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It's no longer permitted to create a System.Type instance for an array of System.Void.
Previous behavior
Previously, typeof(void).MakeArrayType() returned a System.Type instance.
New behavior
Starting in .NET 9, typeof(void).MakeArrayType() throws an exception.
Version introduced
.NET 9 Preview 1
Type of breaking change
This change is a behavioral change.
Reason for change
Array of System.Void is an invalid type. This type is rejected in some cases (for example, void[] in C# does not compile) and it's not possible to create arrays of this type.
.NET runtimes allowed this invalid type to be created in some situations. However, attempts to use this invalid type in other .NET runtime APIs often lead to unexpected behaviors. To make the behavior robust and consistent, it's better to disallow creating these invalid array types in all situations.
Recommended action
Remove code that tries to create a type for an array of System.Void.
Affected APIs
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