Features: Add cxx_long_long_type.

Help/variable/CMAKE_CXX_KNOWN_FEATURES.rst

@@ -127,6 +127,11 @@ The features known to this version of CMake are:
 
   .. _N2657: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2657.htm
 
+``cxx_long_long_type``
+  ``long long`` type, as defined in N1811_.
+
+  .. _N1811: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2005/n1811.pdf
+
 ``cxx_noexcept``
   Exception specifications, as defined in N3050_.
 

Modules/Compiler/GNU-CXX-FeatureTests.cmake

@@ -64,6 +64,7 @@ set(_cmake_feature_test_cxx_variadic_templates "${GNU44_CXX11}")
 set(GNU43_CXX11 "${_oldestSupported} && __cplusplus >= 201103L")
 set(_cmake_feature_test_cxx_decltype "${GNU43_CXX11}")
 set(_cmake_feature_test_cxx_default_function_template_args "${GNU43_CXX11}")
+set(_cmake_feature_test_cxx_long_long_type "${GNU43_CXX11}")
 set(_cmake_feature_test_cxx_right_angle_brackets "${GNU43_CXX11}")
 set(_cmake_feature_test_cxx_rvalue_references "${GNU43_CXX11}")
 set(_cmake_feature_test_cxx_static_assert "${GNU43_CXX11}")

Source/cmMakefile.cxx

@@ -65,6 +65,7 @@
   F(cxx_inline_namespaces) \
   F(cxx_lambdas) \
   F(cxx_local_type_template_args) \
+  F(cxx_long_long_type) \
   F(cxx_noexcept) \
   F(cxx_nonstatic_member_init) \
   F(cxx_nullptr) \

Tests/CompileFeatures/cxx_long_long_type.cpp

@@ -0,0 +1,5 @@
+
+void someFunc()
+{
+  long long ll = 9223372036854775807LL;
+}