What to do with opaque GMP objects which allows instantiation

Hello internals,

While working on something, I was using GMP for a test case and creating it
by doing akin to
$o = new GMP(5);

However, this does not create a GMP object initialized to 5, rather it
creates and sets the value to 0. This is because it does not define a
constructor, and the proper way to create GMP objects is to use the
procedural gmp_init() API.

GMP was one of the first resource to object conversions which was performed
in PHP 5.6.
More recent resource to object conversions prevent the instantiation of the
opaque object via new by defining a constructor that throws an Error to
point to the procedural API.
(something which would have saved me at least 30 minutes of debug time)

Opened an issue [1] and a PR was made [2] which I requested to target 8.1
as I was considering this a bugfix, however it seems that some people to
initialize the object by just writing new GMP().

Thus, the question, what should we do?

• Merge as a bug fix for 8.1.
• Target master (or 8.2.1) and align the behaviour with other opaque
  objects.
• Add a proper constructor that does the same as gmp_init() in master/8.2.1
• Add a mock constructor that allows instantiating without arguments, but
  throws an error if trying to provide an argument.
• Do nothing

Best regards,

George P. Banyard

[1] https://github.com/php/php-src/issues/10155
[2] https://github.com/php/php-src/pull/10158