Re: Issue 5732: Use unique_ptr in layout code (issue 573500043 by address@hidden)

[dak]

On 2020/02/03 18:27:27, dak wrote:
> On 2020/02/03 18:13:00, hahnjo wrote:
> > On 2020/02/03 18:01:09, dak wrote:
> > > Stupid question: unique_ptr has the purpose of deallocating memory
when the
> > last
> > > reference is gone.  But we have an entire Scheme allocation system
exactly
> for
> > > that purpose for which we are already paying the price in
overhead.  Any
> > chance
> > > this can be usefully tracked in the SCM scheme of things?
> > 
> > Why would we want to use GC more than needed? Any marking algorithm
will
> always
> > be slower than a local variable going out of scope.
> 
> unique_ptr has bookkeeping overhead.  The marking algorithm runs
anyway and has
> no memory overhead.  I have not looked at the actual patch yet, but
unique_ptr
> really is doing pretty much the same job as SCM except that it acts
with no
> delay, so if it is important that the destructors are called right
away when the
> last reference is gone, SCM will not do the job.

Sorry, I confused this with shared_ptr.  unique_ptr just has compilation
overhead, no runtime or memory overhead.  Nothing to be seen here, I
withdraw my objection.  This is definitely not something where SCM would
solve the same task.

https://codereview.appspot.com/573500043/