Cross compilation fixes

linux-aarch64-toolchain.cmake

@@ -0,0 +1,8 @@
+cmake_minimum_required(VERSION 3.10)
+
+set(CMAKE_C_COMPILER aarch64-linux-gnu-gcc)
+set(CMAKE_CXX_COMPILER aarch64-linux-gnu-g++)
+set(CMAKE_FIND_ROOT_PATH /usr/aarch64-linux-gnu)
+set(CMAKE_PROGRAM_PATH /usr/aarch64-linux-gnu/bin)
+
+set(ENV{AARCH64_CROSS} "1")

readme.md

@@ -131,14 +131,17 @@ The gradle build files for the SOEM wrapper and native libraries are created by
 
 To build and publish run the following commands. Note that the gradle commands are ran from within the build directory.
 
-
-- cd ihmc-ethercat-master
-- mkdir build
-- cd build
-- cmake -DCMAKE_BUILD_TYPE=Release ..
-- make
-- ../gradlew publishToMavenLocal -Ptarget=JAVA
-- ../gradlew publishToMavenLocal -Ptarget=PLATFORM
+```
+cd ihmc-ethercat-master
+mkdir build
+cd build
+cmake -DCMAKE_BUILD_TYPE=Release ..
+# Cross compile for arm64 using the toolchain
+# cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_TOOLCHAIN_FILE=../linux-aarch64-toolchain.cmake ..
+make
+../gradlew publishToMavenLocal -Ptarget=JAVA
+../gradlew publishToMavenLocal -Ptarget=PLATFORM
+```
 
 Note that if you want to publish multiple platform libraries you only have to run target=JAVA on a single platform
 

swig/CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 2.8.4)
+cmake_minimum_required(VERSION 3.10)
 
 set(CMAKE_POSITION_INDEPENDENT_CODE true)
 

swig/settings.gradle.kts.in

@@ -39,7 +39,7 @@ else
    }
    else
    {
-      if (OperatingSystem.current().isLinux() && System.getProperty("os.arch") == "aarch64")
+      if (OperatingSystem.current().isLinux() && (System.getProperty("os.arch") == "aarch64" || System.getenv("AARCH64_CROSS") != null))
       {
          rootProject.name="soem-platform-linux-arm64"
       }

swig/us/ihmc/soem/generated/CMakeLists.txt

@@ -1,4 +1,4 @@
-cmake_minimum_required(VERSION 2.8)
+cmake_minimum_required(VERSION 3.10)
 
 find_package(JNI REQUIRED)
 include_directories(${JNI_INCLUDE_DIRS}) 
@@ -11,9 +11,11 @@ include_directories("/usr/include/soem")
 set_property(SOURCE soem.i PROPERTY SWIG_FLAGS "-package" "us.ihmc.soem.generated")
 
 if(UNIX AND NOT APPLE)
-    if(CMAKE_SYSTEM_PROCESSOR MATCHES "x86_64")
+    if(CMAKE_SYSTEM_PROCESSOR MATCHES "x86_64" AND NOT DEFINED ENV{AARCH64_CROSS})
+        message(STATUS "Using target platform x86_64")
         set(LIBRARY_NAME "soemJava-x86_64")
-    elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64")
+    elseif(CMAKE_SYSTEM_PROCESSOR MATCHES "aarch64" OR DEFINED ENV{AARCH64_CROSS})
+        message(STATUS "Using target platform arm64")
         set(LIBRARY_NAME "soemJava-arm64")
     else()
         message(FATAL_ERROR "Unsupported architecture: ${CMAKE_SYSTEM_PROCESSOR}")