C4::Search::GetSearchHistory does not work, as it contains a SQL syntax error: SELECT FROM search_history WHERE... Its broken state is not visible to users, however, because that routine is not used -- opac-search-history.pl is doing a direct SQL query, which is not ideal. GetSearchHistory should be fixed, then put in use.
Note that I remove this routine in bug 10807.
I confirm that the routine was removed.