On Sunday, 30 August 2015 at 20:44:17 UTC, ponce wrote:
In the case the destructor isn't called by the GC, the call must succeed. GC.malloc(1) fits the bill but it's a waste of time and memory indeed. GC.free(<invalid-adress>) would fail in both cases if I understand correctly.
As you can see from the output (http://dpaste.dzfl.pl/aa004554034a), when GC.free(cast(void*)1) is called in main() it doesn't throw. It only throws in the destructor of A, because a GC collection is taking place.
If you look at the implementation, it is more or less guaranteed that:
a) GC.free() during collection -> InvalidMemoryOperationError [1] b) GC.free() with invalid pointer -> no-op [2]
Perhaps as a getter like GC.isRunning()?
Yeah, that's what I had in mind. But maybe it also makes sense to provide a way to take the GC lock? Of course, such method should definitely be marked as @system.
[1]: https://github.com/D-Programming-Language/druntime/blob/master/src/gc/gc.d#L879 [2]: https://github.com/D-Programming-Language/druntime/blob/master/src/gc/gc.d#L888
