[m-rev.] diff: fix segmentation fault in runtime on Mac OS X

[Julien Fischer]

Hi Peter,

On Thu, 26 Jun 2014, Peter Wang wrote:

> What a mess.

Indeed.  (Although not quite as bad as trying to get the Unicode version
of the argument vector on Windows.)

> Presumably all libraries other the glibc provide the standard
> strerror_r, so the patch below should be less fragile.

features.h is not a standard header, so the patch below is simply
likely to break on systems that don't provide it (i.e. my laptop).

> Or we can try to #define the right macros so glibc always provides the
> standard version.

That's unfortunately also rather brittle, because you can't rely on
users not stuffing around with the C compiler flags.

Cheers,
Julien.