Fix nodiscard and constexpr

Author: rolandreichweinbmw

include/etl/span.h

@@ -408,7 +408,7 @@ namespace etl
     /// Reinterpret the span as a span with different element type.
     //*************************************************************************
     template<typename TNew>
-    ETL_NODISCARD ETL_CONSTEXPR etl::span<TNew, etl::dynamic_extent> reinterpret_as() const
+    ETL_NODISCARD ETL_CONSTEXPR14 etl::span<TNew, etl::dynamic_extent> reinterpret_as() const
     {
 #if ETL_USING_CPP11
       ETL_ASSERT(etl::is_aligned<alignof(TNew)>(pbegin), ETL_ERROR(span_alignment_exception));
@@ -752,7 +752,7 @@ namespace etl
     /// Reinterpret the span as a span with different element type.
     //*************************************************************************
     template<typename TNew>
-    ETL_NODISCARD ETL_CONSTEXPR etl::span<TNew, etl::dynamic_extent> reinterpret_as() const
+    ETL_NODISCARD ETL_CONSTEXPR14 etl::span<TNew, etl::dynamic_extent> reinterpret_as() const
     {
 #if ETL_USING_CPP11
       ETL_ASSERT(etl::is_aligned<alignof(TNew)>(pbegin), ETL_ERROR(span_alignment_exception));

test/test_span_dynamic_extent.cpp

@@ -1271,7 +1271,7 @@ namespace
       etl::span<uint16_t> data2 = data1.subspan(2).reinterpret_as<uint16_t>();
       CHECK_EQUAL(data2.size(), 5);
 
-      CHECK_THROW(data1.subspan(1).reinterpret_as<uint16_t>(), etl::span_alignment_exception);
+      CHECK_THROW(data2 = data1.subspan(1).reinterpret_as<uint16_t>(), etl::span_alignment_exception);
     }
 
     //*************************************************************************

test/test_span_fixed_extent.cpp

@@ -1150,7 +1150,7 @@ namespace
       etl::span<uint16_t> data2 = data1.subspan(2).reinterpret_as<uint16_t>();
       CHECK_EQUAL(data2.size(), 5);
 
-      CHECK_THROW(data1.subspan(1).reinterpret_as<uint16_t>(), etl::span_alignment_exception);
+      CHECK_THROW(data2 = data1.subspan(1).reinterpret_as<uint16_t>(), etl::span_alignment_exception);
     }
 
     //*************************************************************************