[Issue 23318] GCAllocator should not implement deallocate

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=23318

Dlang Bot <dlang-bot at dlang.rocks> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           Keywords|                            |pull

--- Comment #4 from Dlang Bot <dlang-bot at dlang.rocks> ---
@pbackus updated dlang/phobos pull request #8554 "Remove deallocate and
reallocate from GCAllocator" fixing this issue:

- Remove GCAllocator.deallocate

  This is necessary to make clients of GCAllocator (e.g., generic
  containers) usable in @safe code.

  Memory allocated by GC allocator will still be freed by the GC when it
  is no longer reachable.

  Rejected alternatives:

  - Making GCAllocator.deallocate a no-op method that always returns
    false. The documentation in std.experimental.allocator.building_blocks
    specifically says not to do that.

  - Special-casing client code for GCAllocator to avoid calling its
    'deallocate' method, while still calling 'deallocate' for other
    allocators.

  'deallocate' has been documented as an optional method since
  std.experimental.allocator was introduced in 2015 (commit 8b249a6240),
  so this change will not break code that correctly adheres to the
  documented allocator interface (i.e., checks for the presence of
  'deallocate' before calling it).

  Fixes issue 23318.

https://github.com/dlang/phobos/pull/8554

--