Add an errc::make_error_code overload taking a source location

test/errc_test4.cpp

@@ -0,0 +1,17 @@
+// Copyright 2022 Peter Dimov.
+// Distributed under the Boost Software License, Version 1.0.
+// http://www.boost.org/LICENSE_1_0.txt
+
+#include <boost/system/errc.hpp>
+#include <boost/assert/source_location.hpp>
+#include <boost/core/lightweight_test.hpp>
+
+int main()
+{
+    BOOST_STATIC_CONSTEXPR boost::source_location loc = BOOST_CURRENT_LOCATION;
+
+    BOOST_TEST( make_error_code( boost::system::errc::no_such_file_or_directory, &loc ).has_location() );
+    BOOST_TEST_EQ( make_error_code( boost::system::errc::no_such_file_or_directory, &loc ).location().to_string(), loc.to_string() );
+
+    return boost::report_errors();
+}