Do not try to perform lifetime-extension through conditional

expressions.

CodeGen can't cope with that yet. Instead, produce a "not supported"
warning for now and don't extend lifetime.

llvm-svn: 337744

1 files changed, 21 insertions, 1 deletions

diff --git a/clang/test/SemaCXX/conditional-expr.cpp b/clang/test/SemaCXX/conditional-expr.cpp
index 7e6b0ce8e8f..ab19ce54b69 100644
--- a/clang/test/SemaCXX/conditional-expr.cpp
+++ b/clang/test/SemaCXX/conditional-expr.cpp
@@ -1,4 +1,5 @@
 // RUN: %clang_cc1 -fcxx-exceptions -fexceptions -fsyntax-only -verify -std=c++11 -Wsign-conversion %s
+// RUN: %clang_cc1 -fcxx-exceptions -fexceptions -fsyntax-only -verify -std=c++17 -Wsign-conversion %s
 
 // C++ rules for ?: are a lot stricter than C rules, and have to take into
 // account more conversion options.
@@ -228,7 +229,7 @@ void test()
   // be properly tested at runtime, though.
 
   const Abstract &abstract1 = true ? static_cast<const Abstract&>(Derived1()) : Derived2(); // expected-error {{allocating an object of abstract class type 'const Abstract'}}
-  const Abstract &abstract2 = true ? static_cast<const Abstract&>(Derived1()) : throw 3; // ok
+  const Abstract &abstract2 = true ? static_cast<const Abstract&>(Derived1()) : throw 3; // expected-warning-re {{sorry, lifetime extension {{.*}} not supported}}
 }
 
 namespace PR6595 {
@@ -393,3 +394,22 @@ Derived d;
 typedef decltype(true ? static_cast<Base&&>(b) : static_cast<Derived&&>(d)) x;
 typedef Base &&x;
 }
+
+namespace lifetime_extension {
+  struct A {};
+  struct B : A { B(); ~B(); };
+  struct C : A { C(); ~C(); };
+
+  void f(bool b) {
+    // expected-warning@+1 2{{sorry, lifetime extension of temporary created within conditional expression is not supported}}
+    A &&r = b ? static_cast<A&&>(B()) : static_cast<A&&>(C());
+  }
+
+  struct D { A &&a; };
+  void f_indirect(bool b) {
+#if __cplusplus >= 201702L
+    // expected-warning@+2 2{{sorry, lifetime extension of temporary created within conditional expression is not supported}}
+#endif
+    D d = b ? D{B()} : D{C()};
+  }
+}