In php 7 a few tests do fail after phpng merge 

InterBase: BLOB test [ext/interbase/tests/004.phpt]

InterBase: transactions [ext/interbase/tests/005.phpt]

InterBase: array handling [ext/interbase/tests/007.phpt]

ibase_trans(): Basic test [ext/interbase/tests/ibase_trans_001.phpt]

If anyone wants to help , we need some hands here 

https://wiki.php.net/phpng-upgrading

Some changes are already done (You can watch the git history) and there is still work to be done both in interbase and pdo_firebird extensions 

https://github.com/php/php-src/commits/master/ext/interbase

https://github.com/php/php-src/commits/master/ext/pdo_firebird

Another big change if you watch the git history is 64bit cleanup 

https://wiki.php.net/rfc/size_t_and_int64_next