Mark unused vars with `(void)x;` [should silence Coverity Scan]

Cython/Compiler/Nodes.py

@@ -6819,7 +6819,8 @@ class TryExceptStatNode(StatNode):
         else:
             # try block cannot raise exceptions, but we had to allocate the temps above,
             # so just keep the C compiler from complaining about them being unused
-            save_exc.putln("if (%s); else {/*mark used*/}" % '||'.join(exc_save_vars))
+            mark_vars_used =  ["(void)%s;" % var for var in exc_save_vars]
+            save_exc.putln("%s /* mark used */" % ' '.join(mark_vars_used))
 
             def restore_saved_exception():
                 pass