// (12,18): error CS8107: Feature 'default interface implementation' is not available in C# 7. Please use language version 8.0 or greater.
// (12,18): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (13,18): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (6,18): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (7,18): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (15,18): error CS8107: Feature 'default interface implementation' is not available in C# 7. Please use language version 8.0 or greater.
// (15,18): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (16,18): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (6,18): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (7,18): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (4,9): error CS8107: Feature 'default interface implementation' is not available in C# 7. Please use language version 8.0 or greater.
// (4,9): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (4,14): error CS8107: Feature 'default interface implementation' is not available in C# 7. Please use language version 8.0 or greater.
// (4,14): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (6,32): error CS8107: Feature 'default interface implementation' is not available in C# 7. Please use language version 8.0 or greater.
// (6,32): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (6,37): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (5,32): error CS8107: Feature 'default interface implementation' is not available in C# 7. Please use language version 8.0 or greater.
// (5,32): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (5,39): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (5,32): error CS8107: Feature 'default interface implementation' is not available in C# 7. Please use language version 8.0 or greater.
// (5,32): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
@@ -8885,18 +8896,18 @@ private enum E { zero, one }
var comp = CreateCompilation(text, parseOptions: TestOptions.Regular7);
comp.VerifyDiagnostics(
// (5,19): error CS8107: Feature 'default interface implementation' is not available in C# 7. Please use language version 8.0 or greater.
// (5,19): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (6,22): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (7,16): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (8,22): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (6,21): error CS8107: Feature 'default interface implementation' is not available in C# 7. Please use language version 8.0 or greater.
// (6,21): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (11,20): error CS8107: Feature 'default interface implementation' is not available in C# 7. Please use language version 8.0 or greater.
// (11,20): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.
// (12,23): error CS8652: The feature 'default interface implementation' is currently in Preview and *unsupported*. To use Preview features, use the 'preview' language version.