ITK/Cross Compiling

This page describes the procedure to follow when cross compiling for another system.

In this page, we will refer to the system as:

• Target System: The system where the executables are intended to run.
• Build System: The system where the executables are built.

In Linux for Mac

In this particular case we illustrate

• Target System = Mac
• Build System = Linux

Major steps

1. Build your tool chain in the build system
   • This is the set of compiler and linker that must be build in the build system, but will know how to generate code for the Target system.
2. Create a TryRun ... file in the native system
   • This could be generated (as a skeleton) with the following commands

Building the ToolChain

The following is a script developed by Johannes Schindelin (originally intended for FIJI)

File:Build-macosx-cross-compiler.sh.gz

Following the advice of the CMake Wiki [1]

Put the following in a file called ToolChain.cmake

 # this one is important
 SET(CMAKE_SYSTEM_NAME Linux)
 #this one not so much
 SET(CMAKE_SYSTEM_VERSION 1)
 # specify the cross compiler
 SET(CMAKE_C_COMPILER   /usr/bin/gcc)
 SET(CMAKE_CXX_COMPILER /usr/bin/g++)
 # where is the target environment
 SET(CMAKE_FIND_ROOT_PATH  /usr)
 # search for programs in the build host directories
 SET(CMAKE_FIND_ROOT_PATH_MODE_PROGRAM NEVER)
 # for libraries and headers in the target directories
 SET(CMAKE_FIND_ROOT_PATH_MODE_LIBRARY ONLY)
 SET(CMAKE_FIND_ROOT_PATH_MODE_INCLUDE ONLY)

and run it with CMake using the command (in an empty directory)

 cmake -DCMAKE_TOOLCHAIN_FILE=./ToolChain.cmake   ~/src/ITK

This will generate (among many other things) a File called

              TryRunResults.cmake

Then, manually populate, the values of each one of the fields.

1. Copy the file to the build system
   • Do the command in the build system.

   cmake -C ~/TryRunResults.cmake  .