Re: Uninitialized SCM variables

[Reinhold Kainhofer]

Am Wednesday, 17. August 2011, 13:53:40 schrieb Carl Sorensen:
> \On 8/16/11 10:25 PM, "Dan Eble" <address@hidden> wrote:
> > Is there a reason that these variables in lily/profile.cc don't need to
> > be initialized?  I don't have experience with guile, but it looks
> > dangerous.
> > 
> > SCM context_property_lookup_table;
> > SCM grob_property_lookup_table;
> > SCM prob_property_lookup_table;
> 
> I guess the code in this section relies on the fact that the compiler will
> initialize the unitialized value to zero.   Do you believe that is a
> problem?

Note that this is also the assumption on the !cached, even if changed to use 
SCM_UNPACK:

SCM cached;
if (!SCM_UNPACK (cached)) ...

where SCM_UNPACK is defined in /usr/include/libguile/tags.h to be either
   #define SCM_UNPACK(x) (x)
or
   #define SCM_UNPACK(x) ((x).n.n)

In both cases, the check is whether an uninitialized variable is 0...

Cheers,
Reinhold

-- 
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Reinhold Kainhofer, address@hidden, http://reinhold.kainhofer.com/
 * Financial & Actuarial Math., Vienna Univ. of Technology, Austria
 * http://www.fam.tuwien.ac.at/, DVR: 0005886
 * LilyPond, Music typesetting, http://www.lilypond.org