(PHP 7 >= 7.4.0)
FFI::cast — Performs a C type cast
   FFI::cast() creates a new FFI\CData
   object, that references the same C data structure, but is associated with a different type.
   The resulting object does not own the C data, and the source ptr
   must survive the result. The C type may be specified as a string with any
   valid C type declaration or as FFI\CType object, created before.
   If this method is called statically, it must only use predefined C type names (e.g.
   int, char, etc.); if the method is called as
   instance method, any type declared for the instance is allowed.
  
Returns the freshly created FFI\CData object.