SDT0607: Missing or Invalid StructLayout

Property	Value
Rule ID	SDT0607
Title	Missing or Invalid StructLayout
Category	Network
Severity	Error

Cause

A custom struct passed as an argument in an [RPC] method lacks a explicit [StructLayout] attribute, uses LayoutKind.Auto, or defines a total byte Size of 0.

Rule Description

For fast blitting and zero-allocation binary network transport, custom structs used in network payloads must have a fixed, deterministic memory layout (LayoutKind.Sequential or LayoutKind.Explicit) with an explicitly defined size.

How to Fix Violations

Decorate the target struct definition with a explicit [StructLayout] specifying a non-auto layout and an exact byte size.

Violation:

public struct NetworkVector
{
    public float X;
    public float Y;
}

Fix:

using System.Runtime.InteropServices;
// ...
[StructLayout(LayoutKind.Sequential, Size = 8)]
public struct NetworkVector
{
    public float X;
    public float Y;
}

When to Suppress Warnings