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Multiboot problem
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Date: -- (:)
From: David LONY <david.lony@p...>
Subject: Multiboot problem
Hi all,

I'm currently trying to make a multiboot sector with ocaml code. 
Unfortunately, it doesn't work bu I don't know why...
To do that, I made a small program in ocaml :

let test_char a = a+1
let _ = Callback.register "caml_test_char" test_char;;

I also made a dummy libc  (all functions return 0 or NULL pointer) 
because I have to provide all these functions if a wants to statically 
link a C objects..
This is my main file with the entry point of the kernel :

/* Include definitions of the multiboot standard */
#include <multiboot.h>
#include <x86_videomem.h>
#include <caml/mlvalues.h>
#include <caml/callback.h>

/* This is the entry point of the kernel */
void sos_main(unsigned long magic, unsigned long addr)
  static char * argv[]={ "ocaml", NULL };

  multiboot_info_t *mbi;

  /* Retrieve grub information (memory...etc) */
  mbi = (multiboot_info_t *) addr;
  /* Clean the screen and put a 'A' on it */
  sos_x86_videomem_putchar(1, 0, SOS_X86_VIDEO_FG_WHITE | 
  /* An operatig system never ends */
  for (;;)


But qemu freezes when I call the caml_startup function (If I removed it, 
it works well...)...Perhaps the caml_startup function relies on C 
function that I don't implements ?
If someone have an idea.... Because I must call this function 
(caml_startup) in order to call my ocaml function (test_char)...

Thanks a lot.
David LONY