Call xalloc only when argc > 0.
Call xalloc only when argc > 0.

To clean "passing arg # of `foo' as signed/unsigned due to prototype".

schuyler/sqlite3-ruby,duhlin/sqlite3-ruby,duhlin/sqlite3-ruby,alexdowad/sqlite3-ruby,yoshimoto/sqlite3-ruby,AutogrowSystems/sqlite3-ruby,simplegeo/sqlite3-ruby,yoshimoto/sqlite3-ruby,simplegeo/sqlite3-ruby,schuyler/sqlite3-ruby,schuyler/sqlite3-ruby,AutogrowSystems/sqlite3-ruby,alexdowad/sqlite3-ruby