Do not detach from tracee which experienced ptrace error.

Before this patch, if a thread got nuked by exit in another thread
and we happened to poke it at the same time, we print "????(" thingy
and detach the thread. Since we removed "detach before death" logic,
this no longer matches the behavior of other threads.
Before patch:
[pid  1780] exit_group(1)               = ?
[pid  1778] ????( <unfinished ...>
Process 1778 detached
[pid  5860] +++ exited with 1 +++
After:
[pid 17765] exit_group(1)               = ?
[pid 21680] ????( <unfinished ...>
[pid 17791] +++ exited with 1 +++
[pid 21680] +++ exited with 1 +++

* strace (trace): Do not detach from tracee which experienced ptrace error.

Signed-off-by: Denys Vlasenko <dvlasenk@redhat.com>
1 file changed