Use the file-utility to test for 64bit if there is no /usr/lib64

Alex

Modules/CMakeFindPackageMode.cmake

@@ -45,10 +45,18 @@ if(UNIX)
   # try to guess whether we have a 64bit system, if it has not been set
   # from the outside
   if(NOT CMAKE_SIZEOF_VOID_P)
+    set(CMAKE_SIZEOF_VOID_P 4)
     if(EXISTS /usr/lib64)
       set(CMAKE_SIZEOF_VOID_P 8)
     else()
-      set(CMAKE_SIZEOF_VOID_P 4)
+      # use the file utility to check whether itself is 64 bit:
+      find_program(FILE_EXECUTABLE file)
+      if(FILE_EXECUTABLE)
+        execute_process(COMMAND "${FILE_EXECUTABLE}" "${FILE_EXECUTABLE}" OUTPUT_VARIABLE fileOutput ERROR_QUIET)
+        if("${fileOutput}" MATCHES "64-bit")
+          set(CMAKE_SIZEOF_VOID_P 8)
+        endif()
+      endif()
     endif()
   endif()
 
@@ -56,7 +64,6 @@ if(UNIX)
   if(EXISTS /etc/debian_version)
     if(NOT CMAKE_${LANGUAGE}_LANGUAGE_ARCHITECTURE )
       file(GLOB filesInLib RELATIVE /lib /lib/*-linux-gnu* )
-      list(APPEND filesInLib i386-linux-gnu)
       foreach(file ${filesInLib})
         if("${file}" MATCHES "${CMAKE_LIBRARY_ARCHITECTURE_REGEX}")
           set(CMAKE_${LANGUAGE}_LANGUAGE_ARCHITECTURE ${file})