[Eva] Handle logic coercion from singleton to set

src/plugins/eva/legacy/eval_terms.ml

@@ -1162,10 +1162,13 @@ let rec eval_term ~alarm_mode env t =
          ldeps = r.ldeps;
          eover; eunder = under_from_over eover;
          empty = r.empty }
-     | _ ->
+     | ltyp ->
        if Logic_const.is_boolean_type ltyp
        && Logic_typing.is_integral_type t.term_type
        then cast_to_bool r
+       else if Logic_utils.is_same_type ltyp t.term_type then
+         (* coercion from singleton to set *)
+         r
        else
          unsupported
            (Format.asprintf "logic coercion %a -> %a@."

tests/libc/oracle/signal_h.res.oracle

@@ -129,8 +129,6 @@
   function sigaction: precondition 'valid_read_act_or_null' got status valid.
 [eva] signal_h.c:48: 
   function sigaction: precondition 'separation,separated_acts' got status valid.
-[eva] FRAMAC_SHARE/libc/signal.h:248: 
-  cannot evaluate ACSL term, unsupported ACSL construct: logic coercion struct sigaction -> set<struct sigaction>
 [eva:garbled-mix:assigns] signal_h.c:48: 
   The specification of function sigaction
   has generated a garbled mix of addresses for assigns clause *oldact.