🚀 go-pugleaf

In article <1992Nov16.200843.5565@Princeton.EDU>, rhl@grendel.Princeton.EDU (Robert Lupton the Good) writes:
>    const int i = 0;
>    
>    (int)i = 1;				/* Fails */

The result of a cast is not an l-value and thus cannot be assigned to.

>    *(int *)&i = 1;			/* OK */

This is acceptable syntax, but results in undefined behavior since i is
defined as a const variable.  The compiler is allowed to place it in
read-only memory, which would cause the assignment to fail.

> I want to set
> the variable once in a private place just after mallocing it, in case
> you wonder why I am trying to get around a const restriction, and
> don't see why I can't just initialise it

That's a different case than your example: the memory that malloc()
returns is *not* defined with the const qualifier, just the pointer that
you are using to access it.  In that case the second method is well
defined and portable.
----
Larry Jones, SDRC, 2000 Eastman Dr., Milford, OH  45150-2789  513-576-2070
larry.jones@sdrc.com  or  ...uunet!sdrc!larry.jones
OK, what's the NEXT amendment say?  I know it's in here someplace. -- Calvin