Joachim Breitner authored Mar 12, 2012 and Simon Marlow committed Mar 14, 2012

Real primops can take boxed arguments, and the Cmm code will receive the
pointer to the object on the Haskell heap, e.g. for unpackClosure#. To
be able to implement such a function in a "foreign prim" call, this
needs to be allowed as well. By only allowing Any here (instead of
arbitrary types), it is clearer that the function will not receive the
value in any marshalled form, but just the raw pointer. Haskell code
using such functions are likely to use unsafeCoerce# to turn a haskell
value into a value of type Any.