The vforkdone stop reply misses indicating the thread ID of the vfork
parent which the event relates to:
@cindex vfork events, remote reply
@item vfork
The packet indicates that @code{vfork} was called, and @var{r}
is the thread ID of the new child process. Refer to
@ref{thread-id syntax} for the format of the @var{thread-id}
field. This packet is only applicable to targets that support
vfork events.
@cindex vforkdone events, remote reply
@item vforkdone
The packet indicates that a child process created by a vfork
has either called @code{exec} or terminated, so that the
address spaces of the parent and child process are no longer
shared. The @var{r} part is ignored. This packet is only
applicable to targets that support vforkdone events.
Unfortunately, this is not just a documentation issue. GDBserver
is really not specifying the thread ID. I noticed because
in non-stop mode, gdb complains:
[Thread 6089.6089] #1 stopped.
#0 0x0000003615a011f0 in ?? ()
0x0000003615a011f0 in ?? ()
(gdb) set debug remote 1
(gdb) c
Continuing.
Sending packet: $QPassSignals:e;10;14;17;1a;1b;1c;21;24;25;2c;4c;#5f...Packet received: OK
Sending packet: $vCont;c:p17c9.17c9#88...Packet received: OK
Notification received: Stop:T05vfork:p17ce.17ce;06:40d7ffffff7f0000;07:30d7ffffff7f0000;10:e4c9eb1536000000;thread:p17c9.17c9;core:2;
Sending packet: $vStopped#55...Packet received: OK
Sending packet: $D;17ce#af...Packet received: OK
Sending packet: $vCont;c:p17c9.17c9#88...Packet received: OK
Notification received: Stop:T05vforkdone:;
No process or thread specified in stop reply: T05vforkdone:;
(gdb)
This is not non-stop-mode-specific, however. Consider e.g., that in
all-stop, you may be debugging more than one process at the same time.
You continue, and both processes vfork. So when you next get a
T05vforkdone, there's no way to tell which of the parent processes is
done with the vfork.
Tests will be added later.
Tested on x86_64 Fedora 20.
gdb/ChangeLog:
2015-09-15 Pedro Alves <palves@redhat.com>
PR remote/18965
* remote-utils.c (prepare_resume_reply): Merge
TARGET_WAITKIND_VFORK_DONE switch case with the
TARGET_WAITKIND_FORKED case.
gdb/doc/ChangeLog:
2015-09-15 Pedro Alves <palves@redhat.com>
PR remote/18965
* gdb.texinfo (Stop Reply Packets): Explain that vforkdone's 'r'
part indicates the thread ID of the parent process.
8228463cbc
