Frama-C API - Literal_strings
 Associate literal strings to fresh varinfo.
val add : string -> Frama_c_kernel.Cil_types.varinfo -> unitval find : string -> Frama_c_kernel.Cil_types.varinfoval fold : (string -> Frama_c_kernel.Cil_types.varinfo -> 'a -> 'a) -> 'a -> 'a