[PATCH v3] libdwfl/linux-pid-attach.c PR33974: __libdwfl_set_initial_registers_thread on non-Linux

[Sam James]

Serhei Makarov <serhei@serhei.io> writes:

> libdwfl_stacktrace uses __libdwfl_set_initial_registers_thread but it
> is wrapped by #ifdef __linux__, causing build errors on non-Linux
> platforms.
>
> * linux-pid-attach.c (__libdwfl_set_initial_registers_thread):
>   Remove from inside the '#ifdef __linux__'.
> * dwfl_frame_regs.c (__libdwfl_set_initial_registers_thread):
>   Move here.

I have no opinion on the design of the fix so I won't say I've reviewed
it.

Tested-by: Sam James <sam@gentoo.org>

Thank you!

> ---
>  libdwfl/dwfl_frame_regs.c  | 27 +++++++++++++++++++++++++++
>  libdwfl/linux-pid-attach.c | 25 -------------------------
>  2 files changed, 27 insertions(+), 25 deletions(-)
>
> diff --git a/libdwfl/dwfl_frame_regs.c b/libdwfl/dwfl_frame_regs.c
> index 572ac676..99de3c22 100644
> --- a/libdwfl/dwfl_frame_regs.c
> +++ b/libdwfl/dwfl_frame_regs.c
> @@ -77,3 +77,30 @@ dwfl_frame_reg (Dwfl_Frame *state, unsigned regno, Dwarf_Word *val)
>    return res;
>  }
>  INTDEF(dwfl_frame_reg)
> +
> +/* Implement the ebl_set_initial_registers_tid setfunc callback.  */
> +
> +bool
> +/* Not internal_function, since that allows calling-convention changes
> +   e.g. on i386, and stable ABI is needed to use this as an
> +   ebl_tid_registers_t * callback in linux-pid-attach.c and
> +   libdwfl_stacktrace.  */
> +__libdwfl_set_initial_registers_thread (int firstreg, unsigned nregs,
> +				   const Dwarf_Word *regs, void *arg)
> +{
> +  Dwfl_Thread *thread = (Dwfl_Thread *) arg;
> +  if (firstreg == -1)
> +    {
> +      assert (nregs == 1);
> +      INTUSE(dwfl_thread_state_register_pc) (thread, *regs);
> +      return true;
> +    }
> +  else if (firstreg == -2)
> +    {
> +      assert (nregs == 1);
> +      INTUSE(dwfl_thread_state_registers) (thread, firstreg, nregs, regs);
> +      return true;
> +     }
> +  assert (nregs > 0);
> +  return INTUSE(dwfl_thread_state_registers) (thread, firstreg, nregs, regs);
> +}
> diff --git a/libdwfl/linux-pid-attach.c b/libdwfl/linux-pid-attach.c
> index a6e4e41a..9472b041 100644
> --- a/libdwfl/linux-pid-attach.c
> +++ b/libdwfl/linux-pid-attach.c
> @@ -302,31 +302,6 @@ pid_getthread (Dwfl *dwfl __attribute__ ((unused)), pid_t tid,
>    return true;
>  }
>  
> -/* Implement the ebl_set_initial_registers_tid setfunc callback.  */
> -
> -bool
> -/* XXX No internal_function annotation,
> -   as this function gets passed as ebl_tid_registers_t *.  */
> -__libdwfl_set_initial_registers_thread (int firstreg, unsigned nregs,
> -				   const Dwarf_Word *regs, void *arg)
> -{
> -  Dwfl_Thread *thread = (Dwfl_Thread *) arg;
> -  if (firstreg == -1)
> -    {
> -      assert (nregs == 1);
> -      INTUSE(dwfl_thread_state_register_pc) (thread, *regs);
> -      return true;
> -    }
> -  else if (firstreg == -2)
> -    {
> -      assert (nregs == 1);
> -      INTUSE(dwfl_thread_state_registers) (thread, firstreg, nregs, regs);
> -      return true;
> -     }
> -  assert (nregs > 0);
> -  return INTUSE(dwfl_thread_state_registers) (thread, firstreg, nregs, regs);
> -}
> -
>  static bool
>  pid_set_initial_registers (Dwfl_Thread *thread, void *thread_arg)
>  {
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 418 bytes
Desc: not available
URL: <https://sourceware.org/pipermail/elfutils-devel/attachments/20260318/f0ebedad/attachment.sig>