+ This guard prevents errors by the C compiler when the Nit code imports this
+ module but do not use handle_signal. When it is _not_ used, the C type
+ SignalHandler and C function SignalHandler_receive_signal are not generated.
+ Which does not please the C compiler. This guard ensure that we compile this
+ code only if the type SignalHandler has been defined.
+
+ This is a HACK, FIXME by:
+ * Adding the macro to the FFI spec, or
+ * Attach the callbacks to this code block (or the module itself)
+ * Avoid using Nit types and callbacks or use them only in the C implementation
+ of Nit method.
+ */
+ #ifdef NIT_TYPE_SignalHandler
+
+ /*