ext/bcmath: null should not be supported for operator overloading + comparison issues

[Girgias]

@SakiTakamachi you have memory leaks with the handling of the comparison operators and some conversions to string which don't make much sense to me (namely array to string).

[SakiTakamachi]

@Girgias
Thanks for catching this!

[SakiTakamachi]

I forgot to do this on failure.

if (Z_TYPE_P(op1) != IS_OBJECT) {
	bc_free_num(&n1);
}

if (Z_TYPE_P(op2) != IS_OBJECT) {
	bc_free_num(&n2);
}

[nielsdos]

This is fine, I have one minor remark/nit

[nielsdos]

If you declare int ret = ZEND_UNCOMPARABLE; at the start of the function, then you can put the failure label at line 1276, which would reduce code duplication.

[Girgias]

Done, sorry for the delay

[SakiTakamachi]

LGTM, thanks!

edit:
Please correct only the points mentioned by Niels :)

[Girgias]

CI is failing because of cURL tests and a failure to set up MySQL