Why many programmers don't like GC?

[Ola Fosheim Grøstad]

On Thursday, 14 January 2021 at 13:10:14 UTC, sighoya wrote:
> On Thursday, 14 January 2021 at 13:08:06 UTC, Ola Fosheim 
> Grøstad wrote:
>
>> Because Java has a well defined virtual machine with lots of 
>> restrictions.
>
> So you're insisting this isn't possible in D?

It isn't possible in a meaningful way.

In system level programming languages you have to manually uphold 
the invariants needed to not break the GC collection algorithm.

So if you change to a significantly different collection model, 
the needed invariants will change.

The possible alternatives are:

1. Use "shared" to prevent GC allocated memory from entering 
other threads and switch to thread local GC. Then use ARC for 
shared.

2. Redefine language semantics/type system for a different GC 
model. This will break existing code.