ENH: merge CMake-CrossCompileBasic to HEAD

-add a RESULT_VARIABLE to INCLUDE()
-add CMAKE_TOOLCHAIN_FILE for specifiying your (potentially crosscompiling) toolchain
-have TRY_RUN() complain if you try to use it in crosscompiling mode (which were compiled but cannot run on this system)
-use CMAKE_EXECUTABLE_SUFFIX in TRY_RUN(), probably TRY_RUN won't be able to
run the executables if they have a different suffix because they are
probably crosscompiled, but nevertheless it should be able to find them
-make several cmake variables presettable by the user: CMAKE_C/CXX_COMPILER, CMAKE_C/CXX_OUTPUT_EXTENSION, CMAKE_SYSTEM_NAME, CMAKE_SYSTEM_INFO_FILE
-support prefix for GNU toolchains (arm-elf-gcc, arm-elf-ar, arm-elf-strip etc.)
-move ranlib on OSX from the file command to a command in executed in cmake_install.cmake
-add support for stripping during install in cmake_install.cmake
-split out cl.cmake from Windows-cl.cmake, first (very incomplete) step to support MS crosscompiling tools
-remove stdio.h from the simple C program which checks if the compiler works, since this may not exist for some embedded platforms
-create a new CMakeFindBinUtils.cmake which collects the search fro ar, ranlib, strip, ld, link, install_name_tool and other tools like these
-add support for CMAKE_FIND_ROOT_PATH for all FIND_XXX commands, which is a
list of directories which will be prepended to all search directories, right
now as a cmake variable, turning it into a global cmake property may need
some more work
-remove cmTestTestHandler::TryExecutable(), it's unused
-split cmFileCommand::HandleInstall() into slightly smaller functions

Alex

1 files changed, 8 insertions, 5 deletions

diff --git a/Modules/CMakeSystemSpecificInformation.cmake b/Modules/CMakeSystemSpecificInformation.cmake
index 53905eb..b2c5671 100644
--- a/Modules/CMakeSystemSpecificInformation.cmake
+++ b/Modules/CMakeSystemSpecificInformation.cmake
@@ -7,10 +7,13 @@
 INCLUDE(CMakeGenericSystem)
 
 # 2. now include SystemName.cmake file to set the system specific information
-SET(CMAKE_SYSTEM_INFO_FILE ${CMAKE_ROOT}/Modules/Platform/${CMAKE_SYSTEM_NAME}.cmake)
-IF(EXISTS ${CMAKE_SYSTEM_INFO_FILE})
-  INCLUDE(Platform/${CMAKE_SYSTEM_NAME} OPTIONAL)
-ELSE(EXISTS ${CMAKE_SYSTEM_INFO_FILE})
+IF(NOT CMAKE_SYSTEM_INFO_FILE)
+  SET(CMAKE_SYSTEM_INFO_FILE Platform/${CMAKE_SYSTEM_NAME})
+ENDIF(NOT CMAKE_SYSTEM_INFO_FILE)
+
+INCLUDE(${CMAKE_SYSTEM_INFO_FILE} OPTIONAL RESULT_VARIABLE _INCLUDED_SYSTEM_INFO_FILE)
+
+IF(NOT _INCLUDED_SYSTEM_INFO_FILE)
   MESSAGE("System is unknown to cmake, create:\n${CMAKE_SYSTEM_INFO_FILE}"
           " to use this system, please send your config file to "
           "cmake@www.cmake.org so it can be added to cmake")
@@ -20,7 +23,7 @@ ELSE(EXISTS ${CMAKE_SYSTEM_INFO_FILE})
     MESSAGE("You CMakeCache.txt file was copied to CopyOfCMakeCache.txt. " 
             "Please send that file to cmake@www.cmake.org.")
    ENDIF(EXISTS ${CMAKE_BINARY_DIR}/CMakeCache.txt)
-ENDIF(EXISTS ${CMAKE_SYSTEM_INFO_FILE})
+ENDIF(NOT _INCLUDED_SYSTEM_INFO_FILE)
 
 
 # for most systems a module is the same as a shared library