Here's the list of things that we know are broken, or
are admittedly hackish stopgap measures or need to be fixed.

GC issues (copying allocator)

- immobile strings/buffers get freed during GC

Memory Leaks

- PIO subsystem leaks file handles (ParrotIO structures)
- regexen leak bitmaps
- string_to_cstring returns a malloced string, which isn't freed everywhere

Regexes

- are non reentrant due to interpreter global intstack

JIT

- 64 bit integers on 32 bit machines don't work
- parrot register inspection is incomplete (P-regs)

Configuration

- missing tests for processor features
- duplication e.g. nvsize/numvalsize

Docs

- a lot of outdated stuff

Portability issues

- conversion ops for machines without 1/2/4 byte integer data types
- 32 bit pointer/64 bit integer and vv.
- dynamic library loading

Tests

- ~1/3 of opcodes are uncovered by tests
- src/tests are not supported on all platforms

Utilities

- lib/Parrot/PackFile.pm does it's own packing & unpacking, which is
  not capable of reading the dir_format=1 PBC format. Non native floats
  are also not implemented.

- the Parrot debugger pdb: "eval" is b0rken, this needs linking
  to libimcc (which we don't have yet ;-)

Classes

- To PerlClass or not to PerlClass, that is the question. The class
  hierarchy should be reworked (e.g. Boolean->PerlInt->Scalar).

Undecided stuff

- data type of hashs store
- string_set - string header reusing
- multi key opcodes

Unimplemented

- overflow detection/promotion to bigint/float types
s. TODO for more
