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[patches] Static thread debugging fixes



I've applied this patch to eglibc trunk, with Joseph's approval.  I'm
planning to backport it to the 2.5 and 2.6 branches tomorrow, after
testing there.

It fixes the GDB staticthreads.exp test case, if you have a new enough
GDB.  You need my patches from here:
  http://sourceware.org/ml/gdb-patches/2007-06/msg00479.html

That means a new snapshot of GDB, the upcoming GDB 6.7 release, or a
backport.  They should apply to any halfway recent GDB.  Mark, Joseph
suggested we update the eglibc prerequisites page on the web site; who
do I need to ask to do that?

-- 
Daniel Jacobowitz
CodeSourcery

2007-07-09  Daniel Jacobowitz  <dan@xxxxxxxxxxxxxxxx>

	Backport:
	2007-05-16  Roland McGrath  <roland@xxxxxxxxxx>
	* nptl_db/td_thr_get_info.c: Fake the results for TH->th_unique == 0.
	* nptl_db/td_thr_validate.c: Likewise.
	* nptl_db/td_thr_setgregs.c: Likewise.
	* nptl_db/td_thr_setfpregs.c: Likewise.
	* nptl_db/td_thr_getgregs.c: Likewise.
	* nptl_db/td_thr_getfpregs.c: Likewise.
	* nptl_db/td_thr_tlsbase.c: Likewise.

	* nptl_db/structs.def: Add DB_VARIABLE (__nptl_initial_report_events).
	* nptl_db/db_info.c: Add necessary declaration.
	* nptl_db/td_thr_event_enable.c: Set __nptl_initial_report_events too.

	* nptl_db/td_ta_thr_iter.c (iterate_thread_list): Make FAKE_EMPTY bool.
	Use th_unique=0 in fake descriptor before initialization.

	* nptl_db/td_ta_map_lwp2thr.c (__td_ta_lookup_th_unique): New function, broken
	out of ...
	(td_ta_map_lwp2thr): ... here, call it.  But don't before __stack_user
	is initialized, then fake a handle with th_unique=0.
	* nptl_db/thread_dbP.h: Declare it.

	* nptl/init.c (__nptl_initial_report_events): New variable.
	(__pthread_initialize_minimal_internal): Initialize pd->report_events
	to that.

Index: nptl_db/td_thr_get_info.c
===================================================================
--- nptl_db/td_thr_get_info.c	(revision 2771)
+++ nptl_db/td_thr_get_info.c	(working copy)
@@ -1,5 +1,5 @@
 /* Get thread information.
-   Copyright (C) 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+   Copyright (C) 1999,2000,2001,2002,2003,2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@xxxxxxxxxx>, 1999.
 
@@ -32,35 +32,49 @@ td_thr_get_info (const td_thrhandle_t *t
 
   LOG ("td_thr_get_info");
 
-  /* Copy the whole descriptor in once so we can access the several
-     fields locally.  Excess copying in one go is much better than
-     multiple ps_pdread calls.  */
-  err = DB_GET_STRUCT (copy, th->th_ta_p, th->th_unique, pthread);
-  if (err != TD_OK)
-    return err;
-
-  err = DB_GET_FIELD_ADDRESS (tls, th->th_ta_p, th->th_unique,
-			      pthread, specific, 0);
-  if (err != TD_OK)
-    return err;
-
-  err = DB_GET_FIELD_LOCAL (schedpolicy, th->th_ta_p, copy, pthread,
-			    schedpolicy, 0);
-  if (err != TD_OK)
-    return err;
-  err = DB_GET_FIELD_LOCAL (schedprio, th->th_ta_p, copy, pthread,
-			    schedparam_sched_priority, 0);
-  if (err != TD_OK)
-    return err;
-  err = DB_GET_FIELD_LOCAL (tid, th->th_ta_p, copy, pthread, tid, 0);
-  if (err != TD_OK)
-    return err;
-  err = DB_GET_FIELD_LOCAL (cancelhandling, th->th_ta_p, copy, pthread,
-			    cancelhandling, 0);
-  if (err != TD_OK)
-    return err;
-  err = DB_GET_FIELD_LOCAL (report_events, th->th_ta_p, copy, pthread,
-			    report_events, 0);
+  if (th->th_unique == 0)
+    {
+      /* Special case for the main thread before initialization.  */
+      copy = NULL;
+      tls = 0;
+      cancelhandling = 0;
+      schedprio = 0;
+      tid = 0;
+      err = DB_GET_VALUE (report_events, th->th_ta_p,
+			  __nptl_initial_report_events, 0);
+    }
+  else
+    {
+      /* Copy the whole descriptor in once so we can access the several
+	 fields locally.  Excess copying in one go is much better than
+	 multiple ps_pdread calls.  */
+      err = DB_GET_STRUCT (copy, th->th_ta_p, th->th_unique, pthread);
+      if (err != TD_OK)
+	return err;
+
+      err = DB_GET_FIELD_ADDRESS (tls, th->th_ta_p, th->th_unique,
+				  pthread, specific, 0);
+      if (err != TD_OK)
+	return err;
+
+      err = DB_GET_FIELD_LOCAL (schedpolicy, th->th_ta_p, copy, pthread,
+				schedpolicy, 0);
+      if (err != TD_OK)
+	return err;
+      err = DB_GET_FIELD_LOCAL (schedprio, th->th_ta_p, copy, pthread,
+				schedparam_sched_priority, 0);
+      if (err != TD_OK)
+	return err;
+      err = DB_GET_FIELD_LOCAL (tid, th->th_ta_p, copy, pthread, tid, 0);
+      if (err != TD_OK)
+	return err;
+      err = DB_GET_FIELD_LOCAL (cancelhandling, th->th_ta_p, copy, pthread,
+				cancelhandling, 0);
+      if (err != TD_OK)
+	return err;
+      err = DB_GET_FIELD_LOCAL (report_events, th->th_ta_p, copy, pthread,
+				report_events, 0);
+    }
   if (err != TD_OK)
     return err;
 
@@ -87,9 +101,10 @@ td_thr_get_info (const td_thrhandle_t *t
   infop->ti_lid = tid == 0 ? ps_getpid (th->th_ta_p->ph) : (uintptr_t) tid;
   infop->ti_traceme = report_events != 0;
 
-  err = DB_GET_FIELD_LOCAL (infop->ti_startfunc, th->th_ta_p, copy, pthread,
-			    start_routine, 0);
-  if (err == TD_OK)
+  if (copy != NULL)
+    err = DB_GET_FIELD_LOCAL (infop->ti_startfunc, th->th_ta_p, copy, pthread,
+			      start_routine, 0);
+  if (copy != NULL && err == TD_OK)
     {
       uint32_t idx;
       for (idx = 0; idx < TD_EVENTSIZE; ++idx)
Index: nptl_db/db_info.c
===================================================================
--- nptl_db/db_info.c	(revision 2771)
+++ nptl_db/db_info.c	(working copy)
@@ -1,7 +1,7 @@
 /* This file is included by pthread_create.c to define in libpthread
    all the magic symbols required by libthread_db.
 
-   Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2004, 2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -38,6 +38,8 @@ typedef struct
 
 typedef struct link_map link_map;
 
+/* Actually static in nptl/init.c, but we only need it for typeof.  */
+extern bool __nptl_initial_report_events;
 
 #define schedparam_sched_priority schedparam.sched_priority
 
Index: nptl_db/td_thr_tlsbase.c
===================================================================
--- nptl_db/td_thr_tlsbase.c	(revision 2771)
+++ nptl_db/td_thr_tlsbase.c	(working copy)
@@ -1,5 +1,5 @@
 /* Locate TLS data for a thread.
-   Copyright (C) 2003, 2006 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2006, 2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -30,8 +30,29 @@ td_thr_tlsbase (const td_thrhandle_t *th
   if (modid < 1)
     return TD_NOTLS;
 
+  psaddr_t pd = th->th_unique;
+  if (pd == 0)
+    {
+      /* This is the fake handle for the main thread before libpthread
+	 initialization.  We are using 0 for its th_unique because we can't
+	 trust that its thread register has been initialized.  But we need
+	 a real pointer to have any TLS access work.  In case of dlopen'd
+	 libpthread, initialization might not be for quite some time.  So
+	 try looking up the thread register now.  Worst case, it's nonzero
+	 uninitialized garbage and we get bogus results for TLS access
+	 attempted too early.  Tough.  */
+
+      td_thrhandle_t main_th;
+      err = __td_ta_lookup_th_unique (th->th_ta_p, ps_getpid (th->th_ta_p->ph),
+				      &main_th);
+      if (err == 0)
+	pd = main_th.th_unique;
+      if (pd == 0)
+	return TD_TLSDEFER;
+    }
+
   /* Get the DTV pointer from the thread descriptor.  */
-  err = DB_GET_FIELD (dtv, th->th_ta_p, th->th_unique, pthread, dtvp, 0);
+  err = DB_GET_FIELD (dtv, th->th_ta_p, pd, pthread, dtvp, 0);
   if (err != TD_OK)
     return err;
 
Index: nptl_db/thread_dbP.h
===================================================================
--- nptl_db/thread_dbP.h	(revision 2771)
+++ nptl_db/thread_dbP.h	(working copy)
@@ -1,5 +1,5 @@
 /* Private header for thread debug library
-   Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2004, 2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -251,4 +251,7 @@ extern td_err_e _td_store_value_local (t
 extern td_err_e _td_check_sizeof (td_thragent_t *ta, uint32_t *sizep,
 				  int sizep_name) attribute_hidden;
 
+extern td_err_e __td_ta_lookup_th_unique (const td_thragent_t *ta,
+					  lwpid_t lwpid, td_thrhandle_t *th);
+
 #endif /* thread_dbP.h */
Index: nptl_db/td_thr_setfpregs.c
===================================================================
--- nptl_db/td_thr_setfpregs.c	(revision 2771)
+++ nptl_db/td_thr_setfpregs.c	(working copy)
@@ -1,5 +1,5 @@
 /* Set a thread's floating-point register set.
-   Copyright (C) 1999, 2001, 2002, 2003 Free Software Foundation, Inc.
+   Copyright (C) 1999, 2001, 2002, 2003, 2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@xxxxxxxxxx>, 1999.
 
@@ -29,6 +29,11 @@ td_thr_setfpregs (const td_thrhandle_t *
 
   LOG ("td_thr_setfpregs");
 
+  if (th->th_unique == 0)
+    /* Special case for the main thread before initialization.  */
+    return ps_lsetfpregs (th->th_ta_p->ph, ps_getpid (th->th_ta_p->ph),
+			  fpregs) != PS_OK ? TD_ERR : TD_OK;
+
   /* We have to get the state and the PID for this thread.  */
   err = DB_GET_FIELD (cancelhandling, th->th_ta_p, th->th_unique, pthread,
 		      cancelhandling, 0);
Index: nptl_db/td_thr_getgregs.c
===================================================================
--- nptl_db/td_thr_getgregs.c	(revision 2771)
+++ nptl_db/td_thr_getgregs.c	(working copy)
@@ -1,5 +1,5 @@
 /* Get a thread's general register set.
-   Copyright (C) 1999, 2000, 2001, 2002, 2003 Free Software Foundation, Inc.
+   Copyright (C) 1999, 2000, 2001, 2002, 2003, 2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@xxxxxxxxxx>, 1999.
 
@@ -29,6 +29,11 @@ td_thr_getgregs (const td_thrhandle_t *t
 
   LOG ("td_thr_getgregs");
 
+  if (th->th_unique == 0)
+    /* Special case for the main thread before initialization.  */
+    return ps_lgetregs (th->th_ta_p->ph, ps_getpid (th->th_ta_p->ph),
+			regset) != PS_OK ? TD_ERR : TD_OK;
+
   /* We have to get the state and the PID for this thread.  */
   err = DB_GET_FIELD (cancelhandling, th->th_ta_p, th->th_unique, pthread,
 		      cancelhandling, 0);
Index: nptl_db/td_thr_setgregs.c
===================================================================
--- nptl_db/td_thr_setgregs.c	(revision 2771)
+++ nptl_db/td_thr_setgregs.c	(working copy)
@@ -1,5 +1,5 @@
 /* Set a thread's general register set.
-   Copyright (C) 1999, 2001, 2002, 2003 Free Software Foundation, Inc.
+   Copyright (C) 1999, 2001, 2002, 2003, 2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@xxxxxxxxxx>, 1999.
 
@@ -29,6 +29,11 @@ td_thr_setgregs (const td_thrhandle_t *t
 
   LOG ("td_thr_setgregs");
 
+  if (th->th_unique == 0)
+    /* Special case for the main thread before initialization.  */
+    return ps_lsetregs (th->th_ta_p->ph, ps_getpid (th->th_ta_p->ph),
+			gregs) != PS_OK ? TD_ERR : TD_OK;
+
   /* We have to get the state and the PID for this thread.  */
   err = DB_GET_FIELD (cancelhandling, th->th_ta_p, th->th_unique, pthread,
 		      cancelhandling, 0);
Index: nptl_db/td_thr_event_enable.c
===================================================================
--- nptl_db/td_thr_event_enable.c	(revision 2771)
+++ nptl_db/td_thr_event_enable.c	(working copy)
@@ -1,5 +1,5 @@
 /* Enable event process-wide.
-   Copyright (C) 1999, 2001, 2002, 2003 Free Software Foundation, Inc.
+   Copyright (C) 1999, 2001, 2002, 2003, 2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@xxxxxxxxxx>, 1999.
 
@@ -28,7 +28,25 @@ td_thr_event_enable (th, onoff)
 {
   LOG ("td_thr_event_enable");
 
-  /* Write the new value into the thread data structure.  */
-  return DB_PUT_FIELD (th->th_ta_p, th->th_unique, pthread, report_events, 0,
+  if (th->th_unique != 0)
+    {
+      /* Write the new value into the thread data structure.  */
+      td_err_e err = DB_PUT_FIELD (th->th_ta_p, th->th_unique, pthread,
+				   report_events, 0,
+				   (psaddr_t) 0 + (onoff != 0));
+      if (err != TD_OK)
+	return err;
+
+      /* Just in case we are in the window between initializing __stack_user
+	 and copying from __nptl_initial_report_events, we set it too.
+	 It doesn't hurt to do this for non-initial threads, since it
+	 won't be consulted again anyway.  It would take another fetch
+	 to get the tid and determine this isn't the initial thread,
+	 so just do it always.  */
+    }
+
+  /* We are faking it for the initial thread before its thread
+     descriptor is set up.  */
+  return DB_PUT_VALUE (th->th_ta_p, __nptl_initial_report_events, 0,
 		       (psaddr_t) 0 + (onoff != 0));
 }
Index: nptl_db/td_ta_thr_iter.c
===================================================================
--- nptl_db/td_ta_thr_iter.c	(revision 2771)
+++ nptl_db/td_ta_thr_iter.c	(working copy)
@@ -1,5 +1,6 @@
 /* Iterate over a process's threads.
-   Copyright (C) 1999,2000,2001,2002,2003,2004 Free Software Foundation, Inc.
+   Copyright (C) 1999,2000,2001,2002,2003,2004,2007
+	Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@xxxxxxxxxx>, 1999.
 
@@ -24,7 +25,7 @@
 static td_err_e
 iterate_thread_list (td_thragent_t *ta, td_thr_iter_f *callback,
 		     void *cbdata_p, td_thr_state_e state, int ti_pri,
-		     psaddr_t head, int fake_empty)
+		     psaddr_t head, bool fake_empty)
 {
   td_err_e err;
   psaddr_t next, ofs;
@@ -41,13 +42,13 @@ iterate_thread_list (td_thragent_t *ta, 
 
   if (next == 0 && fake_empty)
     {
-      /* __pthread_initialize_minimal has not run.
-	 There is just the main thread to return.  */
-      td_thrhandle_t th;
-      err = td_ta_map_lwp2thr (ta, ps_getpid (ta->ph), &th);
-      if (err == TD_OK)
-	err = callback (&th, cbdata_p) != 0 ? TD_DBERR : TD_OK;
-      return err;
+      /* __pthread_initialize_minimal has not run.  There is just the main
+	 thread to return.  We cannot rely on its thread register.  They
+	 sometimes contain garbage that would confuse us, left by the
+	 kernel at exec.  So if it looks like initialization is incomplete,
+	 we only fake a special descriptor for the initial thread.  */
+      td_thrhandle_t th = { ta, 0 };
+      return callback (&th, cbdata_p) != 0 ? TD_DBERR : TD_OK;
     }
 
   /* Cache the offset from struct pthread to its list_t member.  */
@@ -136,13 +137,15 @@ td_ta_thr_iter (const td_thragent_t *ta_
 
   err = DB_GET_SYMBOL (list, ta, __stack_user);
   if (err == TD_OK)
-    err = iterate_thread_list (ta, callback, cbdata_p, state, ti_pri, list, 1);
+    err = iterate_thread_list (ta, callback, cbdata_p, state, ti_pri,
+			       list, true);
 
   /* And the threads with stacks allocated by the implementation.  */
   if (err == TD_OK)
     err = DB_GET_SYMBOL (list, ta, stack_used);
   if (err == TD_OK)
-    err = iterate_thread_list (ta, callback, cbdata_p, state, ti_pri, list, 0);
+    err = iterate_thread_list (ta, callback, cbdata_p, state, ti_pri,
+			       list, false);
 
   return err;
 }
Index: nptl_db/td_ta_map_lwp2thr.c
===================================================================
--- nptl_db/td_ta_map_lwp2thr.c	(revision 2771)
+++ nptl_db/td_ta_map_lwp2thr.c	(working copy)
@@ -1,5 +1,5 @@
 /* Which thread is running on an LWP?
-   Copyright (C) 2003, 2004 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2004, 2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -24,8 +24,8 @@
 
 
 td_err_e
-td_ta_map_lwp2thr (const td_thragent_t *ta_arg,
-		   lwpid_t lwpid, td_thrhandle_t *th)
+__td_ta_lookup_th_unique (const td_thragent_t *ta_arg,
+			  lwpid_t lwpid, td_thrhandle_t *th)
 {
   td_thragent_t *const ta = (td_thragent_t *) ta_arg;
   ps_err_e err;
@@ -118,9 +118,6 @@ td_ta_map_lwp2thr (const td_thragent_t *
 
   switch (ta->ta_howto)
     {
-    case ta_howto_unknown:
-      return TD_DBERR;
-
     default:
       return TD_DBERR;
 
@@ -132,6 +129,7 @@ td_ta_map_lwp2thr (const td_thragent_t *
 				    0, regs, &addr);
       if (terr != TD_OK)
 	return terr;
+
       /* In this descriptor the nelem word is overloaded as the bias.  */
       addr += (int32_t) DB_DESC_NELEM (ta->ta_howto_data.reg);
       th->th_unique = addr;
@@ -143,22 +141,22 @@ td_ta_map_lwp2thr (const td_thragent_t *
       if (&ps_get_thread_area == NULL)
 	return TD_NOCAPAB;
 
-       /* A la x86-64, there is a constant magic index for get_thread_area.  */
-       if (ps_get_thread_area (ta->ph, lwpid,
-			       ta->ta_howto_data.const_thread_area,
-			       &th->th_unique) != PS_OK)
-	 return TD_ERR;	/* XXX Other error value?  */
-       break;
+      /* A la x86-64, there is a magic index for get_thread_area.  */
+      if (ps_get_thread_area (ta->ph, lwpid,
+			      ta->ta_howto_data.const_thread_area,
+			      &th->th_unique) != PS_OK)
+	return TD_ERR;	/* XXX Other error value?  */
+      break;
 
-     case ta_howto_reg_thread_area:
+    case ta_howto_reg_thread_area:
       if (&ps_get_thread_area == NULL)
 	return TD_NOCAPAB;
 
-       /* A la i386, there is a register with an index for get_thread_area.  */
-       if (ps_lgetregs (ta->ph, lwpid, regs) != PS_OK)
-	 return TD_ERR;
-       terr = _td_fetch_value_local (ta, ta->ta_howto_data.reg_thread_area, -1,
-				     0, regs, &addr);
+      /* A la i386, a register holds the index for get_thread_area.  */
+      if (ps_lgetregs (ta->ph, lwpid, regs) != PS_OK)
+	return TD_ERR;
+      terr = _td_fetch_value_local (ta, ta->ta_howto_data.reg_thread_area,
+				    -1, 0, regs, &addr);
       if (terr != TD_OK)
 	return terr;
       /* In this descriptor the nelem word is overloaded as scale factor.  */
@@ -172,7 +170,40 @@ td_ta_map_lwp2thr (const td_thragent_t *
     }
 
   /* Found it.  Now complete the `td_thrhandle_t' object.  */
-  th->th_ta_p = (td_thragent_t *) ta;
+  th->th_ta_p = ta;
 
   return TD_OK;
 }
+
+td_err_e
+td_ta_map_lwp2thr (const td_thragent_t *ta_arg,
+		   lwpid_t lwpid, td_thrhandle_t *th)
+{
+  td_thragent_t *const ta = (td_thragent_t *) ta_arg;
+
+  /* We cannot rely on thread registers and such information at all
+     before __pthread_initialize_minimal has gotten far enough.  They
+     sometimes contain garbage that would confuse us, left by the kernel
+     at exec.  So if it looks like initialization is incomplete, we only
+     fake a special descriptor for the initial thread.  */
+
+  psaddr_t list;
+  td_err_e err = DB_GET_SYMBOL (list, ta, __stack_user);
+  if (err != TD_OK)
+    return err;
+
+  err = DB_GET_FIELD (list, ta, list, list_t, next, 0);
+  if (err != TD_OK)
+    return err;
+
+  if (list == 0)
+    {
+      if (ps_getpid (ta->ph) != lwpid)
+	return TD_ERR;
+      th->th_ta_p = ta;
+      th->th_unique = 0;
+      return TD_OK;
+    }
+
+  return __td_ta_lookup_th_unique (ta_arg, lwpid, th);
+}
Index: nptl_db/structs.def
===================================================================
--- nptl_db/structs.def	(revision 2771)
+++ nptl_db/structs.def	(working copy)
@@ -1,5 +1,5 @@
 /* List of types and symbols in libpthread examined by libthread_db.
-   Copyright (C) 2003, 2006 Free Software Foundation, Inc.
+   Copyright (C) 2003, 2006, 2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -56,6 +56,7 @@ DB_FUNCTION (__nptl_death_event)
 DB_SYMBOL (__nptl_threads_events)
 DB_VARIABLE (__nptl_nthreads)
 DB_VARIABLE (__nptl_last_event)
+DB_VARIABLE (__nptl_initial_report_events)
 
 DB_ARRAY_VARIABLE (__pthread_keys)
 DB_STRUCT (pthread_key_struct)
Index: nptl_db/td_thr_getfpregs.c
===================================================================
--- nptl_db/td_thr_getfpregs.c	(revision 2771)
+++ nptl_db/td_thr_getfpregs.c	(working copy)
@@ -1,5 +1,5 @@
 /* Get a thread's floating-point register set.
-   Copyright (C) 1999, 2001, 2002, 2003 Free Software Foundation, Inc.
+   Copyright (C) 1999, 2001, 2002, 2003, 2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@xxxxxxxxxx>, 1999.
 
@@ -29,6 +29,11 @@ td_thr_getfpregs (const td_thrhandle_t *
 
   LOG ("td_thr_getfpregs");
 
+  if (th->th_unique == 0)
+    /* Special case for the main thread before initialization.  */
+    return ps_lgetfpregs (th->th_ta_p->ph, ps_getpid (th->th_ta_p->ph),
+			  regset) != PS_OK ? TD_ERR : TD_OK;
+
   /* We have to get the state and the PID for this thread.  */
   err = DB_GET_FIELD (cancelhandling, th->th_ta_p, th->th_unique, pthread,
 		      cancelhandling, 0);
Index: nptl_db/td_thr_validate.c
===================================================================
--- nptl_db/td_thr_validate.c	(revision 2771)
+++ nptl_db/td_thr_validate.c	(working copy)
@@ -1,5 +1,5 @@
 /* Validate a thread handle.
-   Copyright (C) 1999, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+   Copyright (C) 1999,2001,2002,2003,2004,2007 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@xxxxxxxxxx>, 1999.
 
@@ -75,16 +75,10 @@ td_thr_validate (const td_thrhandle_t *t
       if (err == TD_OK)
 	err = check_thread_list (th, list, &uninit);
 
-      if (err == TD_NOTHR && uninit)
-	{
-	  /* __pthread_initialize_minimal has not run yet.
-	     But the main thread still has a valid ID.  */
-	  td_thrhandle_t main_th;
-	  err = td_ta_map_lwp2thr (th->th_ta_p,
-				   ps_getpid (th->th_ta_p->ph), &main_th);
-	  if (err == TD_OK && th->th_unique != main_th.th_unique)
-	    err = TD_NOTHR;
-	}
+      if (err == TD_NOTHR && uninit && th->th_unique == 0)
+	/* __pthread_initialize_minimal has not run yet.
+	   There is only the special case thread handle.  */
+	err = TD_OK;
     }
 
   return err;
Index: nptl/init.c
===================================================================
--- nptl/init.c	(revision 2771)
+++ nptl/init.c	(working copy)
@@ -234,6 +234,9 @@ sighandler_setxid (int sig, siginfo_t *s
 extern void **__libc_dl_error_tsd (void) __attribute__ ((const));
 
 
+/* This can be set by the debugger before initialization is complete.  */
+static bool __nptl_initial_report_events;
+
 void
 __pthread_initialize_minimal_internal (void)
 {
@@ -297,6 +300,9 @@ __pthread_initialize_minimal_internal (v
   INIT_LIST_HEAD (&__stack_user);
   list_add (&pd->list, &__stack_user);
 
+  /* Before initializing __stack_user, the debugger could not find us and
+     had to set __nptl_initial_report_events.  Propagate its setting.  */
+  THREAD_SETMEM (pd, report_events, __nptl_initial_report_events);
 
   /* Install the cancellation signal handler.  If for some reason we
      cannot install the handler we do not abort.  Maybe we should, but