AssemblyBuilderImpl.DefinePersistedAssembly has trouble with ReadOnlySpan methods #96469
Description
Repro (add this somewhere in the System.Reflection.Emit tests):
[Fact]
public void Repro()
{
using (TempFile file = TempFile.Create())
{
AssemblyBuilder ab = AssemblySaveTools.PopulateAssemblyBuilderTypeBuilderAndSaveMethod(out TypeBuilder type, out MethodInfo saveMethod);
MethodBuilder method = type.DefineMethod("M1", MethodAttributes.Public, null, null);
ILGenerator ilGenerator = method.GetILGenerator();
LocalBuilder span = ilGenerator.DeclareLocal(typeof(ReadOnlySpan<char>));
LocalBuilder str = ilGenerator.DeclareLocal(typeof(string));
ilGenerator.Emit(OpCodes.Ldstr, "hello");
ilGenerator.Emit(OpCodes.Call, typeof(MemoryExtensions).GetMethod("AsSpan", [typeof(string)])!);
ilGenerator.Emit(OpCodes.Stloc, span);
ilGenerator.Emit(OpCodes.Ldloca_S, span);
ilGenerator.Emit(OpCodes.Ldc_I4_1);
ilGenerator.Emit(OpCodes.Call, typeof(ReadOnlySpan<char>).GetMethod("Slice", [typeof(int)])!);
ilGenerator.Emit(OpCodes.Stloc, span);
ilGenerator.Emit(OpCodes.Ldloca_S, span);
ilGenerator.Emit(OpCodes.Constrained, typeof(ReadOnlySpan<char>));
ilGenerator.Emit(OpCodes.Callvirt, typeof(object).GetMethod("ToString"));
ilGenerator.Emit(OpCodes.Stloc, str);
ilGenerator.EmitWriteLine(str);
ilGenerator.Emit(OpCodes.Ret);
type.CreateType();
saveMethod.Invoke(ab, [file.Path]);
Type typeFromDisk = Assembly.LoadFile(file.Path).GetType("MyType");
typeFromDisk.GetMethod("M1").Invoke(Activator.CreateInstance(typeFromDisk), null);
}
}That fails with:
Discovering: System.Reflection.Emit.Tests (method display = ClassAndMethod, method display options = None)
Discovered: System.Reflection.Emit.Tests (found 632 of 633 test cases)
Starting: System.Reflection.Emit.Tests (parallel test collections = on, max threads = 12)
System.Reflection.Emit.Tests.AssemblySaveMethodBuilderTests.Repro [FAIL]
System.MissingMethodException : Method not found: 'System.ReadOnlySpan`1<Char> System.ReadOnlySpan`1.Slice(Int32)'.
Stack Trace:
at MyType.M1()
at System.RuntimeMethodHandle.InvokeMethod(Object target, Void** arguments, Signature sig, Boolean isConstructor)
D:\repos\runtime\src\coreclr\System.Private.CoreLib\src\System\Reflection\MethodBaseInvoker.CoreCLR.cs(36,0): at System.Reflection.MethodBaseInvoker.InterpretedInvoke_Method(Object obj, IntPtr* args)
D:\repos\runtime\src\libraries\System.Private.CoreLib\src\System\Reflection\MethodBaseInvoker.cs(57,0): at System.Reflection.MethodBaseInvoker.InvokeWithNoArgs(Object obj, BindingFlags invokeAttr)
Finished: System.Reflection.Emit.Tests