Custom Query (1030 matches)

​http://clozure.com/pipermail/openmcl-devel/2011-January/012498.html

describes a problem which affected someone running ARM Linux. It's not clear what Linux versions and architectures are affected.

Traditionally, Linux maps in pages of the initial thread's control/C stack as they're touched. The new (or at least previously unobserved) behavior involves the kernel not mapping a page that would be adjacent to another mapped region (like the guard page region that CCL uses to detect stack overflow) and causes the stack limit check in the recursive marker to fail.

I think that the simplest fix is likely to ensure that all pages between the stack area's softlimit and current sp are mapped read-write, so that the kernel's lazy faulting-in of stack pages doesn't try to exercise policy.

I tried to run win32 binary in Windows 7 64-bit. but an exception occurred.

this is log.

$ ./wx86cl
%eax = 0x02403058
%ecx = 0x000005ec
%edx = 0x00000008
%ebx = 0xc0000005
%esp = 0x02402de0
%ebp = 0x02403038
%esi = 0x02403060
%edi = 0x024030b4
%eip = 0x00023c95
%eflags = 0x00010202

%cs = 0x0023
%ds = 0x002b
%ss = 0x002b
%es = 0x002b
%fs = 0x0053
%gs = 0x002b
Exception on foreign stack

Exception occurred while executing foreign code
? for help
[4148] Clozure CL kernel debugger: 

What I was trying to do is to declare a function inline. That function has a macro inside. Depending on whether I declaim it inline or notinline I get two different outcomes.

Well I assume that we always should get the same outcome (semantically) independent of whether we declaim something inline or notinline.

Here's a demo:

(in-package :cl-user)

(defpackage :test
  (:use :cl))

(in-package :test)

(defmacro foo ()
  `(funcall ',(intern "FOOBAR")))

(defun foobar ()
  42)

(declaim (inline bar))
(defun bar ()
  (foo))

(in-package :cl-user)

(defun busted ()
  (test::bar))

;; Just for information...
(find-symbol "FOOBAR")			; => FOOBAR, :INTERNAL

;; Error!
(busted)

;;; Lets try it with bar not being inlined.
;;; =======================================

(in-package :test)

(declaim (notinline bar))
(defun bar ()
  (foo))

(in-package :cl-user)

(unintern 'foobar)			; GC that

(defun busted ()
  (test::bar))

;; Runs fine this time.
(busted)

;; Just for information...
(find-symbol "FOOBAR")			; => NIL, NIL