[gclist] why malloc/free instead of GC?

Fergus Henderson fjh@cs.mu.OZ.AU
Wed, 19 Feb 2003 15:10:46 +1100


On 18-Feb-2003, Basile STARYNKEVITCH <basile@starynkevitch.net> wrote:
> For completeness and shameless plug I also hacked the same (useless)
> program to use my Qish generational copying GC - see
> http://freshmeat.net/projects/qish for details on Qish.

IIRC, qish depends on GCC's `-fvolatile' and `-fvolatile-globals' options,
right?

Firstly, because of this, it's not really fair to compare just GC
times, since qish will have a significant overhead on code which
does not do any allocation at all.  So benchmarks which do allocation
but have little or no computation (referencing global variables,
dereferencing pointers, etc.) will unfairly advantage qish.

Secondly, you may be interested to know that these options (or at least
`-fvolatile-globals' -- I'm not 100% sure about `-fvolatile') have been
removed from the CVS sources for GCC, because they were broken in GCC
versions 3.0 and beyond.  So this may cause trouble for Qish.

-- 
Fergus Henderson <fjh@cs.mu.oz.au>  |  "I have always known that the pursuit
The University of Melbourne         |  of excellence is a lethal habit"
WWW: <http://www.cs.mu.oz.au/~fjh>  |     -- the last words of T. S. Garp.