The "no gc" crowd

[Justin Whear]

On Wed, 09 Oct 2013 22:30:05 +0200, Adam D. Ruppe wrote:

> On Wednesday, 9 October 2013 at 20:10:40 UTC, Justin Whear wrote:
>> Related to the latter, it would be really nice to be able to prove that
>> a section of code makes no heap allocations/GC collections.
> 
> As a quick temporary thing, how about gc_throw_on_next(); ?
> 
> That'd just set a thread local flag that gc_malloc checks and if it is
> set, immediately resets it and throws an AllocAssertError. My thought is
> this could be quickly and easily implemented pending a better solution
> and in the mean time can be used in unit tests to help check this stuff.

So user-code would look like this?

    // Set up code, GC is fine here
    ...

    // Entering critical loop (which may run for months at a time)
    debug GC.throw_on_next(true);
    while (true)
    {
       ...
    }

    // Tear-down code, GC is fine here
    // (though unnecessary as the process is about to exit)
    debug GC.throw_on_next(false);
    ...

Something like this would make testing simpler and is probably much more 
feasible than deep static analysis.