Re: [PATCH 1/2] gdb: Convert completion tracker to use std types

[Tom Tromey <tom at tromey dot com>]

>>>>> "Andrew" == Andrew Burgess <andrew.burgess@embecosm.com> writes:

Andrew> For now then I'm holding the raw 'char *' within the unordered_map,
Andrew> and rely on the completion_tracker object to delete the data if
Andrew> needed, or to ensure that the data is passed over to readline, which
Andrew> will do the deletion for us.

Seems reasonable enough.

Andrew> +  for (const auto &p : m_entries_hash)
Andrew> +    {
Andrew> +      xfree ((char *) p.first);
Andrew> +      xfree ((char *) p.second);

Maybe const_cast would be better?

Andrew> +  /* A map of completions.  The key is the completion, and the value is the
Andrew> +     string to be used to compute the lowest common denominator.  Both the
Andrew> +     key and the value are owned by the completion_tracker class while
Andrew> +     being held in this map, as such completion_tracker must free these
Andrew> +     strings when finished with them, or pass ownership to someone else who
Andrew> +     will free them.  */
Andrew> +  typedef std::unordered_map<const char *, const char *, std::hash<std::string>,
Andrew> +			     std::equal_to<std::string>> completion_set;

Does using std::string here mean that a temporary std::string will be
made for each insertion in the map?  And also for comparisons?
That seems expensive if so.

Tom