ENH: check for CMAKE_HOST_SYSTEM_NAME to decide whether to load

CMakeDetermineSystem.cmake, since CMAKE_SYSTEM_NAME might already be preset
when using cmake for cross compiling
use type STRING instead of FILEPATH since otherwise a strange filename was
generated

Alex

Modules/CMakeDetermineCCompiler.cmake

@@ -75,7 +75,7 @@ ELSE(NOT CMAKE_C_COMPILER)
     FIND_PROGRAM(CMAKE_C_COMPILER_WITH_PATH NAMES ${CMAKE_C_COMPILER})
     MARK_AS_ADVANCED(CMAKE_C_COMPILER_WITH_PATH)
     IF(CMAKE_C_COMPILER_WITH_PATH)
-      SET(CMAKE_C_COMPILER ${CMAKE_C_COMPILER_WITH_PATH} CACHE FILEPATH "C compiler" FORCE)
+      SET(CMAKE_C_COMPILER ${CMAKE_C_COMPILER_WITH_PATH} CACHE STRING "C compiler" FORCE)
     ENDIF(CMAKE_C_COMPILER_WITH_PATH)
   ENDIF(NOT _CMAKE_USER_C_COMPILER_PATH)
 ENDIF(NOT CMAKE_C_COMPILER)

Modules/CMakeDetermineCXXCompiler.cmake

@@ -73,7 +73,7 @@ ELSE(NOT CMAKE_CXX_COMPILER)
     FIND_PROGRAM(CMAKE_CXX_COMPILER_WITH_PATH NAMES ${CMAKE_CXX_COMPILER})
     MARK_AS_ADVANCED(CMAKE_CXX_COMPILER_WITH_PATH)
     IF(CMAKE_CXX_COMPILER_WITH_PATH)
-      SET(CMAKE_CXX_COMPILER ${CMAKE_CXX_COMPILER_WITH_PATH} CACHE FILEPATH "CXX compiler" FORCE)
+      SET(CMAKE_CXX_COMPILER ${CMAKE_CXX_COMPILER_WITH_PATH} CACHE STRING "CXX compiler" FORCE)
     ENDIF(CMAKE_CXX_COMPILER_WITH_PATH)
   ENDIF(NOT _CMAKE_USER_CXX_COMPILER_PATH)
 ENDIF(NOT CMAKE_CXX_COMPILER)

Source/cmGlobalGenerator.cxx

@@ -160,7 +160,7 @@ void cmGlobalGenerator::FindMakeProgram(cmMakefile* mf)
 //
 // CMakeSystem.cmake - configured file created by CMakeDetermineSystem.cmake
 //   CMakeDetermineSystem.cmake - figure out os info and create
-//                                CMakeSystem.cmake IFF CMAKE_SYSTEM_NAME
+//                                CMakeSystem.cmake IF CMAKE_HOST_SYSTEM_NAME
 //                                not set
 //   CMakeSystem.cmake - configured file created by
 //                       CMakeDetermineSystem.cmake IFF CMAKE_SYSTEM_LOADED
@@ -243,7 +243,7 @@ cmGlobalGenerator::EnableLanguage(std::vector<std::string>const& languages,
     }
   //  Load the CMakeDetermineSystem.cmake file and find out
   // what platform we are running on
-  if (!mf->GetDefinition("CMAKE_SYSTEM_NAME"))
+  if (!mf->GetDefinition("CMAKE_HOST_SYSTEM_NAME"))
     {
 #if defined(_WIN32) && !defined(__CYGWIN__)
     /* Windows version number data.  */