Benchmark.cs

[MemoryDiagnoser]
public class BenchmarkMethodDelegateAllocations
{
    private readonly List<int> list = new List<int> { 1, 2, 3 };
    private int field = 2;

    [Benchmark(Baseline = true)]
    public int SafeMethod()
    {
        int res = 0;

        for (int i = 0; i < 1000; i++)
            res += safeMethod();

        return res;
    }

    [Benchmark]
    public int AllocatingMethod()
    {
        int res = 0;

        for (int i = 0; i < 1000; i++)
            res += allocatingMethod();

        return res;
    }

    private int safeMethod()
    {
        return 0;

        int local = 2;
        return list.Count(_ => 0 > local);
    }

    private int allocatingMethod()
    {
        return 0;

        int local = 2;
        return list.Count(_ => field > local);
    }
}

Method	Mean	Error	StdDev	Ratio	RatioSD	Gen 0	Gen 1	Gen 2	Allocated
SafeMethod	547.6 ns	1.08 ns	1.01 ns	1.00	0.00	-	-	-	-
AllocatingMethod	8,790.7 ns	209.87 ns	618.80 ns	16.92	0.67	0.9460	-	-	32000 B

dotnet/runtime issue