Re: [gentoo-dev] Introduce global dmalloc USE flag?

[Gilles Dartiguelongue <eva@gentoo.org>]

Le lundi 24 juin 2013 à 12:05 +0300, Samuli Suominen a écrit :
> On 24/06/13 11:54, Gilles Dartiguelongue wrote:
> > Le samedi 22 juin 2013 à 15:48 +0800, Dennis Lan (dlan) a écrit :
> >> On Fri, Jun 21, 2013 at 2:34 AM, Ian Stakenvicius <axs@gentoo.org> wrote:
> >>> -----BEGIN PGP SIGNED MESSAGE-----
> >>> Hash: SHA256
> >>>
> >>> On 13/06/13 01:05 AM, Michał Górny wrote:
> >>>> Dnia 2013-06-13, o godz. 09:35:54 "Dennis Lan (dlan)"
> >>>> <dennis.yxun@gmail.com> napisał(a):
> >>>>
> >>>>> also 4) app-admin/conserver 5) net-nds/ypbind 6) net-fs/samba 7)
> >>>>> net-analyzer/scli 8) net-analyzer/traceproto 6) net-misc/siproxd
> >>>>>
> >>>>> use dmalloc but controlled under USE=debug
> >>>>
> >>>> Do those use USE=debug solely for dmalloc or does it imply other
> >>>> stuff? Therefore: will it be possible to use USE=dmalloc in those
> >>>> packages?
> >>
> >> HI mgorny, as I look into those ebuilds
> >> all of them use the USE=debug flag for dmalloc only, not for other
> >> debugging control
> >> so, as your second question, of course it's possible to switch to USE=dmalloc
> >>
> >>>>
> >>>
> >>> and to follow up, if we assume that USE="debug" does more than just
> >>> build the package against the dmalloc lib (which is likely), is there
> >>
> >> Yes, if this case exist.. then the separation would be good
> >>
> >>
> >>> any particular benefit to USE="debug -dmalloc" ?  Or USE="dmalloc
> >>> - -debug" ?
> >>>
> >>
> >> I'm not sure, probably the befefits would be that we can have more
> >> accurate/explicit control,
> >> USE="dmalloc" is for debugging memory usage stuff (allocation, free,
> >> fence-post overwritten control)
> >> and USE=debug for other stuff?
> >>
> >> This is a slightly improvement, but I'm also totally fine to keep
> >> current state as it is.. no big deal
> >
> > Reading this thread, looks to me like these dmalloc USE should be moved
> > to debug, unless it has no runtime impact on usual speed, etc.
> >
> 
> It does. In most often cases building against dmalloc makes the 
> application/library completely unusable, and building it against dmalloc 
> is intended for the developer of the application.
> Separated USE=dmalloc is the only sane way to approach it.

To be clear, the justification of USE=dmalloc being separated from
USE=debug is that it is so "intrusive" than anyone excepts a developer
would find it too cumbersome to attempt to debug a problem with the
application ?

If that is the case, maybe the USE flag description should mention that
so it is not enabled lightly.

-- 
Gilles Dartiguelongue <eva@gentoo.org>
Gentoo