Features: Add cxx_unicode_literals.

Help/variable/CMAKE_CXX_KNOWN_FEATURES.rst

@@ -122,6 +122,11 @@ The features known to this version of CMake are:
 
   .. _N2541: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2541.htm
 
+``cxx_unicode_literals``
+  Unicode string literals, as defined in N2442_.
+
+  .. _N2442: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2442.htm
+
 ``cxx_user_literals``
   User-defined literals, as defined in N2765_.
 

Modules/Compiler/GNU-CXX-FeatureTests.cmake

@@ -38,6 +38,7 @@ set(_cmake_feature_test_cxx_defaulted_functions "${GNU44_CXX11}")
 set(_cmake_feature_test_cxx_deleted_functions "${GNU44_CXX11}")
 set(_cmake_feature_test_cxx_strong_enums "${GNU44_CXX11}")
 set(_cmake_feature_test_cxx_trailing_return_types "${GNU44_CXX11}")
+set(_cmake_feature_test_cxx_unicode_literals "${GNU44_CXX11}")
 set(_cmake_feature_test_cxx_variadic_templates "${GNU44_CXX11}")
 # TODO: If features are ever recorded for GNU 4.3, there should possibly
 # be a new feature added like cxx_variadic_template_template_parameters,

Source/cmMakefile.cxx

@@ -64,6 +64,7 @@
   F(cxx_static_assert) \
   F(cxx_strong_enums) \
   F(cxx_trailing_return_types) \
+  F(cxx_unicode_literals) \
   F(cxx_user_literals) \
   F(cxx_variadic_templates)
 

Tests/CompileFeatures/cxx_unicode_literals.cpp

@@ -0,0 +1,3 @@
+
+const char16_t lit_16[] = u"\u00DA";
+const char32_t lit_32[] = U"\u00DA";