[Rd] alloca() on FreeBSD (PR#7890)

[vangyzen@stat.duke.edu]

Prof. Ripley:

I apologize for my lack of response.  I just moved halfway across the US 
and have had little to no connectivity for the past two weeks.  :(

Thanks to you and Rainer Hurling for fixing this.

Eric

Prof Brian Ripley wrote:
> On Mon, 23 May 2005 vangyzen at stat.duke.edu wrote:
> 
>> Full_Name: Eric van Gyzen
>> Version: 2.1.0
>> OS: FreeBSD 5.4
>> Submission from: (NULL) (152.3.22.33)
>>
>>
>> R-2.1.0 fails to compile on the newest release of FreeBSD, complaining 
>> about
>> undefined references to __builtin_alloca.  On FreeBSD, alloca() is 
>> declared in
>> stdlib.h, not alloca.h as the R sources expect.  Therefore, 
>> HAVE_DECL_ALLOCA
>> does not get set, so the R sources declare alloca() after it has 
>> already been
>> #defined by stdlib.h.
>>
>> A possible fix is to modify the configure script to look for the 
>> declaration of
>> alloca() in stdlib.h (perhaps after it fails to find it in alloca.h).
> 
> 
> It is already supposed to, so it is not finding the declaration there 
> either. If you look up the definition of
> 
> AC_CHECK_DECLS([alloca], , , [#include <alloca.h>])
> 
> it searches in stdlib.h.  Can you please send us the appropriate part of 
> config.log?  It may be that this is failing because alloca.h is not found
> (but AC_FUNC_ALLOCA is making the same assumptions).
> 
> Perhaps the easiest way out is to override the setting on FreeBSD: can 
> you please confirm that manually changing
> 
> #define HAVE_DECL_ALLOCA 1
> 
> in config.h works?
> 
>> This was previously reported in PR#7881.
> 
> 
> So please don't open a new report on the subject!
>