GDB: Work around D;PID handling bug in older GDBservers (PR gdb/23377)

This commit adds a GDB workaround for the GDBserver bug exposed by
commit f2ffa92bbce9 ("gdb: Eliminate the 'stop_pc' global"), so that
newer GDBs can continue working with older GDBservers.

gdb/ChangeLog:
2018-07-11  Pedro Alves  <palves@redhat.com>

	PR gdb/23377
	* remote.c (remote_target::remote_detach_pid): Call
	set_current_process.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index f36edde..7b77e87 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,9 @@
+2018-07-11  Pedro Alves  <palves@redhat.com>
+
+       PR gdb/23377
+       * remote.c (remote_target::remote_detach_pid): Call
+       set_current_process.
+
 2018-07-11  Sergio Durigan Junior  <sergiodj@redhat.com>
 
        PR c++/23373

diff --git a/gdb/remote.c b/gdb/remote.c
index d5accc6..9a5286d 100644 (file)
--- a/gdb/remote.c
+++ b/gdb/remote.c
@@ -5628,6 +5628,14 @@ remote_target::remote_detach_pid (int pid)
 {
   struct remote_state *rs = get_remote_state ();
 
+  /* This should not be necessary, but the handling for D;PID in
+     GDBserver versions prior to 8.2 incorrectly assumes that the
+     selected process points to the same process we're detaching,
+     leading to misbehavior (and possibly GDBserver crashing) when it
+     does not.  Since it's easy and cheap, work around it by forcing
+     GDBserver to select GDB's current process.  */
+  set_general_process ();
+
   if (remote_multi_process_p (rs))
     xsnprintf (rs->buf, get_remote_packet_size (), "D;%x", pid);
   else