Load platform files that need to know the ABI when possible

Load platform files named in CMAKE_<lang>_ABI_FILES for each language
once the ABI sizeof(void*) is known.  During the first configuration
this is after the test for working compiler and ABI detection checks.
During later configurations the ABI information is immediately available
because it has been saved in CMake<lang>Compiler.cmake.

Modules/CMakeCInformation.cmake

@@ -68,6 +68,12 @@ IF (NOT _INCLUDED_FILE)
   INCLUDE(Platform/${CMAKE_SYSTEM_NAME} OPTIONAL)
 ENDIF (NOT _INCLUDED_FILE)
 
+IF(CMAKE_C_SIZEOF_DATA_PTR)
+  FOREACH(f ${CMAKE_C_ABI_FILES})
+    INCLUDE(${f})
+  ENDFOREACH()
+  UNSET(CMAKE_C_ABI_FILES)
+ENDIF()
 
 # This should be included before the _INIT variables are
 # used to initialize the cache.  Since the rule variables 

Modules/CMakeCXXInformation.cmake

@@ -67,6 +67,12 @@ IF (NOT _INCLUDED_FILE)
   INCLUDE(Platform/${CMAKE_SYSTEM_NAME} OPTIONAL)
 ENDIF (NOT _INCLUDED_FILE)
 
+IF(CMAKE_CXX_SIZEOF_DATA_PTR)
+  FOREACH(f ${CMAKE_CXX_ABI_FILES})
+    INCLUDE(${f})
+  ENDFOREACH()
+  UNSET(CMAKE_CXX_ABI_FILES)
+ENDIF()
 
 # This should be included before the _INIT variables are
 # used to initialize the cache.  Since the rule variables 

Modules/CMakeFortranInformation.cmake

@@ -44,6 +44,12 @@ IF (NOT _INCLUDED_FILE)
   INCLUDE(Platform/${CMAKE_SYSTEM_NAME} OPTIONAL)
 ENDIF (NOT _INCLUDED_FILE)
 
+IF(CMAKE_Fortran_SIZEOF_DATA_PTR)
+  FOREACH(f ${CMAKE_Fortran_ABI_FILES})
+    INCLUDE(${f})
+  ENDFOREACH()
+  UNSET(CMAKE_Fortran_ABI_FILES)
+ENDIF()
 
 # This should be included before the _INIT variables are
 # used to initialize the cache.  Since the rule variables 

Modules/CMakeTestCCompiler.cmake

@@ -76,5 +76,11 @@ ELSE(NOT CMAKE_C_COMPILER_WORKS)
       )
     INCLUDE(${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeCCompiler.cmake)
   ENDIF(CMAKE_C_COMPILER_FORCED)
+  IF(CMAKE_C_SIZEOF_DATA_PTR)
+    FOREACH(f ${CMAKE_C_ABI_FILES})
+      INCLUDE(${f})
+    ENDFOREACH()
+    UNSET(CMAKE_C_ABI_FILES)
+  ENDIF()
 ENDIF(NOT CMAKE_C_COMPILER_WORKS)
 

Modules/CMakeTestCXXCompiler.cmake

@@ -69,4 +69,10 @@ ELSE(NOT CMAKE_CXX_COMPILER_WORKS)
       )
     INCLUDE(${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeCXXCompiler.cmake)
   ENDIF(CMAKE_CXX_COMPILER_FORCED)
+  IF(CMAKE_CXX_SIZEOF_DATA_PTR)
+    FOREACH(f ${CMAKE_CXX_ABI_FILES})
+      INCLUDE(${f})
+    ENDFOREACH()
+    UNSET(CMAKE_CXX_ABI_FILES)
+  ENDIF()
 ENDIF(NOT CMAKE_CXX_COMPILER_WORKS)

Modules/CMakeTestFortranCompiler.cmake

@@ -92,4 +92,10 @@ ELSE(NOT CMAKE_Fortran_COMPILER_WORKS)
       )
     INCLUDE(${CMAKE_BINARY_DIR}${CMAKE_FILES_DIRECTORY}/CMakeFortranCompiler.cmake)
   ENDIF(CMAKE_Fortran_COMPILER_FORCED)
+  IF(CMAKE_Fortran_SIZEOF_DATA_PTR)
+    FOREACH(f ${CMAKE_Fortran_ABI_FILES})
+      INCLUDE(${f})
+    ENDFOREACH()
+    UNSET(CMAKE_Fortran_ABI_FILES)
+  ENDIF()
 ENDIF(NOT CMAKE_Fortran_COMPILER_WORKS)

Source/cmDocumentVariables.cxx

@@ -1515,6 +1515,8 @@ void cmDocumentVariables::DefineVariables(cmake* cm)
                      cmProperty::VARIABLE,0,0);
   cm->DefineProperty("CMAKE_<LANG>_COMPILER_ID_RUN",
                      cmProperty::VARIABLE,0,0);
+  cm->DefineProperty("CMAKE_<LANG>_ABI_FILES",
+                     cmProperty::VARIABLE,0,0);
   cm->DefineProperty("CMAKE_<LANG>_CREATE_ASSEMBLY_SOURCE",
                      cmProperty::VARIABLE,0,0);
   cm->DefineProperty("CMAKE_<LANG>_CREATE_PREPROCESSED_SOURCE",