[filecheck] don't delay adding defined locals to set of known vars

they can appear before their `Local_init`, e.g. in a `SizeOfE` in the
size expression of a local array. Furthermore, we weren't really checking that
declared locals weren't used before the block in which they were supposed to
appear.

src/kernel_services/ast_queries/filecheck.ml

@@ -132,10 +132,7 @@ class check ?(is_normalized=true) what : Visitor.frama_c_visitor =
            (check_abort "variables %s and %s have the same id (%d)"
               v.vname v'.vname v.vid))
       else
-        if v.vformal || v.vglob || not v.vdefined then
-          (* A defined local will only enter scope when the corresponding
-             Local_init statement is reached. *)
-          Varinfo.Hashtbl.add known_vars v v;
+        Varinfo.Hashtbl.add known_vars v v;
       match v.vlogic_var_assoc with
       | None -> Cil.DoChildren
       | Some ({ lv_origin = Some v'} as lv) when v == v' ->

tests/syntax/oracle/local-variable.res.oracle

@@ -16,6 +16,14 @@ void f(void)
   return;
 }
 
+void h(int i)
+{
+  int t[(unsigned int)100 / sizeof(x)];
+  int u[(unsigned int)100 / sizeof(i)];
+  int x = 1;
+  return;
+}
+
 int c;
 int g(void)
 {