Re: [MIT-Scheme-devel] Attempted Clean-up of Mac OS X MIT Scheme Port

[Jed Davis]

Chris Hanson wrote:

> This is unfortunately hard to fix, because the current implementation
> wants a large block of memory below 0x04000000.  MacOS X apparently uses
> that part of the address space for other things.  A similar problem
> happens in some GNU/Linux distributions, and also on Windows systems.

The trick for Mac OS X is to link with -Wl,-pagezero_size,04000000 (or
however much space is needed).  This sets the size of the PROT_NONE area
at the bottom of virtual memory that traps null pointer accesses; the
linker will, necessarily, place all other load commands above it.  Then,
one can mmap over it with MAP_FIXED, since it doesn't contain anything
whose loss would be a problem.

-- 
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((lambda (r) ((C C) (lambda (s) (r (lambda l (apply (s s) l))))))  (lambda
(f) (lambda (l) (if (null? l) C (lambda (k) (display (car l)) ((f (cdr l))
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