NativeAOT Reflection-free mode: enum.IsDefined() shows different output

[smhmhmd]

Description

The same code shows different output is different when executed using dotnet runtime or run as a NativeAOT (compiled in reflection-free mode). This difference shows only in Reflection-free mode (IlcDisableReflection is set to true in csproj)

The sample code is from here

Reproduction Steps

Compile code from here
For NativeAOT add these to the csproj file

 <ItemGroup>
     <PackageReference Include="Microsoft.DotNet.ILCompiler" Version="7.0.0-*" />
  </ItemGroup>

<PropertyGroup>
    <InvariantGlobalization>true</InvariantGlobalization>
    <!-- Note: Program fails only when reflection is completely disabled as below -->
    <IlcDisableReflection>true</IlcDisableReflection>
 </PropertyGroup>

Expected behavior

    'dotnet run' shows expected output
        $ dotnet run
            1: True
            64: False
            Rodent: True
            Dog: True
            Dog, Cat: False
            None: True
            NONE: False
            9: False

Actual behavior

   NativeAOT shows:
        $ ./enum-isdefined
            1: False
            64: False
            Rodent: False
            1: False
            3: False
            None: False
            NONE: False
            9: False

Regression?

No response

Known Workarounds

No response

Configuration

No response

Other information

No response

[dotnet-issue-labeler]

I couldn't figure out the best area label to add to this issue. If you have write-permissions please help me learn by adding exactly one area label.

[jkotas]

More usable reflection-free is tracked by #67193 . Enums behavior is one of the know issues of the current very experimental reflection-free mode.

Resolving as duplicate.