16 files changed, 105 insertions, 2 deletions
diff --git a/Help/variable/CMAKE_CXX_KNOWN_FEATURES.rst b/Help/variable/CMAKE_CXX_KNOWN_FEATURES.rst
index 7466d44..d49bb68 100644
--- a/Help/variable/CMAKE_CXX_KNOWN_FEATURES.rst
+++ b/Help/variable/CMAKE_CXX_KNOWN_FEATURES.rst
@@ -6,3 +6,10 @@ List of C++ features known to this version of CMake.
 The features listed in this variable may be known to be available to the
 C++ compiler.  If the feature is available with the C++ compiler, it will
 be listed in the :variable:`CMAKE_CXX_COMPILE_FEATURES` variable.
+
+The features known to this version of CMake are:
+
+``cxx_auto_type``
+  Automatic type deduction, as defined in N1984_.
+
+  .. _N1984: http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2006/n1984.pdf
diff --git a/Modules/Compiler/GNU-CXX-FeatureTests.cmake b/Modules/Compiler/GNU-CXX-FeatureTests.cmake
new file mode 100644
index 0000000..b36315f
--- /dev/null
+++ b/Modules/Compiler/GNU-CXX-FeatureTests.cmake
@@ -0,0 +1,8 @@
+
+# Reference: http://gcc.gnu.org/projects/cxx0x.html
+
+set(_oldestSupported "(__GNUC__ * 100 + __GNUC_MINOR__) >= 408")
+# TODO: Should be supported by GNU 4.4
+set(GNU44_CXX11 "${_oldestSupported} && __cplusplus >= 201103L")
+set(_cmake_feature_test_cxx_auto_type "${GNU44_CXX11}")
+set(_oldestSupported)
diff --git a/Modules/Compiler/GNU-CXX.cmake b/Modules/Compiler/GNU-CXX.cmake
index 3ee8639..7acad52 100644
--- a/Modules/Compiler/GNU-CXX.cmake
+++ b/Modules/Compiler/GNU-CXX.cmake
@@ -23,3 +23,15 @@ elseif(NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.3)
   set(CMAKE_CXX11_STANDARD_COMPILE_OPTION "-std=c++0x")
   set(CMAKE_CXX11_EXTENSION_COMPILE_OPTION "-std=gnu++0x")
 endif()
+
+macro(cmake_record_cxx_compile_features)
+  macro(_get_gcc_features std_version list)
+    record_compiler_features(CXX "-std=${std_version}" ${list})
+  endmacro()
+
+  if (UNIX AND NOT APPLE AND NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.8)
+    _get_gcc_features(c++11 CMAKE_CXX11_COMPILE_FEATURES)
+  else()
+    set(_result 0)
+  endif()
+endmacro()
diff --git a/Source/cmMakefile.cxx b/Source/cmMakefile.cxx
index 64163de..0b3c43e 100644
--- a/Source/cmMakefile.cxx
+++ b/Source/cmMakefile.cxx
@@ -41,7 +41,8 @@
 #include <ctype.h> // for isspace
 #include <assert.h>
 
-#define FOR_EACH_CXX_FEATURE(F)
+#define FOR_EACH_CXX_FEATURE(F) \
+  F(cxx_auto_type)
 
 class cmMakefile::Internals
 {
@@ -2453,6 +2454,12 @@ const char* cmMakefile::GetDefinition(const std::string& name) const
     {
     this->Internal->VarUsageStack.top().insert(name);
     }
+  if (name == "CMAKE_CXX_KNOWN_FEATURES")
+    {
+#define STRING_LIST_ELEMENT(F) ";" #F
+    return FOR_EACH_CXX_FEATURE(STRING_LIST_ELEMENT) + 1;
+#undef STRING_LIST_ELEMENT
+    }
   const char* def = this->Internal->VarStack.top().Get(name);
   if(!def)
     {
@@ -4520,7 +4527,15 @@ AddRequiredTargetFeature(cmTarget *target, const std::string& feature,
   if (!isCxxFeature)
     {
     cmOStringStream e;
-    e << "specified unknown feature \"" << feature << "\" specified for "
+    if (error)
+      {
+      e << "specified";
+      }
+    else
+      {
+      e << "Specified";
+      }
+    e << " unknown feature \"" << feature << "\" for "
       "target \"" << target->GetName() << "\".";
     if (error)
       {
diff --git a/Tests/CMakeLists.txt b/Tests/CMakeLists.txt
index aaa24c7..fc58f1e 100644
--- a/Tests/CMakeLists.txt
+++ b/Tests/CMakeLists.txt
@@ -197,6 +197,10 @@ if(BUILD_TESTING)
   ADD_TEST_MACRO(TarTest TarTest)
   ADD_TEST_MACRO(SystemInformation SystemInformation)
   ADD_TEST_MACRO(MathTest MathTest)
+  if(CMAKE_CXX_COMPILER_ID STREQUAL GNU
+      AND NOT CMAKE_CXX_COMPILER_VERSION VERSION_LESS 4.8)
+    ADD_TEST_MACRO(CompileFeatures CompileFeatures)
+  endif()
   # assume no resources building to test
   set(TEST_RESOURCES FALSE)
   # for windows and cygwin assume we have resources
diff --git a/Tests/CompileFeatures/CMakeLists.txt b/Tests/CompileFeatures/CMakeLists.txt
new file mode 100644
index 0000000..471b560
--- /dev/null
+++ b/Tests/CompileFeatures/CMakeLists.txt
@@ -0,0 +1,24 @@
+
+cmake_minimum_required(VERSION 3.0)
+
+project(CompileFeatures)
+
+macro(run_test feature)
+  if (";${CMAKE_CXX_COMPILE_FEATURES};" MATCHES ${feature})
+    add_library(test_${feature} OBJECT ${feature}.cpp)
+    set_property(TARGET test_${feature}
+      PROPERTY COMPILE_FEATURES "${feature}"
+    )
+  else()
+    message("Not supported: ${feature}")
+  endif()
+endmacro()
+
+foreach(feature ${CMAKE_CXX_KNOWN_FEATURES})
+  run_test(${feature})
+endforeach()
+
+add_executable(CompileFeatures main.cpp)
+set_property(TARGET CompileFeatures
+  PROPERTY COMPILE_FEATURES "cxx_auto_type"
+)
diff --git a/Tests/CompileFeatures/cxx_auto_type.cpp b/Tests/CompileFeatures/cxx_auto_type.cpp
new file mode 100644
index 0000000..7dbf04f
--- /dev/null
+++ b/Tests/CompileFeatures/cxx_auto_type.cpp
@@ -0,0 +1,5 @@
+
+void someFunc()
+{
+  auto x = 3.14;
+}
diff --git a/Tests/CompileFeatures/main.cpp b/Tests/CompileFeatures/main.cpp
new file mode 100644
index 0000000..3a8e0fc
--- /dev/null
+++ b/Tests/CompileFeatures/main.cpp
@@ -0,0 +1,6 @@
+
+int main(int,char**)
+{
+  auto value = 0;
+  return value;
+}
diff --git a/Tests/RunCMake/CMakeLists.txt b/Tests/RunCMake/CMakeLists.txt
index 851de42..dd769ac 100644
--- a/Tests/RunCMake/CMakeLists.txt
+++ b/Tests/RunCMake/CMakeLists.txt
@@ -53,6 +53,7 @@ add_RunCMake_test(ObjectLibrary)
 add_RunCMake_test(TargetObjects)
 add_RunCMake_test(TargetSources)
 add_RunCMake_test(find_dependency)
+add_RunCMake_test(CompileFeatures)
 if(NOT WIN32)
   add_RunCMake_test(PositionIndependentCode)
   set(SKIP_VISIBILITY 0)
diff --git a/Tests/RunCMake/CompileFeatures/CMakeLists.txt b/Tests/RunCMake/CompileFeatures/CMakeLists.txt
new file mode 100644
index 0000000..3482e6b
--- /dev/null
+++ b/Tests/RunCMake/CompileFeatures/CMakeLists.txt
@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 3.0)
+project(${RunCMake_TEST} CXX)
+include(${RunCMake_TEST}.cmake)
diff --git a/Tests/RunCMake/CompileFeatures/NotAFeature-result.txt b/Tests/RunCMake/CompileFeatures/NotAFeature-result.txt
new file mode 100644
index 0000000..d00491f
--- /dev/null
+++ b/Tests/RunCMake/CompileFeatures/NotAFeature-result.txt
@@ -0,0 +1 @@
+1
diff --git a/Tests/RunCMake/CompileFeatures/NotAFeature-stderr.txt b/Tests/RunCMake/CompileFeatures/NotAFeature-stderr.txt
new file mode 100644
index 0000000..ff60e50
--- /dev/null
+++ b/Tests/RunCMake/CompileFeatures/NotAFeature-stderr.txt
@@ -0,0 +1,2 @@
+CMake Error in CMakeLists.txt:
+  Specified unknown feature "not_a_feature" for target "somelib".
diff --git a/Tests/RunCMake/CompileFeatures/NotAFeature.cmake b/Tests/RunCMake/CompileFeatures/NotAFeature.cmake
new file mode 100644
index 0000000..35246c8
--- /dev/null
+++ b/Tests/RunCMake/CompileFeatures/NotAFeature.cmake
@@ -0,0 +1,3 @@
+
+add_library(somelib STATIC empty.cpp)
+set_property(TARGET somelib PROPERTY COMPILE_FEATURES "not_a_feature")
diff --git a/Tests/RunCMake/CompileFeatures/RunCMakeTest.cmake b/Tests/RunCMake/CompileFeatures/RunCMakeTest.cmake
new file mode 100644
index 0000000..3c999e6
--- /dev/null
+++ b/Tests/RunCMake/CompileFeatures/RunCMakeTest.cmake
@@ -0,0 +1,3 @@
+include(RunCMake)
+
+run_cmake(NotAFeature)
diff --git a/Tests/RunCMake/CompileFeatures/empty.cpp b/Tests/RunCMake/CompileFeatures/empty.cpp
new file mode 100644
index 0000000..bfbbdde
--- /dev/null
+++ b/Tests/RunCMake/CompileFeatures/empty.cpp
@@ -0,0 +1,7 @@
+#ifdef _WIN32
+__declspec(dllexport)
+#endif
+int empty()
+{
+  return 0;
+}
diff --git a/Tests/SystemInformation/SystemInformation.in b/Tests/SystemInformation/SystemInformation.in
index 92b24e2..954a2fe 100644
--- a/Tests/SystemInformation/SystemInformation.in
+++ b/Tests/SystemInformation/SystemInformation.in
@@ -25,6 +25,8 @@ CMAKE_CXX98_STANDARD_COMPILE_OPTION == "${CMAKE_CXX98_STANDARD_COMPILE_OPTION}"
 CMAKE_CXX11_STANDARD_COMPILE_OPTION == "${CMAKE_CXX11_STANDARD_COMPILE_OPTION}"
 CMAKE_CXX98_EXTENSION_COMPILE_OPTION == "${CMAKE_CXX98_EXTENSION_COMPILE_OPTION}"
 CMAKE_CXX11_EXTENSION_COMPILE_OPTION == "${CMAKE_CXX11_EXTENSION_COMPILE_OPTION}"
+CMAKE_CXX_COMPILE_FEATURES == "${CMAKE_CXX_COMPILE_FEATURES}"
+CMAKE_CXX11_COMPILE_FEATURES == "${CMAKE_CXX11_COMPILE_FEATURES}"
 
 // C shared library flag
 CMAKE_SHARED_LIBRARY_C_FLAGS == "${CMAKE_SHARED_LIBRARY_C_FLAGS}"