The get_addr op no longer returns the address of objects that don't implement the get_pointer() vtable. A new op, get_id, has been implemented to handle nqp's use case.
Such instances of get_addr have been replaced by get_id.
An alternative to the provided patch might be to use Hashes with the key type 'Hash_key_type_PMC_ptr', which would avoid the need to mangle keys manually.
use new get_id pirop to generate unique IDs for PMCs
Merge branch 'master' of git://github.com/perl6/nqp
Thanks for your patches, I've applied them to the new 'kill-useless-defaults' nqp branch, and bumped PARROT_REVISION in that branch.
I don't want to merge this into nqp/master until after the Rakudo release this month.
Contrary to what I wrote in the beginning (where I accidentally used an older copy of rakudo), rakudo builds fine on this branch, and passes all spectests.