ENH: set UNIX, WIN32 and APPLE in cmMakefile.cxx as it was before, so it

works for scripts, then reset them in CMakeSystemSpecificInformation.cxx, so
the platform modules can set them again for the target system

Alex

Modules/CMakeDetermineSystem.cmake

@@ -60,19 +60,6 @@ ELSE(CMAKE_HOST_UNIX)
   ENDIF(CMAKE_HOST_WIN32)
 ENDIF(CMAKE_HOST_UNIX)
 
-# this is for compatibility
-# with cmake 2.4 these variables were compiled in
-# now that cmake has to separate between host and target platform
-# two sets are needed. For compatibility the old set of variables is here 
-# set to the compiled-in values, so they still work in custom
-# language or compiler modules where they might be used.
-# After that they are reset in CMakeSystemSpecificInformation.cmake
-# and then set according to the current target platform in the Modules/${CMAKE_SYSTEM_NAME}.cmake file
-SET(APPLE  ${CMAKE_HOST_APPLE})
-SET(UNIX   ${CMAKE_HOST_UNIX})
-SET(CYGWIN ${CMAKE_HOST_CYGWIN})
-SET(WIN32  ${CMAKE_HOST_WIN32})
-
 # if a toolchain file is used, the user wants to cross compile.
 # in this case read the toolchain file and keep the CMAKE_HOST_SYSTEM_*
 # variables around so they can be used in CMakeLists.txt. 

Modules/CMakeSystemSpecificInformation.cmake

@@ -3,11 +3,11 @@
 # It is included after the compiler has been determined, so
 # we know things like the compiler name and if the compiler is gnu.
 
-# before cmake 2.6 these variables were compiled-in in cmake
-# now they are set in the Modules/${CMAKE_SYSTEM_NAME}.cmake file
-# In order to keep custom language or compiler files working which might use
-# these variables, they are set to the value of the compiled-in variables in
-# CMakeDetermineSystem.cmake and reset here.
+# before cmake 2.6 these variables were set in cmMakefile.cxx. This is still
+# done to keep scripts and custom language and compiler modules working.
+# But they are reset here and set again in the platform files for the target
+# platform, so they can be used for testing the target platform instead
+# of testing the host platform.
 SET(APPLE  )
 SET(UNIX   )
 SET(CYGWIN )

Source/cmMakefile.cxx

@@ -1911,16 +1911,31 @@ void cmMakefile::RemoveVariablesInString(std::string& source,
  */
 void cmMakefile::AddDefaultDefinitions()
 {
+/* Up to CMake 2.4 here only WIN32, UNIX and APPLE were set.
+  With CMake must separate between target and host platform. In most cases
+  the tests for WIN32, UNIX and APPLE will be for the target system, so an 
+  additional set of variables for the host system is required ->
+  CMAKE_HOST_WIN32, CMAKE_HOST_UNIX, CMAKE_HOST_APPLE.
+  WIN32, UNIX and APPLE are now set in the platform files in 
+  Modules/Platforms/.
+  To keep cmake scripts (-P) and custom language and compiler modules
+  working, these variables are still also set here in this place, but they
+  will be reset in CMakeSystemSpecificInformation.cmake before the platform 
+  files are executed. */
 #if defined(_WIN32) || defined(__CYGWIN__)
+  this->AddDefinition("WIN32", "1");
   this->AddDefinition("CMAKE_HOST_WIN32", "1");
 #else
+  this->AddDefinition("UNIX", "1");
   this->AddDefinition("CMAKE_HOST_UNIX", "1");
 #endif
   // Cygwin is more like unix so enable the unix commands
 #if defined(__CYGWIN__)
+  this->AddDefinition("UNIX", "1");
   this->AddDefinition("CMAKE_HOST_UNIX", "1");
 #endif
 #if defined(__APPLE__)
+  this->AddDefinition("APPLE", "1");
   this->AddDefinition("CMAKE_HOST_APPLE", "1");
 #endif