Use std::unordered_map instead of hash_map where available.

CMakeLists.txt

@@ -48,6 +48,7 @@ if(NOT DEFINED CMAKE_CXX_STANDARD AND NOT CMake_NO_CXX_STANDARD)
     set(CMAKE_CXX_STANDARD 11)
   endif()
 endif()
+include(${CMake_SOURCE_DIR}/Source/Checks/cm_cxx11_unordered_map.cmake)
 
 # option to set the internal encoding of CMake to UTF-8
 option(CMAKE_ENCODING_UTF8 "Use UTF-8 encoding internally." ON)

Source/Checks/cm_cxx11_unordered_map.cmake

@@ -0,0 +1,25 @@
+
+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()

Source/Checks/cm_cxx11_unordered_map.cpp

@@ -0,0 +1,6 @@
+#include <unordered_map>
+int main() {
+  std::unordered_map<int, int> map;
+  map[0] = 0;
+  return 0;
+}

Source/cmConfigure.cmake.h.in

@@ -14,4 +14,5 @@
 #cmakedefine CMAKE_USE_ELF_PARSER
 #cmakedefine CMAKE_USE_MACH_PARSER
 #cmakedefine CMAKE_ENCODING_UTF8
+#cmakedefine CMake_HAVE_CXX11_UNORDERED_MAP
 #define CMAKE_DATA_DIR "/@CMAKE_DATA_DIR@"

Source/cmDefinitions.h

@@ -14,8 +14,12 @@
 
 #include "cmStandardIncludes.h"
 #if defined(CMAKE_BUILD_WITH_CMAKE)
+#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#include <unordered_map>
+#else
 #include "cmsys/hash_map.hxx"
 #endif
+#endif
 
 #include <list>
 
@@ -65,9 +69,12 @@ private:
   };
   static Def NoDef;
 
-  // Local definitions, set or unset.
 #if defined(CMAKE_BUILD_WITH_CMAKE)
+#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+  typedef std::unordered_map<std::string, Def> MapType;
+#else
   typedef cmsys::hash_map<std::string, Def> MapType;
+#endif
 #else
   typedef std::map<std::string, Def> MapType;
 #endif

Source/cmFileTimeComparison.cxx

@@ -13,8 +13,12 @@
 
 // Use a hash table to avoid duplicate file time checks from disk.
 #if defined(CMAKE_BUILD_WITH_CMAKE)
+#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#include <unordered_map>
+#else
 # include <cmsys/hash_map.hxx>
 #endif
+#endif
 
 #include <cmsys/Encoding.hxx>
 
@@ -47,9 +51,17 @@ private:
       {
       return h(s.c_str());
       }
+#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+    std::hash<const char*> h;
+#else
     cmsys::hash<const char*> h;
+#endif
     };
+#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+  typedef std::unordered_map<std::string,
+#else
   typedef cmsys::hash_map<std::string,
+#endif
                           cmFileTimeComparison_Type, HashString> FileStatsMap;
   FileStatsMap Files;
 #endif

Source/cmGlobalGenerator.h

@@ -24,7 +24,11 @@
 
 #if defined(CMAKE_BUILD_WITH_CMAKE)
 # include "cmFileLockPool.h"
-# include <cmsys/hash_map.hxx>
+# ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#  include <unordered_map>
+# else
+#  include <cmsys/hash_map.hxx>
+# endif
 #endif
 
 class cmake;
@@ -429,7 +433,11 @@ protected:
 
   // All targets in the entire project.
 #if defined(CMAKE_BUILD_WITH_CMAKE)
+#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+  typedef std::unordered_map<std::string, cmTarget*> TargetMap;
+#else
   typedef cmsys::hash_map<std::string, cmTarget*> TargetMap;
+#endif
 #else
   typedef std::map<std::string,cmTarget *> TargetMap;
 #endif

Source/cmMakefile.h

@@ -31,7 +31,11 @@
 #include <cmsys/auto_ptr.hxx>
 #include <cmsys/RegularExpression.hxx>
 #if defined(CMAKE_BUILD_WITH_CMAKE)
-# include <cmsys/hash_map.hxx>
+# ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#  include <unordered_map>
+# else
+#  include <cmsys/hash_map.hxx>
+# endif
 #endif
 
 #include <stack>
@@ -868,7 +872,11 @@ protected:
   // libraries, classes, and executables
   mutable cmTargets Targets;
 #if defined(CMAKE_BUILD_WITH_CMAKE)
+#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+  typedef std::unordered_map<std::string, cmTarget*> TargetMap;
+#else
   typedef cmsys::hash_map<std::string, cmTarget*> TargetMap;
+#endif
 #else
   typedef std::map<std::string, cmTarget*> TargetMap;
 #endif
@@ -1041,7 +1049,11 @@ private:
 
   // A map for fast output to input look up.
 #if defined(CMAKE_BUILD_WITH_CMAKE)
+#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+  typedef std::unordered_map<std::string, cmSourceFile*> OutputToSourceMap;
+#else
   typedef cmsys::hash_map<std::string, cmSourceFile*> OutputToSourceMap;
+#endif
 #else
   typedef std::map<std::string, cmSourceFile*> OutputToSourceMap;
 #endif

Source/cmTarget.h

@@ -19,7 +19,11 @@
 
 #include <cmsys/auto_ptr.hxx>
 #if defined(CMAKE_BUILD_WITH_CMAKE)
-#include <cmsys/hash_map.hxx>
+# ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+#  include <unordered_map>
+# else
+#  include <cmsys/hash_map.hxx>
+# endif
 #endif
 
 #define CM_FOR_EACH_TARGET_POLICY(F) \
@@ -849,7 +853,11 @@ private:
 };
 
 #ifdef CMAKE_BUILD_WITH_CMAKE
-typedef cmsys::hash_map<std::string,cmTarget> cmTargets;
+#ifdef CMake_HAVE_CXX11_UNORDERED_MAP
+typedef std::unordered_map<std::string, cmTarget> cmTargets;
+#else
+typedef cmsys::hash_map<std::string, cmTarget> cmTargets;
+#endif
 #else
 typedef std::map<std::string,cmTarget> cmTargets;
 #endif