svn commit: r268566 - head/usr.bin/users

[Alexander Nasonov]

Joerg Sonnenberger wrote:
> On Sat, Jul 12, 2014 at 09:34:28PM +1000, Bruce Evans wrote:
> > Run time:
> > C++ sort() was twice as slow as qsort() for sorting 1 million dummy
> > users in the allocation tests.  About 8 seconds instead of 4, except
> > when compiled with -g -O0 it was 15 seconds instead of 4.
> 
> I find that claim strange and not reproducable. In my tests, std::sort
> tends to be significant faster than qsort. Attached is a small test
> program that for me is twice as fast for sorting integers...

Integers are faster indeed but I'm not sure about used-defined
types like basic_string<CharT,TraitsT,AllocT>. qsort uses 3-way
comparison while std::sort always uses less_than (a<b) and !(a<b).
The compiler can optimize when a and b are integers but not when
they're user-defined types with a user-defined comparison function.

Alex