[Cryptography] GCC bug 30475 (was Re: bounded pointers in C)

[Bear]

On Thu, 2014-05-01 at 12:50 -0400, Jerry Leichter wrote:

> As I mentioned before, Java originally specified FP arithmetic this
> tightly - and as a result compliant, reasonably efficient
> implementations were *impossible* on tons of hardware.  The Java
> community eventually backed off because this was an issue for so much
> of what they decided was the Java audience; but when it comes to other
> forms of integer arithmetic, they've effectively written off multiple
> classes of machines.

At this point it's hard to say that C's treatment of such things 
as 'undefined' is better.  Having semantics that can't be known 
or checked is nearly as bad as working on a "written off" class
of hardware.

Given the history of bugs, I would rather have a language be 
cripplingly slow on some hardware (doing all math via emulation, 
yuck!) than have important parts of mathematical semantics 
unknown, unknowable, or unenforceable on all hardware.  If I 
want to use Java on a 1's complement machine, performance will 
suck but it'll have no math-related bugs that it didn't have 
on the original.  

			Bear