Bug#717276: perl: enable systemtap support via -Dusedtrace

[Eric Wong]

Niko Tyni <ntyni at debian.org> wrote:
> On Thu, Jul 18, 2013 at 06:37:25PM +0000, Eric Wong wrote:
> > Source: perl
> > Severity: wishlist
> > 
> > I would like to use systemtap to trace Perl under Linux.
> > The existing dtrace support in Perl may be used for this.
> > 
> > Passing "-Dusedtrace" to Configure as documented in INSTALL
> > should enable tracing support.
> 
> Thanks for your report. I worry about possible additional overhead.
> Would it make sense to enable this only for the perl-debug build
> (/usr/bin/debugperl) ?

I think making it perl-debug is fine for the initial change.  SystemTap
does not add much (if any measurable) overhead unless it's enabled,
however.  So maybe eventually it can be in the default package.

> > A Build-Depends on systemtap-sdt-dev would be required under Linux
> 
> As a secondary concern, pushing python (which systemtap-sdt-dev
> depends on) into perl build-dependencies doesn't sound very appealing,
> but I suppose bootstrappers are used to work around those (re: the
> Build-depends-StageN effort et al.)
> 
> I assume that enabling dtrace support would not add a runtime hard
> dependency on a systemtap package?

Correct.  There's no additional linkage at runtime.
You're right, though, the python build-dep does sound kinda strange :o
Thanks for the response