Test case

test/IRGen/prespecialized-metadata/nestedtype.swift

@@ -0,0 +1,39 @@
+// RUN: %swift -prespecialize-generic-metadata -target %module-target-future  -emit-ir %s | %FileCheck %s -DINT=i%target-ptrsize -DALIGNMENT=%target-alignment
+
+// REQUIRES: VENDOR=apple || OS=linux-gnu
+// UNSUPPORTED: CPU=i386 && OS=ios
+// UNSUPPORTED: CPU=armv7 && OS=ios
+// UNSUPPORTED: CPU=armv7s && OS=ios
+
+@inline(never)
+func consume<T>(_ t: T) {
+  withExtendedLifetime(t) { t in
+  }
+}
+
+struct Container<T> {
+  struct NonFixed {
+
+    init( _ t: T) {
+        w = t
+    }
+
+    var w: T? = nil
+    var x = 1
+    var y = 1
+    var z = 1
+  }
+}
+
+
+func doit2() {
+  consume(Container.NonFixed(5))
+}
+
+doit2()
+
+// Make sure we use the generic witness table functions rather than specialized
+// ones. We do this for code size.
+
+// CHECK: @"$s10nestedtype9ContainerV8NonFixedVySi_GWV" =
+// CHECK-SAME: s10nestedtype9ContainerV8NonFixedVwtk