On Wednesday 29 October 2008 00:55:42 Jorge Peixoto de Morais Neto wrote: > >> I mean to really know C, > >> that is, read a rigorous book such as "C: A Reference Manual" and be > >> able to write portable programs with well-defined behavior. Speaking > >> of well-defined behavior, do you know what happens when you cast a > >> float to an int, and the float is too big to fit into the int? > > > > Did oyu try it yourself and see? > > The point is that the behavior in this situation is "undefined". It > might do anything. Programming in C is different than programming in > Python.
Most likely the compiler will try to treat the float as an int and use the first 4 bytes of the float, ignoring the rest. This is insane though. I cannot think of any reason why one would ever want to treat the first 32 bits of a float as an int. It's not like you are casting a long to an int which can make sense - just discard the high bits. I reckon the standard would say this is undefined. Most compiler would bomb out with a compile error but give you an obscure flag to proceed anyway. If you want to commit suicide, C is quite happy to pass you the pills as long s you ask nicely -- alan dot mckinnon at gmail dot com
