Value type fields should be portable

Cause

This rule checks that structures declared with explicit layout will align correctly when marshaled to unmanaged code on 64-bit platforms. IA-64 does not allow unaligned memory accesses and the process will crash if this violation is not fixed.

Rule Description

Structures with explicit layout containing misaligned fields cause crashes on 64-bit platforms.

How to Fix Violations

All fields that are smaller than 8 bytes must have offsets that are multiple of their size, and fields that are 8 bytes or greater must have offsets that are a multiple of 8. Another solution is to use LayoutKind.Sequential instead of LayoutKind.Explicit if reasonable.

When to Exclude Warnings

This warning should be excluded only if it occurs in error.