From da3155249b1c1c74ed6eb694fea4a4a02c5c6de0 Mon Sep 17 00:00:00 2001
From: Arnold Schwaighofer <aschwaighofer@apple.com>
Date: Mon, 18 Mar 2019 13:02:27 -0700
Subject: [PATCH] Sema: Don't add dynamic to defer bodies

---
 lib/Sema/TypeCheckAttr.cpp                | 6 ++++++
 test/SILGen/dynamically_replaceable.swift | 6 ++++++
 2 files changed, 12 insertions(+)

diff --git a/lib/Sema/TypeCheckAttr.cpp b/lib/Sema/TypeCheckAttr.cpp
index 6c6fa7edad101..532a1631601f6 100644
--- a/lib/Sema/TypeCheckAttr.cpp
+++ b/lib/Sema/TypeCheckAttr.cpp
@@ -2566,6 +2566,12 @@ void TypeChecker::addImplicitDynamicAttribute(Decl *D) {
       D->getAttrs().hasAttribute<InlinableAttr>())
     return;
 
+  if (auto *FD = dyn_cast<FuncDecl>(D)) {
+    // Don't add dynamic to defer bodies.
+    if (FD->isDeferBody())
+      return;
+  }
+
   if (auto *VD = dyn_cast<VarDecl>(D)) {
     // Don't turn stored into computed properties. This could conflict with
     // exclusivity checking.
diff --git a/test/SILGen/dynamically_replaceable.swift b/test/SILGen/dynamically_replaceable.swift
index 714375767ce66..1aa58dae1a93f 100644
--- a/test/SILGen/dynamically_replaceable.swift
+++ b/test/SILGen/dynamically_replaceable.swift
@@ -356,3 +356,9 @@ func getsetX(_ x: Int) -> Int {
 dynamic func funcWithDefaultArg(_ arg : String = String("hello")) {
   print("hello")
 }
+
+// IMPLICIT-LABEL: sil private [ossa] @$s23dynamically_replaceable6$deferL_yyF
+var x = 10
+defer {
+  let y = x
+}