Regression test for rdar://problem/113492450

Author: slavapestov

validation-test/compiler_crashers_2_fixed/rdar113492450.swift

@@ -0,0 +1,24 @@
+// RUN: %target-swift-frontend -emit-ir %s -disable-availability-checking
+
+public protocol SomeObject {}
+
+public struct VariadicObjectBox<each S: SomeObject> {
+    public let object: (repeat each S)
+}
+
+@resultBuilder
+public struct VariadicObjectBoxBuilder {
+    public static func buildBlock<each S: SomeObject>(_ object: (repeat each S)) -> VariadicObjectBox<repeat each S> {
+        VariadicObjectBox(object: (repeat each object))
+    }
+}
+
+public struct ObjectContainer {
+    public init<each S: SomeObject>(box: VariadicObjectBox<repeat each S>) {
+        // This init compiles
+    }
+    
+    public init<each S: SomeObject>(@VariadicObjectBoxBuilder _ builder: () -> VariadicObjectBox<repeat each S>) {
+        // This init crashes on compilation
+    }
+}