Leaks when calling 'newArgumentEncoderWithBufferIndex:reflection:' function on iOS Metal

I'm having trouble with memory leaks.

I want to get shader's reflection data from MTLFunction which is generated from precompiled shader files. These files are compiled with Metal Developer Tools for Windows 2.3 and I use the following command options.

-x metal hoge.metal -std=ios-metal2.0 -o hoges.msl

To get these reflection data, I use the function newArgumentEncoderWithBufferIndex:reflection:. I can get the reflection data, but some memory leaks occur for each call this function, and I don't know how to release the memory of the reflection data.

This is a example code.

void Func(id<MTLFunction> _pShaderFunc)
{
    MTLAutoreleasedArgument reflection = nil;
    id<MTLArgumentEncoder> argEnc = [_pShaderFunc newArgumentEncoderWithBufferIndex:0 
                       reflection:&reflection];

    // some process...

    // [reflection release]; // run-time error.
    [argEnc release];
}

I tested this on iPhone 11 Pro Max with iOS 13.3.1, Xcode 13.1, and Mac mini(2018) with macOS Monterey 12.4. I compiled source files specifying the option -fno-objc-arc. I used the instrument Leaks, and I confirmed when this function isn't called, there were no memory leaks.

Could you give me some advice on how to resolve those leaks?