Index: include/clang/Basic/DiagnosticSemaKinds.td
===================================================================
--- include/clang/Basic/DiagnosticSemaKinds.td	(revision 157593)
+++ include/clang/Basic/DiagnosticSemaKinds.td	(working copy)
@@ -4322,10 +4322,6 @@
   def note_lambda_decl : Note<"lambda expression begins here">;
   def err_lambda_unevaluated_operand : Error<
     "lambda expression in an unevaluated operand">;
-  def ext_lambda_implies_void_return : ExtWarn<
-    "C++11 requires lambda with omitted result type to consist of a single "
-    "return statement">,
-    InGroup<LambdaExtensions>;
   def err_lambda_return_init_list : Error<
     "cannot deduce lambda return type from initializer list">;
   def err_lambda_capture_default_arg : Error<
Index: lib/Sema/SemaLambda.cpp
===================================================================
--- lib/Sema/SemaLambda.cpp	(revision 157593)
+++ lib/Sema/SemaLambda.cpp	(working copy)
@@ -648,26 +648,6 @@
       //     braced-init-list, the type void;
       if (LSI->ReturnType.isNull()) {
         LSI->ReturnType = Context.VoidTy;
-      } else {
-        // C++11 [expr.prim.lambda]p4:
-        //   - if the compound-statement is of the form
-        //
-        //       { attribute-specifier-seq[opt] return expression ; }
-        //
-        //     the type of the returned expression after
-        //     lvalue-to-rvalue conversion (4.1), array-to-pointer
-        //     conver- sion (4.2), and function-to-pointer conversion
-        //     (4.3);
-        //
-        // Since we're accepting the resolution to a post-C++11 core
-        // issue with a non-trivial extension, provide a warning (by
-        // default).
-        CompoundStmt *CompoundBody = cast<CompoundStmt>(Body);
-        if (!(CompoundBody->size() == 1 &&
-              isa<ReturnStmt>(*CompoundBody->body_begin())) &&
-            !Context.hasSameType(LSI->ReturnType, Context.VoidTy))
-          Diag(IntroducerRange.getBegin(), 
-               diag::ext_lambda_implies_void_return);
       }
 
       // Create a function type with the inferred return type.
Index: test/SemaCXX/uninitialized.cpp
===================================================================
--- test/SemaCXX/uninitialized.cpp	(revision 157593)
+++ test/SemaCXX/uninitialized.cpp	(working copy)
@@ -210,6 +210,6 @@
 
 // Test lambda expressions with -Wuninitialized
 int test_lambda() {
-  auto f1 = [] (int x, int y) { int z; return x + y + z; }; // expected-warning {{C++11 requires lambda with omitted result type to consist of a single return statement}} expected-warning{{variable 'z' is uninitialized when used here}} expected-note {{initialize the variable 'z' to silence this warning}}
+  auto f1 = [] (int x, int y) { int z; return x + y + z; }; // expected-warning{{variable 'z' is uninitialized when used here}} expected-note {{initialize the variable 'z' to silence this warning}}
   return f1(1, 2);
 }