Invalid IL produced for an unused struct load from a ref local

[SingleAccretion]

Version Used: the P5 preview SDK, csc.dll had a product version of 4.2.0-4.22212.4+f2d278f9a5131b7944d6ac5fecf2ce5b0a98195f.

Steps to Reproduce:

Compile and run:

using System.Runtime.CompilerServices;

Problem(new Struct[1]);

[MethodImpl(MethodImplOptions.NoInlining)]
static void Problem(Struct[] a)
{
    ref var b = ref a[0];
    _ = b;
}

struct Struct { }

Expected Behavior: program exits successfully.

Actual Behavior: InvalidProgramException is thrown because the IL produced for Problem is not valid:

IL to import:
IL_0000  02                ldarg.0
IL_0001  16                ldc.i4.0
IL_0002  8f 24 00 00 02    ldelema      0x2000024
IL_0007  26                pop
IL_0008  25                dup          // The stack is empty at this point, there is nothing to "dup"
IL_0009  71 24 00 00 02    ldobj        0x2000024
IL_000e  26                pop
IL_000f  2a                ret