Optimizing of explicit temporary storage

[Robert Dewar]

Mark Mitchell wrote:

> In C, even given just:
> 
>  (void) malloc(16);
> 
> it would be surprising to most programmers to optimize away the call 
> because malloc *does* have side-effects on real systems.  For example, 
> on UNIX, it is likely to call sbrk, which result in observable changes 
> in the process state.

Yes, but the condition of not surprising programmers is different from
the condition of conforming to the standard. Strictly from a standards
conformance point of view, these kinds of optimization seem perfectly
valid, but of course the criterion of not surprising programmers is
indeed a reasonable one!