Access violation in clrjit.dll on Unsafe.CopyBlockUnaligned with constant 0 copy length #12773
Description
On 3.0.0-preview5-27626-15 and 3.0.0-preview6-27728-04 (Windows 10 1809, x64), attempting to run this:
var destination = new byte[1];
var source = new byte[1];
Unsafe.CopyBlockUnaligned(ref destination[0], ref source[0], 0);
results in an access violation in clrjit.dll.
There is no issue if the parameter is not constant, like so:
[MethodImpl(MethodImplOptions.NoInlining)]
public static void Trub(uint copyCount)
{
var destination = new byte[1];
var source = new byte[1];
Unsafe.CopyBlockUnaligned(ref destination[0], ref source[0], copyCount);
}
public static void Test()
{
Trub(0);
}
Changing the above MethodImpl to AggressiveInlining reintroduces the access violation.
Disabling optimizations avoids the issue. Does not occur on 2.1.11 or 2.2.3.
