[R-pkg-team] Bug#980809: Matrix package default tolerance on s390x (Re: Bug#980809: rmatrix: breaks autopkgtest of r-cran-glmmtmb on s390x)

[Graham Inggs]

Hi Dirk

On Wed, 17 Feb 2021 at 15:10, Dirk Eddelbuettel <edd at debian.org> wrote:
> Graham:  What does that bigendian box say for   Sys.info()[["machine"]]   ?

The other big-endian box I tested was perotto.debian.net [*], it says:

> Sys.info()[["machine"]]
[1] "ppc64"

> Should we test for endianness instead?  And then maybe try to roll up to the
> cause of the difference?

I've just tested on 32-bit big-endian and the glmmTMB problem does not
occur there, so at this stage I would say test for big-endian **and**
64 bits.

Just to be clear, is the fix you are proposing in Matrix going to fix
the glmmTMB error?

If a bug shows up on 64-bit big-endian, but not on little-endian or
32-bit big-endian, then it's usually a sign that somewhere a 64-bit
variable is incorrectly being read or written to as a 32-bit variable.

Regards
Graham


[*] https://db.debian.org/machines.cgi?sortby=purpose&sortorder=dsc