Merge pull request #9769 from practicalswift/swiftc-28752-hasinterfacetype-no-interface-type-was-set
diff --git a/validation-test/compiler_crashers/28752-hasinterfacetype-no-interface-type-was-set.swift b/validation-test/compiler_crashers/28752-hasinterfacetype-no-interface-type-was-set.swift
new file mode 100644
index 0000000..10271f6
--- /dev/null
+++ b/validation-test/compiler_crashers/28752-hasinterfacetype-no-interface-type-was-set.swift
@@ -0,0 +1,10 @@
+// This source file is part of the Swift.org open source project
+// Copyright (c) 2014 - 2017 Apple Inc. and the Swift project authors
+// Licensed under Apache License v2.0 with Runtime Library Exception
+//
+// See https://swift.org/LICENSE.txt for license information
+// See https://swift.org/CONTRIBUTORS.txt for the list of Swift project authors
+
+// REQUIRES: asserts
+// RUN: not --crash %target-swift-frontend %s -emit-ir
+@objc protocol P{typealias e:P{}var a}{}extension P{typealias e:P
