🚀 go-pugleaf

In <43n718$ns@Radon.Stanford.EDU> becker@Xenon.Stanford.EDU (Denizen of the Deep) writes:


>My reading of the standard is that there's no way to convert between
>a pointer to a function and a pointer to an object or incomplete
>type; i.e. doing so results in undefined behavior.
>
>My question is this: suppose I am on a machine which has the
>same representation for all pointer types and I want to write
>code only for this machine (I don't care about portability).
>
>What is the status of my program if it attempts such a conversion,
>given that I know exactly how the compiler is generating code and I know
>it does exactly what I want?  Is it legal but just not portable, or is
>it not even technically a legal C program (since the behavior is
>undefined rather than implementation-defined)?

If the conversion is performed via an assignment, a constraint is violated
and a diagnostic is required.  If it is done with a cast, it's only a
matter of undefined behaviour.

In both cases, I'd say the code is not technically a legal C program.

Dan
--
Dan Pop
CERN, CN Division
Email: Dan.Pop@mail.cern.ch 
Mail:  CERN - PPE, Bat. 31 R-004, CH-1211 Geneve 23, Switzerland