On Mon, 28 Oct 2013 11:13:38 +0100, Mark Wielaard wrote:
On Sun, 2013-10-27 at 15:29 +0100, Jan Kratochvil wrote:
> Valgrind would always warn if the application did not set it. Even if the
> appplication never used it. It would warn on lines:
> if (! process->callbacks->set_initial_registers (thread,
> thread->callbacks_arg))
> process->callbacks->thread_detach (thread, thread->callbacks_arg);
>
> as CALLBACKS_ARG is passed there by value, not by reference.
BTW. If you configure --with-valgrind then make check runs all tests
under valgrind.
--enable-valgrind
It fails on:
backtrace: backtrace.c:445: selfdump: Assertion `plt != ((void *)0)' failed.
The testcase looks a bit at some ELF internals... Maybe the testcase could
use some asm volatile () instead of adapting to what compiler produced.
I don't think valgrind memcheck would warn in the above case for
passing
around "undefined values". It only warns when those undefined bits are
actually used in a condition or end up being passed as syscall arguments
it knows should have defined values.
OK, you are right, I did not expect that. It can safely pass undefined values
in registers.
Thanks,
Jan