Fix computation of linkage within nested lambdas.

When nested C++11 lambdas are used in NSDMI's - this patch prevents infinite recursion by computing the linkage of any nested lambda by determining the linkage of the outermost enclosing lambda (which might inherit its linkage from its parent).

See http://llvm-reviews.chandlerc.com/D1783 for Doug's approval.

[On a related note, I need this patch so as to pass tests of transformations of nested lambdas returned from member functions]

llvm-svn: 191727

1 files changed, 50 insertions, 0 deletions

diff --git a/clang/test/CodeGenCXX/lambda-expressions-nested-linkage.cpp b/clang/test/CodeGenCXX/lambda-expressions-nested-linkage.cpp
new file mode 100644
index 00000000000..accc5d2c4c3
--- /dev/null
+++ b/clang/test/CodeGenCXX/lambda-expressions-nested-linkage.cpp
@@ -0,0 +1,50 @@
+// RUN: %clang_cc1 -triple x86_64-apple-darwin10.0.0 -fblocks -emit-llvm -o - %s -fexceptions -std=c++11 | FileCheck %s
+
+// CHECK-LABEL: define void @_ZN19non_inline_function3fooEv()
+// CHECK-LABEL: define internal void @"_ZZN19non_inline_function3fooEvENK3$_0clEi"(%class.anon
+// CHECK-LABEL: define internal signext i8 @"_ZZZN19non_inline_function3fooEvENK3$_0clEiENKUlcE_clEc"(%class.anon
+namespace non_inline_function {
+void foo() {
+  auto L = [](int a) {
+    return [](char b) {
+     return b;
+    };
+  };
+  L(3)('a');
+}
+}
+
+namespace non_template {
+  struct L {
+    int t = ([](int a) { return [](int b) { return b; };})(2)(3);    
+  };
+  L l; 
+}
+
+namespace lambdas_in_NSDMIs_template_class {
+template<class T>
+struct L {
+    T t2 = ([](int a) { return [](int b) { return b; };})(T{})(T{});    
+};
+L<int> l;
+}
+
+// CHECK-LABEL: define linkonce_odr i32 @_ZN15inline_function3fooEv
+// CHECK: define linkonce_odr void @_ZZN15inline_function3fooEvENKUliE_clEi
+// CHECK: define linkonce_odr signext i8 @_ZZZN15inline_function3fooEvENKUliE_clEiENKUlcE_clEc
+namespace inline_function {
+inline int foo() {
+  auto L = [](int a) {
+    return [](char b) {
+     return b;
+    };
+  };
+  L(3)('a');
+}
+int use = foo();
+}
+// CHECK: define linkonce_odr void @_ZNK32lambdas_in_NSDMIs_template_class1LIiEUliE_clEi(%class.anon
+// CHECK: define linkonce_odr i32 @_ZZNK32lambdas_in_NSDMIs_template_class1LIiEUliE_clEiENKUliE_clEi(%class.anon
+
+// CHECK: define linkonce_odr void @_ZNK12non_template1L1tMUliE_clEi(%class.anon
+// CHECK: define linkonce_odr i32 @_ZZNK12non_template1L1tMUliE_clEiENKUliE_clEi(%class.anon