PR24164, PR39336: init-captures are not distinct full-expressions.

Rather, they are subexpressions of the enclosing lambda-expression, and
any temporaries in them are destroyed at the end of that
full-expression, or when the corresponding lambda-expression is
destroyed if they are lifetime-extended.

llvm-svn: 344801

3 files changed, 68 insertions, 5 deletions

diff --git a/clang/test/CXX/special/class.temporary/p6.cpp b/clang/test/CXX/special/class.temporary/p6.cpp
index e8680902165..077385fb7aa 100644
--- a/clang/test/CXX/special/class.temporary/p6.cpp
+++ b/clang/test/CXX/special/class.temporary/p6.cpp
@@ -1,4 +1,15 @@
-// RUN: %clang_cc1 -std=c++17 %s -emit-llvm -o - | FileCheck %s --implicit-check-not='call{{.*}}dtor'
+// RUN: %clang_cc1 -std=c++17 %s -triple x86_64-linux-gnu -emit-llvm -o - | FileCheck %s --implicit-check-not='call{{.*}}dtor'
+
+namespace std {
+  typedef decltype(sizeof(int)) size_t;
+
+  template <class E>
+  struct initializer_list {
+    const E *begin;
+    size_t   size;
+    initializer_list() : begin(nullptr), size(0) {}
+  };
+}
 
 void then();
 
@@ -8,6 +19,14 @@ struct dtor {
 
 dtor ctor();
 
+auto &&lambda = [a = {ctor()}] {};
+// CHECK-LABEL: define
+// CHECK: call {{.*}}ctor
+// CHECK: call {{.*}}atexit{{.*}}global_array_dtor
+
+// CHECK-LABEL: define{{.*}}global_array_dtor
+// CHECK: call {{.*}}dtor
+
 // [lifetime extension occurs if the object was obtained by]
 //  -- a temporary materialization conversion
 // CHECK-LABEL: ref_binding
@@ -188,3 +207,34 @@ void comma() {
   // CHECK: call {{.*}}dtor
   // CHECK: }
 }
+
+
+// This applies recursively: if an object is lifetime-extended and contains a
+// reference, the referent is also extended.
+// CHECK-LABEL: init_capture_ref
+void init_capture_ref() {
+  // CHECK: call {{.*}}ctor
+  auto x = [&a = (const dtor&)ctor()] {};
+  // CHECK: call {{.*}}then
+  then();
+  // CHECK: call {{.*}}dtor
+  // CHECK: }
+}
+// CHECK-LABEL: init_capture_ref_indirect
+void init_capture_ref_indirect() {
+  // CHECK: call {{.*}}ctor
+  auto x = [&a = (const dtor&)ctor()] {};
+  // CHECK: call {{.*}}then
+  then();
+  // CHECK: call {{.*}}dtor
+  // CHECK: }
+}
+// CHECK-LABEL: init_capture_init_list
+void init_capture_init_list() {
+  // CHECK: call {{.*}}ctor
+  auto x = [a = {ctor()}] {};
+  // CHECK: call {{.*}}then
+  then();
+  // CHECK: call {{.*}}dtor
+  // CHECK: }
+}
diff --git a/clang/test/CodeGenCXX/cxx1y-init-captures.cpp b/clang/test/CodeGenCXX/cxx1y-init-captures.cpp
index dcfe4d47292..c76180c5bf4 100644
--- a/clang/test/CodeGenCXX/cxx1y-init-captures.cpp
+++ b/clang/test/CodeGenCXX/cxx1y-init-captures.cpp
@@ -38,6 +38,19 @@ void g() {
 
 // CHECK: add nsw i32
 
+// CHECK-LABEL: define void @_Z18init_capture_dtorsv
+void init_capture_dtors() {
+  // Ensure that init-captures are not treated as separate full-expressions.
+  struct HasDtor { ~HasDtor() {} };
+  void some_function_call();
+  void other_function_call();
+  // CHECK: call {{.*}}some_function_call
+  // CHECK: call {{.*}}HasDtorD
+  ([x = (HasDtor(), 0)]{}, some_function_call());
+  // CHECK: call {{.*}}other_function_call
+  other_function_call();
+}
+
 int h(int a) {
   // CHECK-LABEL: define i32 @_Z1hi(
   // CHECK: %[[A_ADDR:.*]] = alloca i32,
diff --git a/clang/test/SemaCXX/cxx1y-init-captures.cpp b/clang/test/SemaCXX/cxx1y-init-captures.cpp
index 4b82452ed59..16cffb2a914 100644
--- a/clang/test/SemaCXX/cxx1y-init-captures.cpp
+++ b/clang/test/SemaCXX/cxx1y-init-captures.cpp
@@ -144,13 +144,13 @@ int test(T t = T{}) {
     };
   }
   { // will need to capture x in outer lambda
-    const int x = 10; //expected-note 2{{declared}}
-    auto L = [z = x](char a) { //expected-note 2{{begins}}
-      auto M = [&y = x](T b) { //expected-error 2{{cannot be implicitly captured}}
+    const int x = 10; //expected-note {{declared}}
+    auto L = [z = x](char a) { //expected-note {{begins}}
+      auto M = [&y = x](T b) { //expected-error {{cannot be implicitly captured}}
         return y;
       };
       return M;
-    };     
+    };
   }
   {
     // no captures