[mcs] Implements C# 7.2 readonly structs

10 files changed, 94 insertions, 1 deletions

diff --git a/mcs/errors/cs0106-11.cs b/mcs/errors/cs0106-11.cs
new file mode 100644
index 00000000000..9aa99e36bc6
--- /dev/null
+++ b/mcs/errors/cs0106-11.cs
@@ -0,0 +1,7 @@
+// CS0106: The modifier `readonly' is not valid for this item
+// Line: 6
+// Compiler option: -langversion:latest
+
+readonly interface I
+{
+}
diff --git a/mcs/errors/cs0459-5.cs b/mcs/errors/cs0459-5.cs
new file mode 100644
index 00000000000..fa2cfd27dae
--- /dev/null
+++ b/mcs/errors/cs0459-5.cs
@@ -0,0 +1,13 @@
+// CS0459: Cannot take the address of `this' because it is read-only
+// Line: 11
+// Compiler options: -unsafe -langversion:latest
+
+readonly struct X
+{
+	unsafe void Test ()
+	{
+		fixed (X* x = &this) {
+
+		}
+	}
+}
diff --git a/mcs/errors/cs1604-2.cs b/mcs/errors/cs1604-2.cs
new file mode 100644
index 00000000000..7116ba3dafa
--- /dev/null
+++ b/mcs/errors/cs1604-2.cs
@@ -0,0 +1,11 @@
+// CS1604: Cannot assign to `this' because it is read-only
+// Line: 8
+// Compiler options: -langversion:latest
+
+readonly struct S
+{
+	void Foo ()
+	{
+		this = new S ();
+	}
+}
\ No newline at end of file
diff --git a/mcs/errors/cs1605-2.cs b/mcs/errors/cs1605-2.cs
new file mode 100644
index 00000000000..738899bfe4f
--- /dev/null
+++ b/mcs/errors/cs1605-2.cs
@@ -0,0 +1,16 @@
+// CS1605: Cannot pass `this' as a ref or out argument because it is read-only
+// Line: 14
+// Compiler options: -langversion:latest
+
+readonly struct X
+{
+	void Test (out X x)
+	{
+		x = new X ();
+	}
+	
+	void Run ()
+	{
+		Test (out this);
+	}
+}
diff --git a/mcs/errors/cs1644-56.cs b/mcs/errors/cs1644-56.cs
new file mode 100644
index 00000000000..de713efba4d
--- /dev/null
+++ b/mcs/errors/cs1644-56.cs
@@ -0,0 +1,7 @@
+// CS1644: Feature `readonly structs' cannot be used because it is not part of the C# 7.0 language specification
+// Line: 5
+// Compiler options: -langversion:7
+
+readonly struct S
+{
+}
\ No newline at end of file
diff --git a/mcs/errors/cs8145.cs b/mcs/errors/cs8145.cs
index cf3c5084722..ffbadfd67df 100644
--- a/mcs/errors/cs8145.cs
+++ b/mcs/errors/cs8145.cs
@@ -1,4 +1,4 @@
-// CS8145: Auto-implemented properties cannot return by reference
+// CS8145: Auto-implemented property `X.TestProp' cannot return by reference
 // Line: 6
 
 public class X
diff --git a/mcs/errors/cs8340-2.cs b/mcs/errors/cs8340-2.cs
new file mode 100644
index 00000000000..9236e9468b8
--- /dev/null
+++ b/mcs/errors/cs8340-2.cs
@@ -0,0 +1,13 @@
+// CS8340: `S.field': Instance fields in readonly structs must be readonly
+// Line: 6
+// Compiler options: -langversion:latest
+
+readonly partial struct S
+{
+
+}
+
+partial struct S
+{
+	int field;
+}
\ No newline at end of file
diff --git a/mcs/errors/cs8340.cs b/mcs/errors/cs8340.cs
new file mode 100644
index 00000000000..fb3376708b2
--- /dev/null
+++ b/mcs/errors/cs8340.cs
@@ -0,0 +1,8 @@
+// CS8340: `S.field': Instance fields in readonly structs must be readonly
+// Line: 6
+// Compiler options: -langversion:latest
+
+readonly struct S
+{
+	int field;
+}
\ No newline at end of file
diff --git a/mcs/errors/cs8341.cs b/mcs/errors/cs8341.cs
new file mode 100644
index 00000000000..c78406345fe
--- /dev/null
+++ b/mcs/errors/cs8341.cs
@@ -0,0 +1,8 @@
+// CS8341: Auto-implemented instance property `S.field' in readonly structs must be readonly
+// Line: 6
+// Compiler options: -langversion:latest
+
+readonly struct S
+{
+	int field { get; set; }
+}
\ No newline at end of file
diff --git a/mcs/errors/cs8342.cs b/mcs/errors/cs8342.cs
new file mode 100644
index 00000000000..d6d7f43f0bf
--- /dev/null
+++ b/mcs/errors/cs8342.cs
@@ -0,0 +1,10 @@
+// CS8342: `S.e': Field-like instance events are not allowed in readonly structs
+// Line: 6
+// Compiler options: -langversion:latest
+
+using System;
+
+readonly struct S
+{
+	event Action e;
+}
\ No newline at end of file