[R] problems with for: warnings and segfault

[Prof Brian Ripley]

On Fri, 11 Nov 2005, Peter Dalgaard wrote:

> Mike Miller <mbmiller at taxa.epi.umn.edu> writes:
>
>> On Fri, 11 Nov 2005, Ronaldo Reis-Jr. wrote:
>>
>>> Segmentation fault
>>>
>>> This is a R bug or an error in my for function?
>>
>>
>> All seg faults are bugs.
>
> Within reason... If users go out of their way to cause havoc, e.g.
> calling C/Fortran entry points with incorrect parameters, they deserve
> what they get. "Normal" abuse of the language shouldn't crash R.

Also, they are not necessarily bugs *in R*.  They could well be bugs in 
the compiler or the libc (or equivalent) or even the OS running out of 
resources ungracefully.  We've seen quite a few which were compiler bugs, 
and cases where a malloc failure was a segfault in the OS and not
a NULL return.

This one was a bug in R, only happening with incorrect usage.  It has now 
been fixed.

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595