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Re: Function casting - UB?

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nroberts wrote:
> In C++ this would be totally undefined.  How about in C?  It works on
> my machine with my compiler...
>
> If it's UB, is it one of those rules that pretty much has to work
> anyway?  What I mean is things like the fact that it's UB to assign to
> one part of a union and read from another

I am not sure that that is undefined behavior. That's sort of what
unions are *for*.

> but it generally works and
> is a pretty important construct.  Is this like that?
>
> #include <stdio.h>
>
> typedef void (*fun)(int, int);
>
> void f(int i) {
> 	int q = 33;
> 	printf("%d %d\n", i, q);
> }
>
> int main(void) {
> 	fun funptr = (fun)f;
> 	funptr(3,2);
>
> 	return 0;
> }
>
> output => 3 33
>


--
Les Cargill

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Thread

Function casting - UB? nroberts <roberts.noah@gmail.com> - 2012-06-27 08:50 -0700
  Re: Function casting - UB? Eric Sosman <esosman@ieee-dot-org.invalid> - 2012-06-27 12:49 -0400
    Re: Function casting - UB? Heikki Kallasjoki <fis+usenet@zem.fi> - 2012-06-27 17:54 +0000
      Re: Function casting - UB? "io_x" <a@b.c.invalid> - 2012-06-28 18:58 +0200
  Re: Function casting - UB? Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-27 10:37 -0700
    Re: Function casting - UB? Johannes Bauer <dfnsonfsduifb@gmx.de> - 2012-06-28 09:23 +0200
      Re: Function casting - UB? Johannes Bauer <dfnsonfsduifb@gmx.de> - 2012-06-28 09:27 +0200
        Re: Function casting - UB? Jens Gustedt <jens.gustedt@loria.fr> - 2012-06-28 12:03 +0200
          Re: Function casting - UB? Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-29 11:10 -0700
      Re: Function casting - UB? Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-29 11:03 -0700
  Re: Function casting - UB? Les Cargill <lcargill99@comcast.com> - 2012-06-27 12:58 -0500
  Re: Function casting - UB? Les Cargill <lcargill99@comcast.com> - 2012-06-27 12:59 -0500
    Re: Function casting - UB? James Kuyper <jameskuyper@verizon.net> - 2012-06-27 14:45 -0400
      Re: Function casting - UB? "christian.bau" <christian.bau@cbau.wanadoo.co.uk> - 2012-06-27 14:55 -0700
        Re: Function casting - UB? Tim Rentsch <txr@alumni.caltech.edu> - 2012-06-27 17:44 -0700
          Re: Function casting - UB? Joshua Maurice <joshuamaurice@gmail.com> - 2012-07-07 16:46 -0700
            Re: Function casting - UB? Barry Schwarz <schwarzb@dqel.com> - 2012-07-08 09:19 -0700
              Re: Function casting - UB? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-08 11:13 -0700
                Re: Function casting - UB? Barry Schwarz <schwarzb@dqel.com> - 2012-07-08 15:24 -0700
                Re: Function casting - UB? Joshua Maurice <joshuamaurice@gmail.com> - 2012-07-08 18:12 -0700
                Re: Function casting - UB? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-10 10:40 -0700
            Re: Function casting - UB? Tim Rentsch <txr@alumni.caltech.edu> - 2012-07-08 11:06 -0700

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