Re: PATCH: Merge objc-improvements-branch to mainline

[Kaelin Colclasure]

On Thursday, September 25, 2003, at 07:56  AM, Jason Merrill wrote:

> On Thu, 25 Sep 2003 11:41:33 +0200, Dietmar Planitzer 
> <dave.pl@ping.at> wrote:
>
> > On Thursday, September 25, 2003, at 01:55  AM, Nicolas Roard wrote:
> > The current macro based exception implementation has at least two
> > significant disadvantages: (1) it is unsafe and (2) very inefficient 
> > on
> > RISC CPUs.
>
> Unfortunately, it seems that the implementation being discussed only 
> solves
> #1.

True -- but this is because Apple has a widely deployed installed base 
of code which uses the "legacy" library-based exceptions. If they're 
ever to change this, it has to happen incrementally. By making the 
first generation of compiler-supported exceptions interoperable with 
the library (while simultaneously changing the library macros to now 
use the compiler support for new code), the necessary preconditions for 
eventually replacing uses of the legacy library-based exceptions are in 
place.

<friendly-jab>
Unlike Red Hat, Apple can't indulge in the luxury of just telling all 
their customers to recompile all their code to move it to their new OS 
release. :-)
</friendly-jab>

-- Kaelin