On Sun, Jun 03, 2007 at 08:00:18AM -0700, Bernhard Schmalhofer via RT wrote:
> I have looked at the 'more_memory.patch' and I'm wondering about the > portability. > In that patch loops where pointers are explicitly set to NULL > are replaced with a > memset( start, 0, len); > > What happens when NULL is not a consective series of '\0' chars? I think that it breaks. > Are there such platforms and are they releavant for parrot? I believe that this assumption is endemic in Perl 5, and it's never hindered Perl 5's portability. The C FAQ gives examples of platforms where NULL is not all bits zero - http://c-faq.com/null/machexamp.html - and I've never encountered anyone using them. (As an aside, I think that Perl 5 also (mostly?) doesn't assume 2s complement storage of integers. IIRC a bug report from a Ahmdal mainframes gave the impression that it was using sign and magnitude. However, we've not heard about anyone using Ahmdal mainframes in years. Likewise no-one has missed the removal of memory model support from Configure, so presumably no-one is compiling on a PDP-11 anymore. We did discover nasal daemons, or something similarly painful, on Irix64, until we removed assumptions about signed integer overflow. (It's undefined behaviour. It will bite)) Nicholas Clark
