For large floats/integers, APFloat/APInt will allocate memory from the heap to represent these numbers.
Unfortunately, when we use a BumpPtrAllocator to allocate IntegerLiteral/FloatingLiteral nodes the memory associated with
the APFloat/APInt values will never get freed.
I introduce the class 'APNumericStorage' which uses ASTContext's allocator for memory allocation and is used internally by FloatingLiteral/IntegerLiteral.
Fixes rdar://7637185
llvm-svn: 112361
Douglas Gregor