No subject

| Package requirements
|
| Every package should fulfil the following requirements. Any
| requirements that are not met must be clearly explained and justified
| in the proposal.
|
| [...]
|
| - Compile on all operating systems and compilers that the platform
|   targets. [rationale-8.4] 

But I couldn't find any explictly stated list which compilers beyond GHC
(and which version(s) of GHC?) the HP actually wants to target.

Cheers,
  hvr