PR gdb/14018 -- avoid "PC register not available" errors.

gdb/windows-nat.c (thread_rec): Don't display a warning when
SuspendThread fails with ERROR_ACCESS_DENIED.  If SuspendThread
fails for any reason, set th->suspended to -1, so that we don't
try to resume such a thread.  Also, don't return NULL in these
cases, to avoid completely ruin the session due to "PC register is
not available" error.
(do_windows_fetch_inferior_registers): Check errors in
GetThreadContext call.
(windows_continue): Accept an additional argument KILLED; if not
zero, ignore errors in the SetThreadContext call, since the
inferior was killed and is shutting down.
(windows_resume, get_windows_debug_event)
(windows_create_inferior, windows_mourn_inferior)
(windows_kill_inferior): All callers of windows_continue changed
to adjust to its new calling sequence.

diff --git a/gdb/ChangeLog b/gdb/ChangeLog
index fd9677bcadb7a441152193d00b4c82c0a80a3262..23ca6c09f4d8576d108a9813f6e4f5d093b1d92d 100644 (file)
--- a/gdb/ChangeLog
+++ b/gdb/ChangeLog
@@ -1,3 +1,22 @@
+2014-04-19  Eli Zaretskii  <eliz@gnu.org>
+
+       PR gdb/14018
+       * windows-nat.c (thread_rec): Don't display a warning when
+       SuspendThread fails with ERROR_ACCESS_DENIED.  If SuspendThread
+       fails for any reason, set th->suspended to -1, so that we don't
+       try to resume such a thread.  Also, don't return NULL in these
+       cases, to avoid completely ruin the session due to "PC register is
+       not available" error.
+       (do_windows_fetch_inferior_registers): Check errors in
+       GetThreadContext call.
+       (windows_continue): Accept an additional argument KILLED; if not
+       zero, ignore errors in the SetThreadContext call, since the
+       inferior was killed and is shutting down.
+       (windows_resume, get_windows_debug_event)
+       (windows_create_inferior, windows_mourn_inferior)
+       (windows_kill_inferior): All callers of windows_continue changed
+       to adjust to its new calling sequence.
+
 2014-04-19  Yao Qi  <yao@codesourcery.com>
 
        * ctf.c (ctf_open): Call post_create_inferior.

diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c
index fe40c4db142a0bd59f3f365138de7ee7ab142982..bad74086cf2dfb669564b43ba9b744147f4b6aa4 100644 (file)
--- a/gdb/windows-nat.c
+++ b/gdb/windows-nat.c
@@ -309,12 +309,18 @@ thread_rec (DWORD id, int get_context)
                  {
                    DWORD err = GetLastError ();
 
-                   warning (_("SuspendThread (tid=0x%x) failed."
-                              " (winerr %u)"),
-                            (unsigned) id, (unsigned) err);
-                   return NULL;
+                   /* We get Access Denied (5) when trying to suspend
+                      threads that Windows started on behalf of the
+                      debuggee, usually when those threads are just
+                      about to exit.  */
+                   if (err != ERROR_ACCESS_DENIED)
+                     warning (_("SuspendThread (tid=0x%x) failed."
+                                " (winerr %u)"),
+                              (unsigned) id, (unsigned) err);
+                   th->suspended = -1;
                  }
-               th->suspended = 1;
+               else
+                 th->suspended = 1;
              }
            else if (get_context < 0)
              th->suspended = -1;
@@ -444,7 +450,7 @@ do_windows_fetch_inferior_registers (struct regcache *regcache, int r)
        {
          thread_info *th = current_thread;
          th->context.ContextFlags = CONTEXT_DEBUGGER_DR;
-         GetThreadContext (th->h, &th->context);
+         CHECK (GetThreadContext (th->h, &th->context));
          /* Copy dr values from that thread.
             But only if there were not modified since last stop.
             PR gdb/2388 */
@@ -1181,10 +1187,12 @@ handle_exception (struct target_waitstatus *ourstatus)
   return 1;
 }
 
-/* Resume all artificially suspended threads if we are continuing
-   execution.  */
+/* Resume thread specified by ID, or all artificially suspended
+   threads, if we are continuing execution.  KILLED non-zero means we
+   have killed the inferior, so we should ignore weird errors due to
+   threads shutting down.  */
 static BOOL
-windows_continue (DWORD continue_status, int id)
+windows_continue (DWORD continue_status, int id, int killed)
 {
   int i;
   thread_info *th;
@@ -1212,7 +1220,16 @@ windows_continue (DWORD continue_status, int id)
          }
        if (th->context.ContextFlags)
          {
-           CHECK (SetThreadContext (th->h, &th->context));
+           DWORD ec = 0;
+
+           if (GetExitCodeThread (th->h, &ec)
+               && ec == STILL_ACTIVE)
+             {
+               BOOL status = SetThreadContext (th->h, &th->context);
+
+               if (!killed)
+                 CHECK (status);
+             }
            th->context.ContextFlags = 0;
          }
        if (th->suspended > 0)
@@ -1340,9 +1357,9 @@ windows_resume (struct target_ops *ops,
      Otherwise complain.  */
 
   if (resume_all)
-    windows_continue (continue_status, -1);
+    windows_continue (continue_status, -1, 0);
   else
-    windows_continue (continue_status, ptid_get_tid (ptid));
+    windows_continue (continue_status, ptid_get_tid (ptid), 0);
 }
 
 /* Ctrl-C handler used when the inferior is not run in the same console.  The
@@ -1560,7 +1577,7 @@ get_windows_debug_event (struct target_ops *ops,
       if (continue_status == -1)
        windows_resume (ops, minus_one_ptid, 0, 1);
       else
-       CHECK (windows_continue (continue_status, -1));
+       CHECK (windows_continue (continue_status, -1, 0));
     }
   else
     {
@@ -2337,13 +2354,13 @@ windows_create_inferior (struct target_ops *ops, char *exec_file,
 
   do_initial_windows_stuff (ops, pi.dwProcessId, 0);
 
-  /* windows_continue (DBG_CONTINUE, -1); */
+  /* windows_continue (DBG_CONTINUE, -1, 0); */
 }
 
 static void
 windows_mourn_inferior (struct target_ops *ops)
 {
-  (void) windows_continue (DBG_CONTINUE, -1);
+  (void) windows_continue (DBG_CONTINUE, -1, 0);
   i386_cleanup_dregs();
   if (open_process_used)
     {
@@ -2412,7 +2429,7 @@ windows_kill_inferior (struct target_ops *ops)
 
   for (;;)
     {
-      if (!windows_continue (DBG_CONTINUE, -1))
+      if (!windows_continue (DBG_CONTINUE, -1, 1))
        break;
       if (!WaitForDebugEvent (&current_event, INFINITE))
        break;