'class' : the 'structlayout' attribute can only be applied to a managed-class or value-type
The layout attribute can only be used with managed classes or value types.
The following sample generates C3268:
#using <mscorlib.dll> [ structlayout(sequential) ] class A { // C3268 }; /* use the following class definition to resolve the error __gc class A { }; */ void main() { }