JIT: (bug) constant-folds typeof(void).IsPrimitive to true

[EgorBo]

The importer folds Type.IsPrimitive for a known System.Void type handle to true, disagreeing with reflection, which reports false for typeof(void).IsPrimitive.

Minimal Repro

using System;
using System.Runtime.CompilerServices;

class Program
{
    [MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.AggressiveOptimization)]
    static bool Folded() => typeof(void).IsPrimitive;

    [MethodImpl(MethodImplOptions.NoInlining | MethodImplOptions.NoOptimization)]
    static bool Runtime(Type t) => t.IsPrimitive;

    static void Main()
    {
        Console.WriteLine("folded:  " + Folded());
        Console.WriteLine("runtime: " + Runtime(typeof(void)));
    }
}

Expected

folded:  False
runtime: False

Actual

folded:  True
runtime: False

Notes

Compiler::impIntrinsic handles NI_System_Type_get_IsPrimitive by checking getTypeForPrimitiveValueClass, which returns a primitive type value for System.Void.
The fold should explicitly reject CORINFO_TYPE_VOID so it matches System.Type.IsPrimitive.

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[EgorBo]

Affected SDK versions:

• 9.0.318
• 10.0.401
• 11.0.100-rc.2.26467.112