/local/lib/libpng16.16.dylib with anything php related

Question 1

I suggest you run:

$ brew update && brew upgrade

Until couple of minutes ago I had this problem, too. Because I have an up to date PHP version, I solved it with:

$ brew reinstall php55

Question 2

I followed the above (never a bad idea to keep up to date with brew anyhow) and still had the same exact issue:

LAPTOP:folder Username$ php -v
dyld: Library not loaded: /usr/local/lib/libpng15.15.dylib
  Referenced from: /usr/local/bin/php
  Reason: image not found
Trace/BPT trap: 5

Then figured out a simpler way:

Search for your libpng version(s) on your box:

# Requires locate & updatedb for mac os x
# See Link [1] 
LAPTOP:folder Username$ locate libpng15.15.dylib
/Applications/GIMP.app/Contents/Resources/lib/libpng15.15.dylib
/usr/X11/lib/libpng15.15.dylib
/usr/local/Cellar/libpng/1.5.14/lib/libpng15.15.dylib

Make a symlink:

LAPTOP:folder Username$ ln -s /usr/local/Cellar/libpng/1.5.14/lib/libpng15.15.dylib /usr/local/lib/libpng15.15.dylib

Try again:

LAPTOP:folder Username$ php -v
PHP 5.3.26 (cli) (built: Aug 25 2013 16:07:23) 
Copyright (c) 1997-2013 The PHP Group
Zend Engine v2.3.0, Copyright (c) 1998-2013 Zend Technologies
    with Xdebug v2.2.3, Copyright (c) 2002-2013, by Derick Rethans

1) Mac OS X equivalent of locate

Question 3

It's because there's no symlinks for libpng. You need to link libpng again.

brew unlink libpng && brew link libpng

And you may get some error. I fixed that error by correcting permission. Maybe it's because of uninstalled macports.

sudo chown -R yourid:staff /usr/local/share/man/

Create link again and it'll work.

Question 4

I solved this by copying it over to the missing directory:

cp /opt/X11/lib/libpng15.15.dylib /usr/local/lib/libpng15.15.dylib

brew reinstall libpng kept installing libpng16, not libpng15 so I was forced to do the above.

Question 5

In my case it was libjpeg. All I had to do was run brew reinstall libjpeg and everything just worked!

Question 6

Just in case someone else runs into this problem I solved it by the following

brew update && brew upgrade # installs libpng 1.6

This caused an error with other packages requiring 1.5 which they were built with, so I linked it:

cd /usr/local/lib/
ln -s ../Cellar/libpng/1.5.18/lib/libpng15.15.dylib

Now they are both living in harmony and side by side for the different packages. It would be better to rebuild the packages that depend on 1.5, but this works as a quick bandage fix.

Question 7

I know this question has already an answer that gives a solution. But I want to give you my two cents to help people to understand the problem. Getting same issue I've created a specific question. I got same problem, but only with PHPStorm. And exactly when I try to run test from the editor.

dyld is the dynamic linker

I sow that dyld was looking for /usr/local/lib/libpng15.15.dylib but inside my /usr/local/lib/ there was not. In that folder, I got libpng16.16.dylib.

Thanks to a comment, I undestand that my /usr/bin/php was a pointer to php 5.5.8. Instead, ... /usr/local/bin/php was 5.5.14. PHPStorm worked with /usr/bin/php that is default configuration. When I run php via console, I run /urs/local/bin/php.

So, ... If you get some dyld error, maybe you have some wrong php configuration. That's the reason because

$ brew update && brew upgrade
$ brew reinstall php55

But I dont know why this do not solve the problem to me. Maybe because I have

Question 8

I also had this problem, and none of the solutions in this thread worked for me. As it turns out, the problem was that I had this line in ~/.bash_profile:

alias php="/usr/local/php/bin/php"

And, as it turns out, /usr/local/php was just a symlink to /usr/local/Cellar/php54/5.4.24/. So when I invoked php -i I was still invoking php54. I just deleted this line from my bash profile, and then php worked.

For some reason, even though php55 was now running, the php.ini file from php54 was still loaded, and I received this warning every time I invoked php:

PHP Warning:  PHP Startup: Unable to load dynamic library '/usr/local/Cellar/php54/5.4.38/lib/php/extensions/no-debug-non-zts-20100525/memcached.so' - dlopen(/usr/local/Cellar/php54/5.4.38/lib/php/extensions/no-debug-non-zts-20100525/memcached.so, 9): image not found in Unknown on line 0

To fix this, I just added the following line to my bash profile:

export PHPRC=/usr/local/etc/php/5.5/php.ini

And then everything worked as normal!

Question 9

I had this error that wasn't solved by brew update && brew upgrade. For some reason I needed to install it from scratch:

$ brew install libpng

Question 10

I had very hard time with this error :

Reason: Incompatible library version: php requires version 44.0.0 or later, but libpng16.16.dylib provides version 42.0.0 Trace/BPT trap: 6

I did all the above things with brew and much more ... but it wasn't this !

Check where your library is :

sudo find / -name libpng16.16.dylib

In my case here was the relevant result :

/usr/local/lib/libpng16.16.dylib
/usr/local/Cellar/libpng/1.6.34/lib/libpng16.16.dylib
/Applications/MAMP/Library/lib/libpng16.16.dylib
/opt/X11/lib/libpng16.16.dylib

So as I'm a MAMP user it turn out that the error appeared while I was trying to update from PHP 7.1.0 to 7.1.8 (last MAMP php available) as Symfony4 require at least 7.1.3

At the end I instaled the new version of MAMP and it worked (4.1 to 4.2). However be carreful when you're doing this, you need to backup first everything in your MAMP/htdoc folder. Also keep a backup of your custom compiled php version than can live in MAMP/bin/php. (In my case I had a special PHP version with Oracle drivers).

Also if you configured the MAMP php version to be your CLI php interpreter, you'll need to update the PATH in your .bash_profile

It should look something like this :

export PATH=/Applications/MAMP/bin/php/php7.1.8/bin:$PATH

I hope this can help.

Question 11

I got this problem after updating MAMP, and the custom $PATH I had set was wrong because of the new php version, so the wrong version of php was loaded first, and it was that version of php that triggered the error.

Updating the path in my .bash_profile fixed my issue.