Rust updates

[Walter Bright]

On 7/8/2012 6:49 AM, bearophile wrote:
> I think in Go the function stack is segmented and growable as in Go. This saves
> RAM if you need a small stack, and avoids stack overflows where lot of stack is
> needed.

The trouble with segmented stacks are:

1. they have a significant runtime penalty

2. interfacing to C code becomes problematic


Also, they do not save RAM, they save address space. RAM is not committed until 
a stack memory page is actually used.

Segmented stacks are useful for 32 bit address space. However, they are not 
useful for 64 bit address spaces. Heck, you can allocate 4 billion stacks of 4 
billion bytes each! (Remember, allocating address space is not allocating actual 
memory.)

Given that the programming world is moving rapidly to 64 bit exclusively, I 
think segmented stacks are a dead end technology. They would have been much more 
interesting 15 years ago.