[c++2a] Implement P0409R2 - Allow lambda capture [=,this] (by hamzasood)

This patch, by hamzasood, implements P0409R2, and allows [=, this] pre-C++2a as an extension (with appropriate warnings) for consistency.

https://reviews.llvm.org/D36572

Thanks Hamza!

llvm-svn: 311224

1 files changed, 15 insertions, 0 deletions

diff --git a/clang/test/SemaCXX/cxx2a-lambda-equals-this.cpp b/clang/test/SemaCXX/cxx2a-lambda-equals-this.cpp
new file mode 100644
index 00000000000..ce6916322e5
--- /dev/null
+++ b/clang/test/SemaCXX/cxx2a-lambda-equals-this.cpp
@@ -0,0 +1,15 @@
+// RUN: %clang_cc1 -std=c++2a -verify %s
+// expected-no-diagnostics
+
+// This test does two things.
+// Deleting the copy constructor ensures that an [=, this] capture doesn't copy the object.
+// Accessing a member variable from the lambda ensures that the capture actually works.
+class A {
+  A(const A &) = delete;
+  int i;
+
+  void func() {
+    auto L = [=, this]() -> int { return i; };
+    L();
+  }
+};