Warp <war### [at] tagpovrayorg> wrote:
>   I was not talking about plans for processors. I was talking about the
> claim that *operating systems* (including linux) are going to drop support
> for the FPU even on architectures which do have a perfectly good FPU (ie.
> every single current Intel and AMD processor). I find this claim ludicrous,
> especially for linux (which aims for maximal portability).

Actually, I found this claim on the German Wikipedia article on






darauf in der Version 3.1 zu einer weiteren Umstellung, die wiederum bald



letzte ABI Wechsel erfolgte mit Version 3.4, welche auch in der aktuellen 4.x
Reihe des GCC Verwendung findet. Da die eingesetzte GCC Version von


entweder im Quelltext oder in mehreren ABI-Versionen ausgeliefert werden."

which roughly tranlsates to:


therefore it happens rather seldom. A more recent opposite example however is
the C++ ABI for the GNU C++ compiler, that first changed from version 2.95 to
version 3.0; due to errors in this new ABI it was soon followed up by another
change in version 3.1, which in turn was superseded soon after by the ABI of
version 3.2, to be compatible to other compilers like that from Intel. As it is
almost impossible to migrate the system smoothly to a new ABI, this rapid change
caused a lot of disgruntlement. The last ABI change occurred with version 3.4,
which is also used with the current 4.x versions of the GCC. As the version of
GCC employed can differ from Linux distribution to Linux distribution, C++
programs for Linux which mainly build on the GNU compiler must be distributed
either as source code or in multiple ABI versions."

So much for binary compatibility in the (x86) Linux world...


This makes sense insofar as *binary* compatibility has never been that much of
an issue in the Unix world anyway: Software has always been *expected* to need
recompiling on different machines anyway. It was only the success of "IBM
compatible (!) PCs" that started the whole binary compatibility thing anyway.

In fact, Linux runs on many, many more platforms than just x86 - maybe more than
Windows will ever dream of running on - and has been doing so almost ever since
it came to existence; so the portability in Linux always had to be achieved at
a non-binary level anyway. (And strictly speaking, portability actually only
begins where binary compatibility comes to an end.)

So all in all, thinking it over again, I don't find it too surprising to
actually see more emphasis on binary compatibility in Windows than in Linux.

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