[Issue 16564] KRRegion.empty sometimes returns Ternary.no

[via Digitalmars-d-bugs]

https://issues.dlang.org/show_bug.cgi?id=16564

--- Comment #7 from Temtaime <temtaime at gmail.com> ---
Oh, sorry, my mistake

import
        std.stdio,
        std.range,
        std.random,
        std.typecons,
        std.algorithm,

        std.experimental.allocator.building_blocks,

        core.memory;


void main()
{
    ubyte[128 * 1024] b;
    auto alloc = KRRegion!()(b);

    //alloc.switchToFreeList;

    auto k = alloc.allocate(128);
    assert(alloc.deallocate(k));

    assert(alloc.empty == Ternary.yes);
}

I don't know why but this simplest example asserts.
More complex tests are passed. Also it passes if the switch in uncommented

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