ExistentialType check on UnsafeRawPointer

*** RESOLVED **
Hi,

Assertion failure when isExistentialType() is invoked on a function argument that is of UnsafeRawPointer type. Should I be filtering them before invoking isExistentialType() or is this a bug?

Type of Argument:$UnsafeRawPointer
Type of Swift Argument:UnsafeRawPointer
Assertion failed: (Index < Length && "Invalid index!"), function operator[], file $HOME/swift/llvm/include/llvm/ADT/ArrayRef.h, line 241.

--R