Re: program that compiles in C but not in C++?

From: Arthur J. O'Dwyer (ajo_at_nospam.andrew.cmu.edu)
Date: 01/10/04 

Date: Sat, 10 Jan 2004 12:35:30 -0500 (EST)

On Sat, 10 Jan 2004, [iso-8859-1] Nils O. Selåsdal wrote:
>
> In article <btn8v2$olk$1@daisy.noc.ucla.edu>, Digital Puer wrote:
> > I came across a question that asked for me to write a
> > small program that will compile in C but not in C++.
> > Any ideas?
> >
> > The only one I can think of is one that tries to
> > downcast a void * to a more specific pointer without
> > a cast:

> void foo(){
> unsigned char c = 0xfa;
> char *d = &c;
> }

  This certainly *looks* like it would require a diagnostic in C,
as well as in C++. gcc and g++ agree with me; 'unsigned char *'
and 'char *' are not assignment-compatible.

> void foo(){
> char or[] = "or";
> }

  This requires no diagnostic in either language. Maybe you're
thinking of

        char *or = "or";

which is fine in C, but I'm not sure whether C++ still allows this
or not. (I'm guessing it does, for backwards compatibility, but I
could easily be wrong.)

-Arthur

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