Make C++ feature checks extensible

Turn the feature check for cxx11_unordered_map into a function such that we can use it for other features as well. Drop the 11 suffix, as we may want to check features from other standards.
2016-06-23 00:16:15 +02:00 · 2016-06-23 00:16:15 +02:00 · ea5477e43d
parent 68bb74d9e6
commit ea5477e43d
10 changed files with 50 additions and 39 deletions
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@ -67,7 +67,7 @@ if(NOT DEFINED CMAKE_CXX_STANDARD AND NOT CMake_NO_CXX_STANDARD)
  endif()
 endif()
 if(NOT CMake_TEST_EXTERNAL_CMAKE)
-  include(${CMake_SOURCE_DIR}/Source/Checks/cm_cxx11_unordered_map.cmake)
+  include(${CMake_SOURCE_DIR}/Source/Checks/cm_cxx_features.cmake)
 endif()

 # option to set the internal encoding of CMake to UTF-8
--- a/Source/Checks/cm_cxx11_unordered_map.cmake
+++ b/Source/Checks/cm_cxx11_unordered_map.cmake
@ -1,25 +0,0 @@
-
-if(CMAKE_CXX_STANDARD AND NOT DEFINED CMake_HAVE_CXX11_UNORDERED_MAP)
-  message(STATUS "Checking if compiler supports C++11 unordered_map")
-  try_compile(CMake_HAVE_CXX11_UNORDERED_MAP
-    ${CMAKE_CURRENT_BINARY_DIR}
-    ${CMAKE_CURRENT_LIST_DIR}/cm_cxx11_unordered_map.cpp
-    CMAKE_FLAGS -DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}
-    OUTPUT_VARIABLE OUTPUT
-    )
-  if(CMake_HAVE_CXX11_UNORDERED_MAP)
-    message(STATUS "Checking if compiler supports C++11 unordered_map - yes")
-    file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
-      "Determining if compiler supports C++11 unordered_map passed with the following output:\n"
-      "${OUTPUT}\n"
-      "\n"
-      )
-  else()
-    message(STATUS "Checking if compiler supports C++11 unordered_map - no")
-    file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
-      "Determining if compiler supports C++11 unordered_map failed with the following output:\n"
-      "${OUTPUT}\n"
-      "\n"
-      )
-  endif()
-endif()
--- a/Source/Checks/cm_cxx_features.cmake
+++ b/Source/Checks/cm_cxx_features.cmake
@ -0,0 +1,36 @@
+
+function(cm_check_cxx_feature name)
+  string(TOUPPER ${name} FEATURE)
+  if(NOT DEFINED CMake_HAVE_CXX_${FEATURE})
+    message(STATUS "Checking if compiler supports C++ ${name}")
+    try_compile(CMake_HAVE_CXX_${FEATURE}
+      ${CMAKE_CURRENT_BINARY_DIR}
+      ${CMAKE_CURRENT_LIST_DIR}/cm_cxx_${name}.cxx
+      CMAKE_FLAGS -DCMAKE_CXX_STANDARD=${CMAKE_CXX_STANDARD}
+      OUTPUT_VARIABLE OUTPUT
+      )
+    # If using the feature causes warnings, treat it as broken/unavailable.
+    if(OUTPUT MATCHES "warning")
+      set(CMake_HAVE_CXX_${FEATURE} OFF CACHE INTERNAL "TRY_COMPILE" FORCE)
+    endif()
+    if(CMake_HAVE_CXX_${FEATURE})
+      message(STATUS "Checking if compiler supports C++ ${name} - yes")
+      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeOutput.log
+        "Determining if compiler supports C++ ${name} passed with the following output:\n"
+        "${OUTPUT}\n"
+        "\n"
+        )
+    else()
+      message(STATUS "Checking if compiler supports C++ ${name} - no")
+      file(APPEND ${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeError.log
+        "Determining if compiler supports C++ ${name} failed with the following output:\n"
+        "${OUTPUT}\n"
+        "\n"
+        )
+    endif()
+  endif()
+endfunction()
+
+if(CMAKE_CXX_STANDARD)
+  cm_check_cxx_feature(unordered_map)
+endif()
--- a/Source/Checks/cm_cxx11_unordered_map.cpp
+++ b/Source/Checks/cm_cxx11_unordered_map.cpp
--- a/Source/cmConfigure.cmake.h.in
+++ b/Source/cmConfigure.cmake.h.in
@ -29,7 +29,7 @@
 #cmakedefine CMAKE_USE_ELF_PARSER
 #cmakedefine CMAKE_USE_MACH_PARSER
 #cmakedefine CMAKE_ENCODING_UTF8
-#cmakedefine CMake_HAVE_CXX11_UNORDERED_MAP
+#cmakedefine CMake_HAVE_CXX_UNORDERED_MAP
 #define CMAKE_BIN_DIR "/@CMAKE_BIN_DIR@"
 #define CMAKE_DATA_DIR "/@CMAKE_DATA_DIR@"

--- a/Source/cmDefinitions.h
+++ b/Source/cmDefinitions.h
@ -17,7 +17,7 @@
 #include "cmLinkedTree.h"

 #if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#ifdef CMake_HAVE_CXX_UNORDERED_MAP
 #include <unordered_map>
 #else
 #include "cmsys/hash_map.hxx"
@ -92,7 +92,7 @@ private:
  static Def NoDef;

 #if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#ifdef CMake_HAVE_CXX_UNORDERED_MAP
  typedef std::unordered_map<std::string, Def> MapType;
 #else
  typedef cmsys::hash_map<std::string, Def> MapType;
--- a/Source/cmFileTimeComparison.cxx
+++ b/Source/cmFileTimeComparison.cxx
@ -13,7 +13,7 @@

 // Use a hash table to avoid duplicate file time checks from disk.
 #if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#ifdef CMake_HAVE_CXX_UNORDERED_MAP
 #include <unordered_map>
 #else
 #include <cmsys/hash_map.hxx>
@ -47,13 +47,13 @@ private:
  {
  public:
    size_t operator()(const std::string& s) const { return h(s.c_str()); }
-#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#ifdef CMake_HAVE_CXX_UNORDERED_MAP
    std::hash<const char*> h;
 #else
    cmsys::hash<const char*> h;
 #endif
  };
-#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#ifdef CMake_HAVE_CXX_UNORDERED_MAP
  typedef std::unordered_map<std::string,
 #else
  typedef cmsys::hash_map<std::string,
--- a/Source/cmGlobalGenerator.h
+++ b/Source/cmGlobalGenerator.h
@ -25,7 +25,7 @@

 #if defined(CMAKE_BUILD_WITH_CMAKE)
 #include "cmFileLockPool.h"
-#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#ifdef CMake_HAVE_CXX_UNORDERED_MAP
 #include <unordered_map>
 #else
 #include <cmsys/hash_map.hxx>
@ -433,7 +433,7 @@ protected:

 private:
 #if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#ifdef CMake_HAVE_CXX_UNORDERED_MAP
  typedef std::unordered_map<std::string, cmTarget*> TargetMap;
  typedef std::unordered_map<std::string, cmGeneratorTarget*>
    GeneratorTargetMap;
--- a/Source/cmMakefile.h
+++ b/Source/cmMakefile.h
@ -31,7 +31,7 @@
 #include <cmsys/RegularExpression.hxx>
 #include <cmsys/auto_ptr.hxx>
 #if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#ifdef CMake_HAVE_CXX_UNORDERED_MAP
 #include <unordered_map>
 #else
 #include <cmsys/hash_map.hxx>
@ -796,7 +796,7 @@ protected:
  // libraries, classes, and executables
  mutable cmTargets Targets;
 #if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#ifdef CMake_HAVE_CXX_UNORDERED_MAP
  typedef std::unordered_map<std::string, cmTarget*> TargetMap;
 #else
  typedef cmsys::hash_map<std::string, cmTarget*> TargetMap;
@ -915,7 +915,7 @@ private:

 // A map for fast output to input look up.
 #if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#ifdef CMake_HAVE_CXX_UNORDERED_MAP
  typedef std::unordered_map<std::string, cmSourceFile*> OutputToSourceMap;
 #else
  typedef cmsys::hash_map<std::string, cmSourceFile*> OutputToSourceMap;
--- a/Source/cmTarget.h
+++ b/Source/cmTarget.h
@ -21,7 +21,7 @@

 #include <cmsys/auto_ptr.hxx>
 #if defined(CMAKE_BUILD_WITH_CMAKE)
-#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#ifdef CMake_HAVE_CXX_UNORDERED_MAP
 #include <unordered_map>
 #else
 #include <cmsys/hash_map.hxx>
@ -331,7 +331,7 @@ private:
 };

 #ifdef CMAKE_BUILD_WITH_CMAKE
-#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#ifdef CMake_HAVE_CXX_UNORDERED_MAP
 typedef std::unordered_map<std::string, cmTarget> cmTargets;
 #else
 typedef cmsys::hash_map<std::string, cmTarget> cmTargets;