Hi, internals.
I had incorrect knowledge the `serialize_precision` until recently.
I knew that setting this to `-1` would use a `long double`, but I didn't know that the number of digits would not be `17`.
I've looked through RFC related to this.
https://wiki.php.net/rfc/precise_float_value
There doesn't seem to be a setting that allows you to use `long double` and `mode2` at the same time at the moment.
I think there are various methods, such as a simple method such as simply setting `serialize_precision = -2`, or a method of adding another new setting item.
When using long doubles, it is somewhat inconvenient not to be able to display all digits with `var_dump()` or `debug_zval_dump()` when debugging.
(I use the word "inconvenient" because there is probably an alternative method.)
What do you think?
Saki
