RE: Cygwin PHP (all available versions) has a hard 4MB memory limit

[km2z7kca0oge@opayq.com]

> You told us nothing about what versions of Windows, Cygwin, and PHP you are running, so WAG, either:
Wow Brian, what a rude response. I definitely followed the problem reporting guide, and didn't realise you'd need information overload that probably doesn't relate to the case at hand. When reporting bugs I always give as much info as I believe is needed in helping, there's no need to snap.

I gave lots of information, such as:
  - It applies to all bundled versions of PHP from the `setup-x86-64.exe`.
  - That I've reproduced it on multiple (two) machines, including one of those being a machine that has never had (and so a fresh install of) Cygwin with just PHP added.
  - Compiling PHP from source doesn't produce this issue so it's something to do with the bundled version only

For extra information, both machines tested are:
  - Windows 10 64-bit (10.0.18363)
  - One machine is 16GB, the other 8GB RAM.
  - All PHP versions from the `setup-x86-64.exe` (7.3.4-1 and 7.1.16-1)

> - you have defaulted to or specified a PHP configuration limit of 4MB memory for PHP tasks, or
Nope, as shown in the output of my example, the memory limit is set to 128MB:
> Output:
> $ php test.php
> 128M <--- This here shows the configured memory limit
> PHP Fatal error:  Out of memory (allocated 4194304) (tried to allocate 2097184 bytes) in /c/Users/JackBlower/tmp-safe/test.php on line 5

> including copying verbatim all error messages seen
Here, the message was included in my initial email: > PHP Fatal error:  Out of memory (allocated 4194304) (tried to allocate 2097184 bytes) in /c/Users/JackBlower/tmp-safe/test.php on line 5

> - if you're running 32 bit Cygwin, possibly under 32 bit Windows, you have probably run out of heap space from installing too many packages requiring too many DLLs.
Nope all 64-bit, I would've mentioned if not.

> and PHP build configurations and logs.
See the output below for some more info, either way this is a pre-packaged version of PHP with very little changed from default configuration.

------------------------------
> Greetings, km2z7kca0oge--- via Cygwin!
Hey Andrey,

I've tried your script and I hit the 128MB limit, as expected. So maybe it's to do with the `http` wrapper. Could you try my version of the script please and see how you get on?

I first bumped into this problem when I rolled back from composer 2.X to 1.X which uses more memory.

I generated an 800MB file using: ` fsutil file createnew 800mega 838860800` and then ran your script you provided substituting your backup for the 800 MB file I generated.

The output of the script is below:
```
$ ./test-mailing-list.php
#!/usr/bin/env php
<?= file_get_contents(__FILE__);
phpinfo(1);
echo ini_get('memory_limit'), "\n";
print number_format(strlen(file_get_contents('800mega')));
phpinfo();
phpinfo()
PHP Version => 7.3.7

System => CYGWIN_NT-10.0-18363 AML0147 3.1.6-340.x86_64 2020-07-09 08:20 UTC x86_64
Build Date => Jul 21 2019 16:57:32
Server API => Command Line Interface
Virtual Directory Support => disabled
Configuration File (php.ini) Path => /etc
Loaded Configuration File => /etc/php.ini
Scan this dir for additional .ini files => /etc/php.d
Additional .ini files parsed => /etc/php.d/bcmath.ini,
/etc/php.d/bz2.ini,
/etc/php.d/curl.ini,
/etc/php.d/fileinfo.ini,
/etc/php.d/gd.ini,
/etc/php.d/gmp.ini,
/etc/php.d/intl.ini,
/etc/php.d/json.ini,
/etc/php.d/ldap.ini,
/etc/php.d/mbstring.ini,
/etc/php.d/pdo_mysql.ini,
/etc/php.d/pdo_pgsql.ini,
/etc/php.d/pdo_sqlite.ini,
/etc/php.d/phar.ini,
/etc/php.d/posix.ini,
/etc/php.d/simplexml.ini,
/etc/php.d/sockets.ini,
/etc/php.d/sodium.ini,
/etc/php.d/sqlite3.ini,
/etc/php.d/tokenizer.ini,
/etc/php.d/vld.ini,
/etc/php.d/xmlwriter.ini,
/etc/php.d/zip.ini,
/etc/php.d/zlib.ini

PHP API => 20180731
PHP Extension => 20180731
Zend Extension => 320180731
Zend Extension Build => API320180731,NTS
PHP Extension Build => API20180731,NTS
Debug Build => no
Thread Safety => disabled
Zend Signal Handling => enabled
Zend Memory Manager => enabled
Zend Multibyte Support => provided by mbstring
IPv6 Support => enabled
DTrace Support => disabled

Registered PHP Streams => https, ftps, php, file, glob, data, http, ftp, compress.bzip2, compress.zlib, zip, phar
Registered Stream Socket Transports => tcp, udp, unix, udg, ssl, sslv3, tls, tlsv1.0, tlsv1.1, tlsv1.2
Registered Stream Filters => string.rot13, string.toupper, string.tolower, string.strip_tags, convert.*, consumed, dechunk, bzip2.*, zlib.*

This program makes use of the Zend Scripting Language Engine:
Zend Engine v3.3.7, Copyright (c) 1998-2018 Zend Technologies
128M
PHP Fatal error:  Allowed memory size of 134217728 bytes exhausted (tried to allocate 838869024 bytes) in /c/Users/JackBlower/tmp-safe/test-mailing-list.php on line 5
```

Notice how this time it's running out of memory at 128MB and has the "Allowed memory size" error instead of the "Out of memory" error from before.

Many Thanks,

Jack