From 17617f2d366ca969ccbc784be4f75931a1afd20f Mon Sep 17 00:00:00 2001 From: Eli Zaretskii Date: Sat, 19 Apr 2014 11:12:19 +0300 Subject: [PATCH] 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. --- gdb/ChangeLog | 19 +++++++++++++++++++ gdb/windows-nat.c | 49 +++++++++++++++++++++++++++++++++---------------- 2 files changed, 52 insertions(+), 16 deletions(-) diff --git a/gdb/ChangeLog b/gdb/ChangeLog index fd9677b..23ca6c0 100644 --- a/gdb/ChangeLog +++ b/gdb/ChangeLog @@ -1,3 +1,22 @@ +2014-04-19 Eli Zaretskii + + 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 * ctf.c (ctf_open): Call post_create_inferior. diff --git a/gdb/windows-nat.c b/gdb/windows-nat.c index fe40c4d..bad7408 100644 --- 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 (¤t_event, INFINITE)) break; -- 2.7.4