diff --git a/include/etl/private/delegate_cpp11.h b/include/etl/private/delegate_cpp11.h
index 8f438602..c58adc42 100644
--- a/include/etl/private/delegate_cpp11.h
+++ b/include/etl/private/delegate_cpp11.h
@@ -126,6 +126,12 @@ namespace etl
       assign((void*)(&instance), const_lambda_stub<TLambda>);
     }
 
+    //*************************************************************************
+    // Delete construction from rvalue reference lambda or functor.
+    //*************************************************************************
+    template <typename TLambda, typename = etl::enable_if_t<etl::is_class<TLambda>::value && !etl::is_same<etl::delegate<TReturn(TParams...)>, TLambda>::value, void>>
+    ETL_CONSTEXPR14 delegate(TLambda&& instance) = delete;
+
     //*************************************************************************
     /// Create from function (Compile time).
     //*************************************************************************
diff --git a/test/test_base64_RFC2152_decoder.cpp b/test/test_base64_RFC2152_decoder.cpp
index 2428095e..64cc11ca 100644
--- a/test/test_base64_RFC2152_decoder.cpp
+++ b/test/test_base64_RFC2152_decoder.cpp
@@ -64,7 +64,7 @@ namespace
   std::vector<unsigned char> decoded_output;
   bool received_final_block = false;
 
-  codec::callback_type callback = [](const codec::span_type& sp)
+  auto lambda = [](const codec::span_type& sp)
     {
       if (sp.empty())
       {
@@ -76,6 +76,8 @@ namespace
       }
     };
 
+  codec::callback_type callback = lambda;
+
   std::array<unsigned char, 256> input_data =
   {
     0x3B, 0x27, 0x03, 0x43, 0x2D, 0xFB, 0x28, 0x2A, 0x61, 0xAE, 0xBC, 0x49, 0x71, 0x32, 0x01, 0x15,
diff --git a/test/test_base64_RFC2152_encoder.cpp b/test/test_base64_RFC2152_encoder.cpp
index bd4c2b13..f463da39 100644
--- a/test/test_base64_RFC2152_encoder.cpp
+++ b/test/test_base64_RFC2152_encoder.cpp
@@ -62,7 +62,7 @@ namespace
   std::string encoded_output;
   bool received_final_block = false;
 
-  codec::callback_type callback = [](const codec::span_type& sp)
+  auto lambda = [](const codec::span_type& sp)
     {
       if (sp.empty())
       {
@@ -74,6 +74,8 @@ namespace
       }
     };
 
+  codec::callback_type callback = lambda;
+
   std::array<unsigned char, 256> input_data =
   {
     0x3B, 0x27, 0x03, 0x43, 0x2D, 0xFB, 0x28, 0x2A, 0x61, 0xAE, 0xBC, 0x49, 0x71, 0x32, 0x01, 0x15,
diff --git a/test/test_base64_RFC3501_decoder.cpp b/test/test_base64_RFC3501_decoder.cpp
index 60915724..2e3c2faf 100644
--- a/test/test_base64_RFC3501_decoder.cpp
+++ b/test/test_base64_RFC3501_decoder.cpp
@@ -61,7 +61,7 @@ namespace
   std::vector<unsigned char> decoded_output;
   bool received_final_block = false;
 
-  codec::callback_type callback = [](const codec::span_type& sp)
+  auto lambda = [](const codec::span_type& sp)
     {
       if (sp.empty())
       {
@@ -73,6 +73,8 @@ namespace
       }
     };
 
+  codec::callback_type callback = lambda;
+
   std::array<unsigned char, 256> input_data =
   {
     0x3B, 0x27, 0x03, 0x43, 0x2D, 0xFB, 0x28, 0x2A, 0x61, 0xAE, 0xBC, 0x49, 0x71, 0x32, 0x01, 0x15,
diff --git a/test/test_base64_RFC3501_encoder.cpp b/test/test_base64_RFC3501_encoder.cpp
index de54cbe6..0acc36a3 100644
--- a/test/test_base64_RFC3501_encoder.cpp
+++ b/test/test_base64_RFC3501_encoder.cpp
@@ -62,7 +62,7 @@ namespace
   std::string encoded_output;
   bool received_final_block = false;
 
-  codec::callback_type callback = [](const codec::span_type& sp)
+  auto lambda = [](const codec::span_type& sp)
     {
       if (sp.empty())
       {
@@ -74,6 +74,8 @@ namespace
       }
     };
 
+  codec::callback_type callback = lambda;
+
   std::array<unsigned char, 256> input_data =
   {
     0x3B, 0x27, 0x03, 0x43, 0x2D, 0xFB, 0x28, 0x2A, 0x61, 0xAE, 0xBC, 0x49, 0x71, 0x32, 0x01, 0x15,
diff --git a/test/test_base64_RFC4648_URL_decoder_with_no_padding.cpp b/test/test_base64_RFC4648_URL_decoder_with_no_padding.cpp
index bf8e177e..c1c9280d 100644
--- a/test/test_base64_RFC4648_URL_decoder_with_no_padding.cpp
+++ b/test/test_base64_RFC4648_URL_decoder_with_no_padding.cpp
@@ -61,7 +61,7 @@ namespace
   std::vector<unsigned char> decoded_output;
   bool received_final_block = false;
 
-  codec::callback_type callback = [](const codec::span_type& sp)
+  auto lambda = [](const codec::span_type& sp)
     {
       if (sp.empty())
       {
@@ -73,6 +73,8 @@ namespace
       }
     };
 
+  codec::callback_type callback = lambda;
+
   std::array<unsigned char, 256> input_data =
   {
     0x3B, 0x27, 0x03, 0x43, 0x2D, 0xFB, 0x28, 0x2A, 0x61, 0xAE, 0xBC, 0x49, 0x71, 0x32, 0x01, 0x15,
diff --git a/test/test_base64_RFC4648_URL_decoder_with_padding.cpp b/test/test_base64_RFC4648_URL_decoder_with_padding.cpp
index 96bd3c74..ab75c182 100644
--- a/test/test_base64_RFC4648_URL_decoder_with_padding.cpp
+++ b/test/test_base64_RFC4648_URL_decoder_with_padding.cpp
@@ -61,7 +61,7 @@ namespace
   std::vector<unsigned char> decoded_output;
   bool received_final_block = false;
 
-  codec::callback_type callback = [](const codec::span_type& sp)
+  auto lambda = [](const codec::span_type& sp)
     {
       if (sp.empty())
       {
@@ -73,6 +73,8 @@ namespace
       }
     };
 
+  codec::callback_type callback = lambda;
+
   std::array<unsigned char, 256> input_data =
   {
     0x3B, 0x27, 0x03, 0x43, 0x2D, 0xFB, 0x28, 0x2A, 0x61, 0xAE, 0xBC, 0x49, 0x71, 0x32, 0x01, 0x15,
diff --git a/test/test_base64_RFC4648_URL_encoder_with_no_padding.cpp b/test/test_base64_RFC4648_URL_encoder_with_no_padding.cpp
index 0b97f8c9..56835228 100644
--- a/test/test_base64_RFC4648_URL_encoder_with_no_padding.cpp
+++ b/test/test_base64_RFC4648_URL_encoder_with_no_padding.cpp
@@ -62,7 +62,7 @@ namespace
   std::string encoded_output;
   bool received_final_block = false;
 
-  codec::callback_type callback = [](const codec::span_type& sp)
+  auto lambda = [](const codec::span_type& sp)
     {
       if (sp.empty())
       {
@@ -74,6 +74,8 @@ namespace
       }
     };
 
+  codec::callback_type callback = lambda;
+
   std::array<unsigned char, 256> input_data =
   {
     0x3B, 0x27, 0x03, 0x43, 0x2D, 0xFB, 0x28, 0x2A, 0x61, 0xAE, 0xBC, 0x49, 0x71, 0x32, 0x01, 0x15,
diff --git a/test/test_base64_RFC4648_URL_encoder_with_padding.cpp b/test/test_base64_RFC4648_URL_encoder_with_padding.cpp
index 90a95527..9c9f2e21 100644
--- a/test/test_base64_RFC4648_URL_encoder_with_padding.cpp
+++ b/test/test_base64_RFC4648_URL_encoder_with_padding.cpp
@@ -62,7 +62,7 @@ namespace
   std::string encoded_output;
   bool received_final_block = false;
 
-  codec::callback_type callback = [](const codec::span_type& sp)
+  auto lambda = [](const codec::span_type& sp)
     {
       if (sp.empty())
       {
@@ -74,6 +74,8 @@ namespace
       }
     };
 
+  codec::callback_type callback = lambda;
+
   std::array<unsigned char, 256> input_data =
   {
     0x3B, 0x27, 0x03, 0x43, 0x2D, 0xFB, 0x28, 0x2A, 0x61, 0xAE, 0xBC, 0x49, 0x71, 0x32, 0x01, 0x15,
diff --git a/test/test_base64_RFC4648_decoder_with_no_padding.cpp b/test/test_base64_RFC4648_decoder_with_no_padding.cpp
index ea21ebcc..8fbde338 100644
--- a/test/test_base64_RFC4648_decoder_with_no_padding.cpp
+++ b/test/test_base64_RFC4648_decoder_with_no_padding.cpp
@@ -61,7 +61,7 @@ namespace
   std::vector<unsigned char> decoded_output;
   bool received_final_block = false;
 
-  codec::callback_type callback = [](const codec::span_type& sp)
+  auto lambda = [](const codec::span_type& sp)
     {
       if (sp.empty())
       {
@@ -73,6 +73,8 @@ namespace
       }
     };
 
+  codec::callback_type callback = lambda;
+
   std::array<unsigned char, 256> input_data =
   {
     0x3B, 0x27, 0x03, 0x43, 0x2D, 0xFB, 0x28, 0x2A, 0x61, 0xAE, 0xBC, 0x49, 0x71, 0x32, 0x01, 0x15,
diff --git a/test/test_base64_RFC4648_decoder_with_padding.cpp b/test/test_base64_RFC4648_decoder_with_padding.cpp
index 6d910ecd..fef5112a 100644
--- a/test/test_base64_RFC4648_decoder_with_padding.cpp
+++ b/test/test_base64_RFC4648_decoder_with_padding.cpp
@@ -61,7 +61,7 @@ namespace
   std::vector<unsigned char> decoded_output;
   bool received_final_block = false;
 
-  codec::callback_type callback = [](const codec::span_type& sp)
+  auto lambda = [](const codec::span_type& sp)
     {
       if (sp.empty())
       {
@@ -73,6 +73,8 @@ namespace
       }
     };
 
+  codec::callback_type callback = lambda;
+
   std::array<unsigned char, 256> input_data =
   {
     0x3B, 0x27, 0x03, 0x43, 0x2D, 0xFB, 0x28, 0x2A, 0x61, 0xAE, 0xBC, 0x49, 0x71, 0x32, 0x01, 0x15,
diff --git a/test/test_base64_RFC4648_encoder_with_no_padding.cpp b/test/test_base64_RFC4648_encoder_with_no_padding.cpp
index 2d964d80..eefe003f 100644
--- a/test/test_base64_RFC4648_encoder_with_no_padding.cpp
+++ b/test/test_base64_RFC4648_encoder_with_no_padding.cpp
@@ -62,7 +62,7 @@ namespace
   std::string encoded_output;
   bool received_final_block = false;
 
-  codec::callback_type callback = [](const codec::span_type& sp)
+  auto lambda = [](const codec::span_type& sp)
     {
       if (sp.empty())
       {
@@ -74,6 +74,8 @@ namespace
       }
     };
 
+  codec::callback_type callback = lambda;
+
   std::array<unsigned char, 256> input_data =
   {
     0x3B, 0x27, 0x03, 0x43, 0x2D, 0xFB, 0x28, 0x2A, 0x61, 0xAE, 0xBC, 0x49, 0x71, 0x32, 0x01, 0x15,
diff --git a/test/test_base64_RFC4648_encoder_with_padding.cpp b/test/test_base64_RFC4648_encoder_with_padding.cpp
index 148b1fe4..50b48b3b 100644
--- a/test/test_base64_RFC4648_encoder_with_padding.cpp
+++ b/test/test_base64_RFC4648_encoder_with_padding.cpp
@@ -61,8 +61,8 @@ namespace
 
   std::string encoded_output;
   bool received_final_block = false;
-
-  codec::callback_type callback = [](const codec::span_type& sp)
+  
+  auto lambda = [](const codec::span_type& sp)
     {
       if (sp.empty())
       {
@@ -74,6 +74,8 @@ namespace
       }
     };
 
+  codec::callback_type callback = lambda;
+
   std::array<unsigned char, 256> input_data =
   {
     0x3B, 0x27, 0x03, 0x43, 0x2D, 0xFB, 0x28, 0x2A, 0x61, 0xAE, 0xBC, 0x49, 0x71, 0x32, 0x01, 0x15,
diff --git a/test/test_byte_stream.cpp b/test/test_byte_stream.cpp
index 13d4eaaa..4d63068d 100644
--- a/test/test_byte_stream.cpp
+++ b/test/test_byte_stream.cpp
@@ -1318,10 +1318,12 @@ namespace
 
       static std::vector<char> result;
 
-      etl::byte_stream_writer::callback_type callback([&](etl::byte_stream_writer::callback_parameter_type sp) 
-                                                      { 
-                                                        std::copy(sp.begin(), sp.end(), std::back_inserter(result));
-                                                      });
+      auto lambda = [&](etl::byte_stream_writer::callback_parameter_type sp) 
+        { 
+          std::copy(sp.begin(), sp.end(), std::back_inserter(result));
+        };
+
+      etl::byte_stream_writer::callback_type callback(lambda);
 
       etl::byte_stream_writer writer(storage.data(), storage.size(), etl::endian::big, callback);
 
diff --git a/test/test_delegate.cpp b/test/test_delegate.cpp
index 0f9d29a8..852627e7 100644
--- a/test/test_delegate.cpp
+++ b/test/test_delegate.cpp
@@ -287,7 +287,9 @@ namespace
     //*************************************************************************
     TEST_FIXTURE(SetupFixture, test_is_valid_true)
     {
-      etl::delegate<void(void)> d([] {});
+      auto lambda = [] {};
+
+      etl::delegate<void(void)> d(lambda);
 
       CHECK(d.is_valid());
       CHECK(d);
@@ -297,7 +299,9 @@ namespace
     //*************************************************************************
     TEST_FIXTURE(SetupFixture, test_is_valid_after_clear)
     {
-      etl::delegate<void(void)> d([] {});
+      auto lambda = [] {};
+
+      etl::delegate<void(void)> d(lambda);
 
       CHECK_TRUE(d.is_valid());
       d.clear();
@@ -413,7 +417,9 @@ namespace
     //*************************************************************************
     TEST_FIXTURE(SetupFixture, test_lambda_int)
     {
-      etl::delegate<void(int, int)> d([](int i, int j) { function_called = FunctionCalled::Lambda_Called; parameter_correct = (i == VALUE1) && (j == VALUE2); });
+      auto lambda = [](int i, int j) { function_called = FunctionCalled::Lambda_Called; parameter_correct = (i == VALUE1) && (j == VALUE2); };
+
+      etl::delegate<void(int, int)> d(lambda);
 
       d(VALUE1, VALUE2);