let prop_const mem = function
| CInt64(k,_,_) ->
if k = Int64.zero then F.p_false else F.p_true
| CChr c ->
if c ='0' then F.p_false else F.p_true
| CReal(f,_,_) ->
if f = 0.0 then F.p_false else F.p_true
| CEnum e ->
!prop_rec mem e.eival
| CWStr _ ->
WpLog.not_yet_implemented "wide character string constant"
| CStr s ->
WpLog.not_yet_implemented "character string constant (%S)" s