Implicitly truncating stloc after dup seems to be miscompiled in RyuJIT

dup-stloc-jit-bug.il

.assembly extern mscorlib
{
  .publickeytoken = ( b7 7a 5c 56 19 34 e0 89 )
  .ver 4:0:0:0
}

.assembly 'StackTypes'
{
  .ver 0:0:0:0
}

.module StackTypes.exe
.corflags 0x00000001 // ILOnly

.class private auto ansi abstract sealed beforefieldinit Program
extends [mscorlib]System.Object
{
  .method public hidebysig static void Main (string[] args) cil managed 
  {
    .maxstack 8
    .entrypoint

    call void Program::InlineAssignByte()
    //call void Program::Int32OrNativeTests()

    ret
  } // end of method Main

  .method public static void InlineAssignByte()
  {
    .locals init (
      int8 local
    )
    ldstr "InlineAssignByte: WriteLine(local = {0})"
    ldc.i4 300
    dup
    stloc.0
    box int32
    call void [mscorlib]System.Console::WriteLine(string, object)
    ldstr "InlineAssignByte: local is {0}"
    ldloc.0
    box int32
    call void [mscorlib]System.Console::WriteLine(string, object)
    ret
  }
}