Re: -funsafe-loop-optimizations

[Robert Dewar <dewar at adacore dot com>]

Kai Henningsen wrote:

> 1. Assert somehow which calculations are/aren't supposed to overflow/wrap  
> (where I care)
>
> 2. Option A, have the compiler insert checking code to make sure, at  
> runtime, that what I asserted actually holds
>
> 3. Option B, have the compiler rely on my assertions for optimal  
> optimization
>
> 4. While I don't see an obvious use, presumably someone will also want  
> option C, ignore my assertions.
>
> And yes, I know where to find Pascal ;-)

You will do even better with Ada, which has all the above capabilities
and more :-)

The trouble with trying to do this in C is that it is really a
substantial language capability that you are trying to bolt on, and
it is hard to do that cleanly if it is not in the original language
design.