Re: [BUG] Memory error

[Paulo César Pereira de Andrade]

Em qui., 1 de dez. de 2022 às 13:04, Marc Nieper-Wißkirchen
<marc.nieper+gnu@gmail.com> escreveu:

  Hi,
>
> The following example causes a segmentation fault (interestingly,
> there's no segmentation fault if I remove the `jit_indirect();'
> statement).
>
> $ cat crash.c
> #include <lightning.h>
>
> int main (int argc, char *argv[])
> {
>   init_jit (argv[0]);
>   jit_state_t *_jit = jit_new_state ();
>
>   jit_prolog ();
>   jit_indirect ();
>   jit_node_t *fwd = jit_forward ();
>   jit_link (fwd);
>
>   jit_patch_at (jit_movi (JIT_R0, 0), fwd);
>   jit_retr (JIT_R0);
>   jit_epilog ();
>
>   jit_emit ();
>   jit_clear_state ();
>   jit_disassemble ();
>   jit_destroy_state ();
>   finish_jit ();
> }
> $ gcc -llightning -o crash crash.c

  Fixed in just pushed commit
https://git.savannah.gnu.org/cgit/lightning.git/commit/?id=69cbef495f947458d4d30a69f050d428ff6b1846

$  ./crash
L0: /* prolog */
    0x7f11215ed000    sub    $0x30,%rsp
    0x7f11215ed004    mov    %rbp,(%rsp)
    0x7f11215ed008    mov    %rsp,%rbp
    0x7f11215ed00b    sub    $0x18,%rsp
L1:
    0x7f11215ed00f    nop
    movi %rax 0x1cd40f0
    0x7f11215ed010    movabs $0x7f11215ed010,%rax
    retr_l %rax
     \__ movr %rax %rax
     \__ ret
L2: %rax %xmm0 /* epilog */
    0x7f11215ed01a    mov    %rbp,%rsp
    0x7f11215ed01d    mov    (%rsp),%rbp
    0x7f11215ed021    add    $0x30,%rsp
    0x7f11215ed025    ret

  But note that this is a very weird usage :)

    0x7f11215ed010    movabs $0x7f11215ed010,%rax

Thanks!
Paulo