From 1a31f8df274c88aa56989d2e28caa96d5a3afc99 Mon Sep 17 00:00:00 2001
From: Richard Smith <richard-llvm@metafoo.co.uk>
Date: Wed, 12 Jun 2019 18:32:22 +0000
Subject: [PATCH] PR42220: take into account the possibility of aggregates with
 base classes when checking an InitListExpr for lifetime extension.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@363188 91177308-0d34-0410-b5e6-96231b3b80d8
---
 lib/Sema/SemaInit.cpp           |  3 +++
 test/CodeGenCXX/temporaries.cpp | 18 ++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/lib/Sema/SemaInit.cpp b/lib/Sema/SemaInit.cpp
index 25aff40f26..1a1d934798 100644
--- a/lib/Sema/SemaInit.cpp
+++ b/lib/Sema/SemaInit.cpp
@@ -6860,6 +6860,9 @@ static void visitLocalsRetainedByInitializer(IndirectLocalPath &Path,
                                               RK_ReferenceBinding, Visit);
       else {
         unsigned Index = 0;
+        for (; Index < RD->getNumBases() && Index < ILE->getNumInits(); ++Index)
+          visitLocalsRetainedByInitializer(Path, ILE->getInit(Index), Visit,
+                                           RevisitSubinits);
         for (const auto *I : RD->fields()) {
           if (Index >= ILE->getNumInits())
             break;
diff --git a/test/CodeGenCXX/temporaries.cpp b/test/CodeGenCXX/temporaries.cpp
index 294ff29a8e..d15e0fa05b 100644
--- a/test/CodeGenCXX/temporaries.cpp
+++ b/test/CodeGenCXX/temporaries.cpp
@@ -896,3 +896,21 @@ namespace Conditional {
   // CHECK: br label
   A &&r = b ? static_cast<A&&>(B()) : static_cast<A&&>(C());
 }
+
+#if __cplusplus >= 201703L
+namespace PR42220 {
+  struct X { X(); ~X(); };
+  struct A { X &&x; };
+  struct B : A {};
+  void g() noexcept;
+  // CHECK-CXX17-LABEL: define{{.*}} @_ZN7PR422201fEv(
+  void f() {
+    // CHECK-CXX17: call{{.*}} @_ZN7PR422201XC1Ev(
+    B &&b = {X()};
+    // CHECK-CXX17-NOT: call{{.*}} @_ZN7PR422201XD1Ev(
+    // CHECK-CXX17: call{{.*}} @_ZN7PR422201gEv(
+    g();
+    // CHECK-CXX17: call{{.*}} @_ZN7PR422201XD1Ev(
+  }
+}
+#endif
-- 
2.50.1