Features: Record the oldest supported compiler.

This may be used to ensure that features are reported correctly
only if the compiler minimum version is met.

1 files changed, 9 insertions, 10 deletions

diff --git a/Modules/Compiler/GNU-CXX-FeatureTests.cmake b/Modules/Compiler/GNU-CXX-FeatureTests.cmake
index 5edb69e..7be4657 100644
--- a/Modules/Compiler/GNU-CXX-FeatureTests.cmake
+++ b/Modules/Compiler/GNU-CXX-FeatureTests.cmake
@@ -1,7 +1,7 @@
 
 # Reference: http://gcc.gnu.org/projects/cxx0x.html
 
-set(_oldestSupported "(__GNUC__ * 100 + __GNUC_MINOR__) >= 407")
+set(_cmake_oldestSupported "(__GNUC__ * 100 + __GNUC_MINOR__) >= 407")
 # Introduced in GCC 4.8.1
 set(GNU481_CXX11 "((__GNUC__ * 100 + __GNUC_MINOR__) >= 408 && __GNUC_PATCHLEVEL__ >= 1) && __cplusplus >= 201103L")
 set(_cmake_feature_test_cxx_decltype_incomplete_return_types "${GNU481_CXX11}")
@@ -27,7 +27,7 @@ set(_cmake_feature_test_cxx_user_literals "${GNU47_CXX11}")
 # experiemental and possibly incomplete (see for example the note below about
 # cxx_variadic_template_template_parameters)
 # TODO: Should be supported by GNU 4.6
-set(GNU46_CXX11 "${_oldestSupported} && __cplusplus >= 201103L")
+set(GNU46_CXX11 "${_cmake_oldestSupported} && __cplusplus >= 201103L")
 set(_cmake_feature_test_cxx_constexpr "${GNU46_CXX11}")
 set(_cmake_feature_test_cxx_defaulted_move_initializers "${GNU46_CXX11}")
 set(_cmake_feature_test_cxx_enum_forward_declarations "${GNU46_CXX11}")
@@ -35,13 +35,13 @@ set(_cmake_feature_test_cxx_nullptr "${GNU46_CXX11}")
 set(_cmake_feature_test_cxx_range_for "${GNU46_CXX11}")
 set(_cmake_feature_test_cxx_unrestricted_unions "${GNU46_CXX11}")
 # TODO: Should be supported by GNU 4.5
-set(GNU45_CXX11 "${_oldestSupported} && __cplusplus >= 201103L")
+set(GNU45_CXX11 "${_cmake_oldestSupported} && __cplusplus >= 201103L")
 set(_cmake_feature_test_cxx_explicit_conversions "${GNU45_CXX11}")
 set(_cmake_feature_test_cxx_lambdas "${GNU45_CXX11}")
 set(_cmake_feature_test_cxx_local_type_template_args "${GNU45_CXX11}")
 set(_cmake_feature_test_cxx_raw_string_literals "${GNU45_CXX11}")
 # TODO: Should be supported by GNU 4.4
-set(GNU44_CXX11 "${_oldestSupported} && __cplusplus >= 201103L")
+set(GNU44_CXX11 "${_cmake_oldestSupported} && __cplusplus >= 201103L")
 set(_cmake_feature_test_cxx_auto_type "${GNU44_CXX11}")
 set(_cmake_feature_test_cxx_defaulted_functions "${GNU44_CXX11}")
 set(_cmake_feature_test_cxx_deleted_functions "${GNU44_CXX11}")
@@ -61,7 +61,7 @@ set(_cmake_feature_test_cxx_variadic_templates "${GNU44_CXX11}")
 # templates capability in CMake. See
 # http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2008/n2555.pdf
 # TODO: Should be supported by GNU 4.3
-set(GNU43_CXX11 "${_oldestSupported} && __cplusplus >= 201103L")
+set(GNU43_CXX11 "${_cmake_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 "${GNU43_CXX11}")
@@ -69,9 +69,8 @@ set(_cmake_feature_test_cxx_right_angle_brackets "${GNU43_CXX11}")
 set(_cmake_feature_test_cxx_rvalue_references "${GNU43_CXX11}")
 set(_cmake_feature_test_cxx_static_assert "${GNU43_CXX11}")
 # TODO: Should be supported since GNU 3.4?
-set(_cmake_feature_test_cxx_extern_templates "${_oldestSupported} && __cplusplus >= 201103L")
+set(_cmake_feature_test_cxx_extern_templates "${_cmake_oldestSupported} && __cplusplus >= 201103L")
 # TODO: Should be supported forever?
-set(_cmake_feature_test_cxx_func_identifier "${_oldestSupported} && __cplusplus >= 201103L")
-set(_cmake_feature_test_cxx_variadic_macros "${_oldestSupported} && __cplusplus >= 201103L")
-set(_cmake_feature_test_cxx_template_template_parameters "${_oldestSupported} && __cplusplus >= 199711L")
-set(_oldestSupported)
+set(_cmake_feature_test_cxx_func_identifier "${_cmake_oldestSupported} && __cplusplus >= 201103L")
+set(_cmake_feature_test_cxx_variadic_macros "${_cmake_oldestSupported} && __cplusplus >= 201103L")
+set(_cmake_feature_test_cxx_template_template_parameters "${_cmake_oldestSupported} && __cplusplus >= 199711L")