Bug 18853 – std.allocator: AllocatorList fails to allocate after a deallocation

///////////////////////////// test.d //////////////////////////// import std.algorithm.comparison; import std.experimental.allocator; import std.experimental.allocator.building_blocks.allocator_list; import std.experimental.allocator.building_blocks.region; import std.experimental.allocator.gc_allocator; void main() { AllocatorList!((n) => Region!GCAllocator(max(n, 4096)), GCAllocator) allocator; auto buf = allocator.allocate(2048); allocator.deallocate(buf); buf = allocator.allocate(4097); assert(buf.length); } ///////////////////////////////////////////////////////////////// At a glance, looks like it's caused by the thrashing protection not taking deallocations into account.

This was fixed by https://github.com/dlang/phobos/pull/6462.