Check default GCC architecture: 32 or 64 bit

Author: Boris Brodski

CMakeLists.txt

@@ -17,6 +17,7 @@ IF (NOT CMAKE_BUILD_TYPE)
 ENDIF()
 
 INCLUDE(cmake/FindJavaExtended.cmake)
+INCLUDE(cmake/CheckGCC.cmake)
 INCLUDE(CTest)
 
 

cmake/CheckGCC.cmake

@@ -0,0 +1,32 @@
+IF(NOT GCC_ARCH)
+    MESSAGE("-- Checking gcc architecture")
+    SET(GCC_TEST_DIR "${PROJECT_BINARY_DIR}/gcc-test")
+    FILE(MAKE_DIRECTORY "${GCC_TEST_DIR}")
+    FILE(WRITE "${GCC_TEST_DIR}/test64.c" "int a[sizeof(void*)-7];\n")
+    FILE(WRITE "${GCC_TEST_DIR}/test32.c" "int a[sizeof(void*)-3];\n")
+    EXECUTE_PROCESS(COMMAND ${CMAKE_C_COMPILER} -c test64.c 
+                    WORKING_DIRECTORY ${GCC_TEST_DIR}
+                    RESULT_VARIABLE gcc_test64_result
+                    OUTPUT_VARIABLE gcc_test64_output 
+                    ERROR_VARIABLE gcc_test64_err)
+    EXECUTE_PROCESS(COMMAND ${CMAKE_C_COMPILER} -c test32.c
+                    WORKING_DIRECTORY ${GCC_TEST_DIR}
+                    RESULT_VARIABLE gcc_test32_result
+                    OUTPUT_VARIABLE gcc_test32_output 
+                    ERROR_VARIABLE gcc_test32_err)
+    MESSAGE("${gcc_test64_result}")
+    MESSAGE("${gcc_test32_result}")
+    IF(gcc_test64_result)
+        IF(gcc_test32_result)
+            MESSAGE(FATAL_ERROR "${CMAKE_C_COMPILER} can't compile simple c-programs.
+Test64 output: ${gcc_test64_err}
+Test32 output: ${gcc_test32_err}")
+        ELSE()
+            SET(GCC_ARCH "32" CACHE INTERNAL "Javac test passed")
+        ENDIF()
+    ELSE()
+        SET(GCC_ARCH "64" CACHE INTERNAL "Javac test passed")
+    ENDIF()
+    MESSAGE("-- Checking gcc architecture - ${GCC_ARCH} bit")
+ENDIF()
+