All these functions use the coercion of zvals to string. We need to figure out where the deprecation is relevant (where it can occur) and where it is intended.
[ ] zval_get_string_func
[ ] php_implode
[ ] implode (implode(['foo', true, false]))
[ ] zend_get_callable_name_ex
[ ] zend_try_compile_cv ($foo->{true} = 'bar')
[x] zend_ini_add_string Only used in the INI file parser
For zend_get_callable_name_ex() I don't think it can ever be anything else other than string/array/object, probably would want to replace the default branch.
Spoiler I was wrong
All these functions use the coercion of zvals to string. We need to figure out where the deprecation is relevant (where it can occur) and where it is intended.
zend_ini_add_stringOnly used in the INI file parser