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The following source code
public class B
public class AClass
public static int Foo(System.Type t, bool b = false, int x = 0)
public static int Foo(System.Type t, params int x)
public static int Foo(System.Type t, params B x)
public static void Main()
B b = new B();
produces ambiguity errors with mcs:
foo.cs(26,5): error CS0121: The call is ambiguous between the following methods or properties: `AClass.Foo(System.Type, params int)' and `AClass.Foo(System.Type, params B)'
foo.cs(13,21): (Location of the symbol related to previous error)
foo.cs(17,21): (Location of the symbol related to previous error)
Compilation failed: 1 error(s), 0 warnings
However, mono version 3.8 (and csc) seems to work fine with the code.
According to 22.214.171.124 from the C# language spec (5.0), the first method should be chosen (I think),
because it can be applied in the call below in its normal form?
Fixed in master