[PATCH] gdbserver: When attaching, add process before lwps

Alan Hayward
2019-01-25T10:48:58Z

The recent BP/WP changes for AArch64 swapping the order in add_lwp()
so that the process was added before the lwp. This was due to the lwp
creation requiring the process data.

This also needs changing in linux_attach().

Fixes gdb.server/ext-attach.exp on Aarch64.

(This regression was hidden due to the racy nature of the gdb.server
tests - now they are no longer racy it'll be easier to spot. Also
checked X86).

gdb/gdbserver/ChangeLog:

2019-01-25 Alan Hayward <alan.hayward@arm.com>

* linux-low.c (linux_attach): Add process before lwp.
---
gdb/gdbserver/linux-low.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/gdb/gdbserver/linux-low.c b/gdb/gdbserver/linux-low.c
index 17cce24d76..1ab2cfb1eb 100644
--- a/gdb/gdbserver/linux-low.c
+++ b/gdb/gdbserver/linux-low.c
@@ -1188,6 +1188,8 @@ linux_attach (unsigned long pid)
ptid_t ptid = ptid_t (pid, pid, 0);
int err;

+ proc = linux_add_process (pid, 1);
+
/* Attach to PID. We will check for other threads
soon. */
err = linux_attach_lwp (ptid);
@@ -1198,8 +1200,6 @@ linux_attach (unsigned long pid)
error ("Cannot attach to process %ld: %s", pid, reason.c_str ());
}

- proc = linux_add_process (pid, 1);
-
/* Don't ignore the initial SIGSTOP if we just attached to this
process. It will be collected by wait shortly. */
initial_thread = find_thread_ptid (ptid_t (pid, pid, 0));
--
2.17.2 (Apple Git-113)