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Date: Sun, 24 May 2009 20:27:00 -0000
Message-ID: <e394668d0905241327l7790a531l9cd003fcae1ee809@mail.gmail.com>
Subject: [RFA] Fix build failure [was Re: [RFC] fork in multi-threaded apps,  	per-thread pending_fork, other follow-fork cleanups.]
From: Doug Evans <dje@google.com>
To: Pedro Alves <pedro@codesourcery.com>
Cc: gdb-patches@sourceware.org
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On Sun, May 24, 2009 at 11:01 AM, Pedro Alves <pedro@codesourcery.com> wrot=
e:
> [...]
> We're not worse than before, so I checked in this revision of that
> patch with a few extra comments and small cleanups.
>
> --
> Pedro Alves
>
> gdb/
> 2009-05-24 =A0Pedro Alves =A0<pedro@codesourcery.com>
>
> =A0 =A0 =A0 =A0* gdbthread.h (struct thread_info): New `pending_follow' f=
ield.
> =A0 =A0 =A0 =A0* thread.c (new_thread): New function.
> =A0 =A0 =A0 =A0(add_thread_silent): Use it.
> =A0 =A0 =A0 =A0* breakpoint.c (internal_breakpoint_number): New global, m=
oved
> =A0 =A0 =A0 =A0from inside...
> =A0 =A0 =A0 =A0(create_internal_breakpoint): ... this.
> =A0 =A0 =A0 =A0(clone_momentary_breakpoint): New.
> =A0 =A0 =A0 =A0* breakpoint.h (clone_momentary_breakpoint): Declare.
> =A0 =A0 =A0 =A0* infrun.c (nullify_last_target_wait_ptid): Move declarati=
on
> =A0 =A0 =A0 =A0higher.
> =A0 =A0 =A0 =A0(pending_follow): Delete.
> =A0 =A0 =A0 =A0(follow_fork): Handle pending follow fork event here. =A0M=
oved the
> =A0 =A0 =A0 =A0preserving of thread stepping state here.
> =A0 =A0 =A0 =A0(resume): Don't handle pending follow fork events here. =
=A0Only
> =A0 =A0 =A0 =A0install the inferior's terminal modes if we're about to re=
sume it.
> =A0 =A0 =A0 =A0(proceed): Handle possible pending follow fork events here.
> =A0 =A0 =A0 =A0(init_wait_for_inferior): No need to clear pending_follow =
anymore,
> =A0 =A0 =A0 =A0it's gone.
> =A0 =A0 =A0 =A0(handle_inferior_event): Adjust to per-thread `pending_fol=
low'.
> =A0 =A0 =A0 =A0Call `follow_fork' to handle following the fork. =A0If the
> =A0 =A0 =A0 =A0follow-fork is cancelled, stop stepping.
> =A0 =A0 =A0 =A0* linux-nat.c (linux_child_follow_fork): Adjust to per-thr=
ead
> =A0 =A0 =A0 =A0`pending_follow' events. =A0Remove code that handled prese=
rving the
> =A0 =A0 =A0 =A0thread stepping state.
> =A0 =A0 =A0 =A0* inf-ptrace.c (inf_ptrace_follow_fork): Ditto.
> =A0 =A0 =A0 =A0* inf-ttrace.c (inf_ttrace_follow_fork): Ditto.
>
> gdb/testsuite/
> 2009-05-24 =A0Pedro Alves =A0<pedro@codesourcery.com>
>
> =A0 =A0 =A0 =A0* gdb.threads/fork-thread-pending.c: New.
> =A0 =A0 =A0 =A0* gdb.threads/fork-thread-pending.exp: New.
>
> ---
> =A0gdb/breakpoint.c =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0| =A0 40 +++
> =A0gdb/breakpoint.h =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0| =A0 =A02
> =A0gdb/gdbthread.h =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 | =A0 =A05
> =A0gdb/inf-ptrace.c =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0| =A0 36 ---
> =A0gdb/inf-ttrace.c =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0| =A0 44 ----
> =A0gdb/infrun.c =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0| =A0241 ++++++++++++++++------
> =A0gdb/linux-nat.c =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 | =A0 37 ---
> =A0gdb/testsuite/gdb.threads/fork-thread-pending.c =A0 | =A0109 +++++++++
> =A0gdb/testsuite/gdb.threads/fork-thread-pending.exp | =A0128 +++++++++++
> =A0gdb/thread.c =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =
=A0 =A0 =A0 =A0 =A0| =A0 37 ++-
> =A010 files changed, 508 insertions(+), 171 deletions(-)
>
> Index: src/gdb/gdbthread.h
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> --- src.orig/gdb/gdbthread.h =A0 =A02009-05-21 23:45:24.000000000 +0100
> +++ src/gdb/gdbthread.h 2009-05-24 17:09:03.000000000 +0100
> @@ -165,6 +165,11 @@ struct thread_info
> =A0 =A0 =A0next time inferior stops if it stops due to stepping. =A0*/
> =A0 int step_multi;
>
> + =A0/* This is used to remember when a fork or vfork event was caught by
> + =A0 =A0 a catchpoint, and thus the event is to be followed at the next
> + =A0 =A0 resume of the thread, and not immediately. =A0*/
> + =A0struct target_waitstatus pending_follow;
> +
> =A0 /* Last signal that the inferior received (why it stopped). =A0*/
> =A0 enum target_signal stop_signal;
>
> Index: src/gdb/thread.c
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> --- src.orig/gdb/thread.c =A0 =A0 =A0 2009-05-21 23:45:24.000000000 +0100
> +++ src/gdb/thread.c =A0 =A02009-05-24 17:14:18.000000000 +0100
> @@ -141,6 +141,28 @@ init_thread_list (void)
> =A0 thread_list =3D NULL;
> =A0}
>
> +/* Allocate a new thread with target id PTID and add it to the thread
> + =A0 list. =A0*/
> +
> +static struct thread_info *
> +new_thread (ptid_t ptid)
> +{
> + =A0struct thread_info *tp;
> +
> + =A0tp =3D xcalloc (1, sizeof (*tp));
> +
> + =A0tp->ptid =3D ptid;
> + =A0tp->num =3D ++highest_thread_num;
> + =A0tp->next =3D thread_list;
> + =A0thread_list =3D tp;
> +
> + =A0/* Nothing to follow yet. =A0*/
> + =A0tp->pending_follow.kind =3D TARGET_WAITKIND_SPURIOUS;
> + =A0tp->state_ =3D THREAD_STOPPED;
> +
> + =A0return tp;
> +}
> +
> =A0struct thread_info *
> =A0add_thread_silent (ptid_t ptid)
> =A0{
> @@ -162,12 +184,7 @@ add_thread_silent (ptid_t ptid)
>
> =A0 =A0 =A0 if (ptid_equal (inferior_ptid, ptid))
> =A0 =A0 =A0 =A0{
> - =A0 =A0 =A0 =A0 tp =3D xmalloc (sizeof (*tp));
> - =A0 =A0 =A0 =A0 memset (tp, 0, sizeof (*tp));
> - =A0 =A0 =A0 =A0 tp->ptid =3D minus_one_ptid;
> - =A0 =A0 =A0 =A0 tp->num =3D ++highest_thread_num;
> - =A0 =A0 =A0 =A0 tp->next =3D thread_list;
> - =A0 =A0 =A0 =A0 thread_list =3D tp;
> + =A0 =A0 =A0 =A0 tp =3D new_thread (ptid);
>
> =A0 =A0 =A0 =A0 =A0/* Make switch_to_thread not read from the thread. =A0=
*/
> =A0 =A0 =A0 =A0 =A0tp->state_ =3D THREAD_EXITED;
> @@ -191,13 +208,7 @@ add_thread_silent (ptid_t ptid)
> =A0 =A0 =A0 =A0delete_thread (ptid);
> =A0 =A0 }
>
> - =A0tp =3D (struct thread_info *) xmalloc (sizeof (*tp));
> - =A0memset (tp, 0, sizeof (*tp));
> - =A0tp->ptid =3D ptid;
> - =A0tp->num =3D ++highest_thread_num;
> - =A0tp->next =3D thread_list;
> - =A0thread_list =3D tp;
> -
> + =A0tp =3D new_thread (ptid);
> =A0 observer_notify_new_thread (tp);
>
> =A0 return tp;
> Index: src/gdb/breakpoint.c
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> --- src.orig/gdb/breakpoint.c =A0 2009-05-23 18:24:43.000000000 +0100
> +++ src/gdb/breakpoint.c =A0 =A0 =A0 =A02009-05-24 17:18:54.000000000 +01=
00
> @@ -1456,10 +1456,11 @@ reattach_breakpoints (int pid)
> =A0 return 0;
> =A0}
>
> +static int internal_breakpoint_number =3D -1;
> +
> =A0static struct breakpoint *
> =A0create_internal_breakpoint (CORE_ADDR address, enum bptype type)
> =A0{
> - =A0static int internal_breakpoint_number =3D -1;
> =A0 struct symtab_and_line sal;
> =A0 struct breakpoint *b;
>
> @@ -5007,6 +5008,43 @@ set_momentary_breakpoint (struct symtab_
> =A0 return b;
> =A0}
>
> +/* Make a deep copy of momentary breakpoint ORIG. =A0Returns NULL if
> + =A0 ORIG is NULL. =A0*/
> +
> +struct breakpoint *
> +clone_momentary_breakpoint (struct breakpoint *orig)
> +{
> + =A0struct breakpoint *copy;
> +
> + =A0/* If there's nothing to clone, then return nothing. =A0*/
> + =A0if (orig =3D=3D NULL)
> + =A0 =A0return NULL;
> +
> + =A0copy =3D set_raw_breakpoint_without_location (orig->type);
> + =A0copy->loc =3D allocate_bp_location (copy);
> + =A0set_breakpoint_location_function (copy->loc);
> +
> + =A0copy->loc->requested_address =3D orig->loc->requested_address;
> + =A0copy->loc->address =3D orig->loc->address;
> + =A0copy->loc->section =3D orig->loc->section;
> +
> + =A0if (orig->source_file =3D=3D NULL)
> + =A0 =A0copy->source_file =3D NULL;
> + =A0else
> + =A0 =A0copy->source_file =3D xstrdup (orig->source_file);
> +
> + =A0copy->line_number =3D orig->line_number;
> + =A0copy->frame_id =3D orig->frame_id;
> + =A0copy->thread =3D orig->thread;
> +
> + =A0copy->enable_state =3D bp_enabled;
> + =A0copy->disposition =3D disp_donttouch;
> + =A0copy->number =3D internal_breakpoint_number--;
> +
> + =A0update_global_location_list_nothrow (0);
> + =A0return copy;
> +}
> +
> =A0struct breakpoint *
> =A0set_momentary_breakpoint_at_pc (CORE_ADDR pc, enum bptype type)
> =A0{
> Index: src/gdb/breakpoint.h
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> --- src.orig/gdb/breakpoint.h =A0 2009-05-21 23:45:24.000000000 +0100
> +++ src/gdb/breakpoint.h =A0 =A0 =A0 =A02009-05-24 17:09:03.000000000 +01=
00
> @@ -696,6 +696,8 @@ extern struct breakpoint *set_momentary_
> =A0extern struct breakpoint *set_momentary_breakpoint_at_pc
> =A0 (CORE_ADDR pc, enum bptype type);
>
> +extern struct breakpoint *clone_momentary_breakpoint (struct breakpoint =
*bpkt);
> +
> =A0extern void set_ignore_count (int, int, int);
>
> =A0extern void set_default_breakpoint (int, CORE_ADDR, struct symtab *, i=
nt);
> Index: src/gdb/infrun.c
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> --- src.orig/gdb/infrun.c =A0 =A0 =A0 2009-05-24 17:02:20.000000000 +0100
> +++ src/gdb/infrun.c =A0 =A02009-05-24 17:13:31.000000000 +0100
> @@ -83,6 +83,8 @@ static int prepare_to_proceed (int);
>
> =A0void _initialize_infrun (void);
>
> +void nullify_last_target_wait_ptid (void);
> +
> =A0/* When set, stop the 'step' command if we enter a function which has
> =A0 =A0no line number information. =A0The normal behavior is that we step
> =A0 =A0over such function. =A0*/
> @@ -255,21 +257,6 @@ void init_thread_stepping_state (struct
>
> =A0void init_infwait_state (void);
>
> -/* This is used to remember when a fork or vfork event was caught by a
> - =A0 catchpoint, and thus the event is to be followed at the next resume
> - =A0 of the inferior, and not immediately. =A0*/
> -static struct
> -{
> - =A0enum target_waitkind kind;
> - =A0struct
> - =A0{
> - =A0 =A0ptid_t parent_pid;
> - =A0 =A0ptid_t child_pid;
> - =A0}
> - =A0fork_event;
> -}
> -pending_follow;
> -
> =A0static const char follow_fork_mode_child[] =3D "child";
> =A0static const char follow_fork_mode_parent[] =3D "parent";
>
> @@ -290,12 +277,157 @@ Debugger response to a program call of f
> =A0}
>
>
> +/* Tell the target to follow the fork we're stopped at. =A0Returns true
> + =A0 if the inferior should be resumed; false, if the target for some
> + =A0 reason decided it's best not to resume. =A0*/
> +
> =A0static int
> =A0follow_fork (void)
> =A0{
> =A0 int follow_child =3D (follow_fork_mode_string =3D=3D follow_fork_mode=
_child);
> + =A0int should_resume =3D 1;
> + =A0struct thread_info *tp;
> +
> + =A0/* Copy user stepping state to the new inferior thread. =A0FIXME: the
> + =A0 =A0 followed fork child thread should have a copy of most of the
> + =A0 =A0 parent thread structure's run control related fields, not just
> + =A0 =A0 these. =A0*/
> + =A0struct breakpoint *step_resume_breakpoint;
> + =A0CORE_ADDR step_range_start;
> + =A0CORE_ADDR step_range_end;
> + =A0struct frame_id step_frame_id;
> +
> + =A0if (!non_stop)
> + =A0 =A0{
> + =A0 =A0 =A0ptid_t wait_ptid;
> + =A0 =A0 =A0struct target_waitstatus wait_status;
> +
> + =A0 =A0 =A0/* Get the last target status returned by target_wait(). =A0=
*/
> + =A0 =A0 =A0get_last_target_status (&wait_ptid, &wait_status);
> +
> + =A0 =A0 =A0/* If not stopped at a fork event, then there's nothing else=
 to
> + =A0 =A0 =A0 =A0do. =A0*/
> + =A0 =A0 =A0if (wait_status.kind !=3D TARGET_WAITKIND_FORKED
> + =A0 =A0 =A0 =A0 && wait_status.kind !=3D TARGET_WAITKIND_VFORKED)
> + =A0 =A0 =A0 return 1;
> +
> + =A0 =A0 =A0/* Check if we switched over from WAIT_PTID, since the event=
 was
> + =A0 =A0 =A0 =A0reported. =A0*/
> + =A0 =A0 =A0if (!ptid_equal (wait_ptid, minus_one_ptid)
> + =A0 =A0 =A0 =A0 && !ptid_equal (inferior_ptid, wait_ptid))
> + =A0 =A0 =A0 {
> + =A0 =A0 =A0 =A0 /* We did. =A0Switch back to WAIT_PTID thread, to tell =
the
> + =A0 =A0 =A0 =A0 =A0 =A0target to follow it (in either direction). =A0We=
'll
> + =A0 =A0 =A0 =A0 =A0 =A0afterwards refuse to resume, and inform the user=
 what
> + =A0 =A0 =A0 =A0 =A0 =A0happened. =A0*/
> + =A0 =A0 =A0 =A0 switch_to_thread (wait_ptid);
> + =A0 =A0 =A0 =A0 should_resume =3D 0;
> + =A0 =A0 =A0 }
> + =A0 =A0}
> +
> + =A0tp =3D inferior_thread ();
> +
> + =A0/* If there were any forks/vforks that were caught and are now to be
> + =A0 =A0 followed, then do so now. =A0*/
> + =A0switch (tp->pending_follow.kind)
> + =A0 =A0{
> + =A0 =A0case TARGET_WAITKIND_FORKED:
> + =A0 =A0case TARGET_WAITKIND_VFORKED:
> + =A0 =A0 =A0{
> + =A0 =A0 =A0 ptid_t parent, child;
> +
> + =A0 =A0 =A0 /* If the user did a next/step, etc, over a fork call,
> + =A0 =A0 =A0 =A0 =A0preserve the stepping state in the fork child. =A0*/
> + =A0 =A0 =A0 if (follow_child && should_resume)
> + =A0 =A0 =A0 =A0 {
> + =A0 =A0 =A0 =A0 =A0 step_resume_breakpoint
> + =A0 =A0 =A0 =A0 =A0 =A0 =3D clone_momentary_breakpoint (tp->step_resume=
_breakpoint);
> + =A0 =A0 =A0 =A0 =A0 step_range_start =3D tp->step_range_start;
> + =A0 =A0 =A0 =A0 =A0 step_range_end =3D tp->step_range_end;
> + =A0 =A0 =A0 =A0 =A0 step_frame_id =3D tp->step_frame_id;
> +
> + =A0 =A0 =A0 =A0 =A0 /* For now, delete the parent's sr breakpoint, othe=
rwise,
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0parent/child sr breakpoints are considered d=
uplicates,
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0and the child version will not be installed.=
 =A0Remove
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0this when the breakpoints module becomes awa=
re of
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0inferiors and address spaces. =A0*/
> + =A0 =A0 =A0 =A0 =A0 delete_step_resume_breakpoint (tp);
> + =A0 =A0 =A0 =A0 =A0 tp->step_range_start =3D 0;
> + =A0 =A0 =A0 =A0 =A0 tp->step_range_end =3D 0;
> + =A0 =A0 =A0 =A0 =A0 tp->step_frame_id =3D null_frame_id;
> + =A0 =A0 =A0 =A0 }
> +
> + =A0 =A0 =A0 parent =3D inferior_ptid;
> + =A0 =A0 =A0 child =3D tp->pending_follow.value.related_pid;
> +
> + =A0 =A0 =A0 /* Tell the target to do whatever is necessary to follow
> + =A0 =A0 =A0 =A0 =A0either parent or child. =A0*/
> + =A0 =A0 =A0 if (target_follow_fork (follow_child))
> + =A0 =A0 =A0 =A0 {
> + =A0 =A0 =A0 =A0 =A0 /* Target refused to follow, or there's some other =
reason
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0we shouldn't resume. =A0*/
> + =A0 =A0 =A0 =A0 =A0 should_resume =3D 0;
> + =A0 =A0 =A0 =A0 }
> + =A0 =A0 =A0 else
> + =A0 =A0 =A0 =A0 {
> + =A0 =A0 =A0 =A0 =A0 /* This pending follow fork event is now handled, o=
ne way
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0or another. =A0The previous selected thread =
may be gone
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0from the lists by now, but if it is still ar=
ound, need
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0to clear the pending follow request. =A0*/
> + =A0 =A0 =A0 =A0 =A0 tp =3D find_thread_pid (parent);
> + =A0 =A0 =A0 =A0 =A0 if (tp)
> + =A0 =A0 =A0 =A0 =A0 =A0 tp->pending_follow.kind =3D TARGET_WAITKIND_SPU=
RIOUS;
> +
> + =A0 =A0 =A0 =A0 =A0 /* This makes sure we don't try to apply the "Switc=
hed
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0over from WAIT_PID" logic above. =A0*/
> + =A0 =A0 =A0 =A0 =A0 nullify_last_target_wait_ptid ();
> +
> + =A0 =A0 =A0 =A0 =A0 /* If we followed the child, switch to it... */
> + =A0 =A0 =A0 =A0 =A0 if (follow_child)
> + =A0 =A0 =A0 =A0 =A0 =A0 {
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 switch_to_thread (child);
> +
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 /* ... and preserve the stepping state, in =
case the
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0user was stepping over the fork call=
. =A0*/
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 if (should_resume)
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 {
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 tp =3D inferior_thread ();
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 tp->step_resume_breakpoint =3D step=
_resume_breakpoint;
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 tp->step_range_start =3D step_range=
_start;
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 tp->step_range_end =3D step_range_e=
nd;
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 tp->step_frame_id =3D step_frame_id;
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 }
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 else
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 {
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 /* If we get here, it was because w=
e're trying to
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0resume from a fork catchpoin=
t, but, the user
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0has switched threads away fr=
om the thread that
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0forked. =A0In that case, the=
 resume command
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0issued is most likely not ap=
plicable to the
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0child, so just warn, and ref=
use to resume. =A0*/
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 warning (_("\
> +Not resuming: switched threads before following fork child.\n"));
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 }
> +
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 /* Reset breakpoints in the child as approp=
riate. =A0*/
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 follow_inferior_reset_breakpoints ();
> + =A0 =A0 =A0 =A0 =A0 =A0 }
> + =A0 =A0 =A0 =A0 =A0 else
> + =A0 =A0 =A0 =A0 =A0 =A0 switch_to_thread (parent);
> + =A0 =A0 =A0 =A0 }
> + =A0 =A0 =A0}
> + =A0 =A0 =A0break;
> + =A0 =A0case TARGET_WAITKIND_SPURIOUS:
> + =A0 =A0 =A0/* Nothing to follow. =A0*/
> + =A0 =A0 =A0break;
> + =A0 =A0default:
> + =A0 =A0 =A0internal_error (__FILE__, __LINE__,
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 "Unexpected pending_follow.kind=
 %d\n",
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0 tp->pending_follow.kind);
> + =A0 =A0 =A0break;
> + =A0 =A0}
>
> - =A0return target_follow_fork (follow_child);
> + =A0return should_resume;
> =A0}
>
> =A0void
> @@ -987,8 +1119,6 @@ resume (int step, enum target_signal sig
> =A0{
> =A0 int should_resume =3D 1;
> =A0 struct cleanup *old_cleanups =3D make_cleanup (resume_cleanups, 0);
> -
> - =A0/* Note that these must be reset if we follow a fork below. =A0*/
> =A0 struct regcache *regcache =3D get_current_regcache ();
> =A0 struct gdbarch *gdbarch =3D get_regcache_arch (regcache);
> =A0 struct thread_info *tp =3D inferior_thread ();
> @@ -1058,31 +1188,6 @@ a command like `return' or `jump' to con
> =A0 if (step)
> =A0 =A0 step =3D maybe_software_singlestep (gdbarch, pc);
>
> - =A0/* If there were any forks/vforks/execs that were caught and are
> - =A0 =A0 now to be followed, then do so. =A0*/
> - =A0switch (pending_follow.kind)
> - =A0 =A0{
> - =A0 =A0case TARGET_WAITKIND_FORKED:
> - =A0 =A0case TARGET_WAITKIND_VFORKED:
> - =A0 =A0 =A0pending_follow.kind =3D TARGET_WAITKIND_SPURIOUS;
> - =A0 =A0 =A0if (follow_fork ())
> - =A0 =A0 =A0 should_resume =3D 0;
> -
> - =A0 =A0 =A0/* Following a child fork will change our notion of current
> - =A0 =A0 =A0 =A0thread. =A0*/
> - =A0 =A0 =A0tp =3D inferior_thread ();
> - =A0 =A0 =A0regcache =3D get_current_regcache ();
> - =A0 =A0 =A0gdbarch =3D get_regcache_arch (regcache);
> - =A0 =A0 =A0pc =3D regcache_read_pc (regcache);
> - =A0 =A0 =A0break;
> -
> - =A0 =A0default:
> - =A0 =A0 =A0break;
> - =A0 =A0}
> -
> - =A0/* Install inferior's terminal modes. =A0*/
> - =A0target_terminal_inferior ();
> -
> =A0 if (should_resume)
> =A0 =A0 {
> =A0 =A0 =A0 ptid_t resume_ptid;
> @@ -1164,6 +1269,9 @@ a command like `return' or `jump' to con
> =A0 =A0 =A0 =A0 =A0 displaced_step_dump_bytes (gdb_stdlog, buf, sizeof (b=
uf));
> =A0 =A0 =A0 =A0 }
>
> + =A0 =A0 =A0/* Install inferior's terminal modes. =A0*/
> + =A0 =A0 =A0target_terminal_inferior ();
> +
> =A0 =A0 =A0 /* Avoid confusing the next resume, if the next stop/resume
> =A0 =A0 =A0 =A0 happens to apply to another thread. =A0*/
> =A0 =A0 =A0 tp->stop_signal =3D TARGET_SIGNAL_0;
> @@ -1305,12 +1413,26 @@ prepare_to_proceed (int step)
> =A0void
> =A0proceed (CORE_ADDR addr, enum target_signal siggnal, int step)
> =A0{
> - =A0struct regcache *regcache =3D get_current_regcache ();
> - =A0struct gdbarch *gdbarch =3D get_regcache_arch (regcache);
> + =A0struct regcache *regcache;
> + =A0struct gdbarch *gdbarch;
> =A0 struct thread_info *tp;
> - =A0CORE_ADDR pc =3D regcache_read_pc (regcache);
> + =A0CORE_ADDR pc;
> =A0 int oneproc =3D 0;
>
> + =A0/* If we're stopped at a fork/vfork, follow the branch set by the
> + =A0 =A0 "set follow-fork-mode" command; otherwise, we'll just proceed
> + =A0 =A0 resuming the current thread. =A0*/
> + =A0if (!follow_fork ())
> + =A0 =A0{
> + =A0 =A0 =A0/* The target for some reason decided not to resume. =A0*/
> + =A0 =A0 =A0normal_stop ();
> + =A0 =A0 =A0return;
> + =A0 =A0}
> +
> + =A0regcache =3D get_current_regcache ();
> + =A0gdbarch =3D get_regcache_arch (regcache);
> + =A0pc =3D regcache_read_pc (regcache);
> +
> =A0 if (step > 0)
> =A0 =A0 step_start_function =3D find_pc_function (pc);
> =A0 if (step < 0)
> @@ -1517,9 +1639,6 @@ init_wait_for_inferior (void)
>
> =A0 breakpoint_init_inferior (inf_starting);
>
> - =A0/* The first resume is not following a fork/vfork/exec. */
> - =A0pending_follow.kind =3D TARGET_WAITKIND_SPURIOUS; =A0 =A0 =A0/* I.e.=
, none. */
> -
> =A0 clear_proceed_status ();
>
> =A0 stepping_past_singlestep_breakpoint =3D 0;
> @@ -1698,8 +1817,6 @@ infrun_thread_stop_requested (ptid_t pti
> =A0 iterate_over_threads (infrun_thread_stop_requested_callback, &ptid);
> =A0}
>
> -void nullify_last_target_wait_ptid (void);
> -
> =A0static void
> =A0infrun_thread_thread_exit (struct thread_info *tp, int silent)
> =A0{
> @@ -2407,10 +2524,6 @@ handle_inferior_event (struct execution_
> =A0 =A0 case TARGET_WAITKIND_VFORKED:
> =A0 =A0 =A0 if (debug_infrun)
> =A0 =A0 =A0 =A0 fprintf_unfiltered (gdb_stdlog, "infrun: TARGET_WAITKIND_=
FORKED\n");
> - =A0 =A0 =A0pending_follow.kind =3D ecs->ws.kind;
> -
> - =A0 =A0 =A0pending_follow.fork_event.parent_pid =3D ecs->ptid;
> - =A0 =A0 =A0pending_follow.fork_event.child_pid =3D ecs->ws.value.relate=
d_pid;
>
> =A0 =A0 =A0 if (!ptid_equal (ecs->ptid, inferior_ptid))
> =A0 =A0 =A0 =A0{
> @@ -2439,6 +2552,11 @@ handle_inferior_event (struct execution_
> =A0 =A0 =A0 =A0 =A0detach_breakpoints (child_pid);
> =A0 =A0 =A0 =A0}
>
> + =A0 =A0 =A0/* In case the event is caught by a catchpoint, remember that
> + =A0 =A0 =A0 =A0the event is to be followed at the next resume of the th=
read,
> + =A0 =A0 =A0 =A0and not immediately. =A0*/
> + =A0 =A0 =A0ecs->event_thread->pending_follow =3D ecs->ws;
> +
> =A0 =A0 =A0 stop_pc =3D regcache_read_pc (get_thread_regcache (ecs->ptid)=
);
>
> =A0 =A0 =A0 ecs->event_thread->stop_bpstat =3D bpstat_stop_status (stop_p=
c, ecs->ptid);
> @@ -2448,8 +2566,19 @@ handle_inferior_event (struct execution_
> =A0 =A0 =A0 /* If no catchpoint triggered for this, then keep going. =A0*/
> =A0 =A0 =A0 if (ecs->random_signal)
> =A0 =A0 =A0 =A0{
> + =A0 =A0 =A0 =A0 int should_resume;
> +
> =A0 =A0 =A0 =A0 =A0ecs->event_thread->stop_signal =3D TARGET_SIGNAL_0;
> - =A0 =A0 =A0 =A0 keep_going (ecs);
> +
> + =A0 =A0 =A0 =A0 should_resume =3D follow_fork ();
> +
> + =A0 =A0 =A0 =A0 ecs->event_thread =3D inferior_thread ();
> + =A0 =A0 =A0 =A0 ecs->ptid =3D inferior_ptid;
> +
> + =A0 =A0 =A0 =A0 if (should_resume)
> + =A0 =A0 =A0 =A0 =A0 keep_going (ecs);
> + =A0 =A0 =A0 =A0 else
> + =A0 =A0 =A0 =A0 =A0 stop_stepping (ecs);
> =A0 =A0 =A0 =A0 =A0return;
> =A0 =A0 =A0 =A0}
> =A0 =A0 =A0 ecs->event_thread->stop_signal =3D TARGET_SIGNAL_TRAP;
> Index: src/gdb/linux-nat.c
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> --- src.orig/gdb/linux-nat.c =A0 =A02009-05-21 23:45:24.000000000 +0100
> +++ src/gdb/linux-nat.c 2009-05-24 17:09:03.000000000 +0100
> @@ -575,19 +575,17 @@ static int
> =A0linux_child_follow_fork (struct target_ops *ops, int follow_child)
> =A0{
> =A0 sigset_t prev_mask;
> - =A0ptid_t last_ptid;
> - =A0struct target_waitstatus last_status;
> =A0 int has_vforked;
> =A0 int parent_pid, child_pid;
>
> =A0 block_child_signals (&prev_mask);
>
> - =A0get_last_target_status (&last_ptid, &last_status);
> - =A0has_vforked =3D (last_status.kind =3D=3D TARGET_WAITKIND_VFORKED);
> - =A0parent_pid =3D ptid_get_lwp (last_ptid);
> + =A0has_vforked =3D (inferior_thread ()->pending_follow.kind
> + =A0 =A0 =A0 =A0 =A0 =A0 =A0 =A0=3D=3D TARGET_WAITKIND_VFORKED);
> + =A0parent_pid =3D ptid_get_lwp (inferior_ptid);
> =A0 if (parent_pid =3D=3D 0)
> - =A0 =A0parent_pid =3D ptid_get_pid (last_ptid);
> - =A0child_pid =3D PIDGET (last_status.value.related_pid);
> + =A0 =A0parent_pid =3D ptid_get_pid (inferior_ptid);
> + =A0child_pid =3D PIDGET (inferior_thread ()->pending_follow.value.relat=
ed_pid);
>
> =A0 if (! follow_child)
> =A0 =A0 {
> @@ -625,7 +623,7 @@ linux_child_follow_fork (struct target_o
> =A0 =A0 =A0 =A0 =A0/* Add process to GDB's tables. =A0*/
> =A0 =A0 =A0 =A0 =A0child_inf =3D add_inferior (child_pid);
>
> - =A0 =A0 =A0 =A0 parent_inf =3D find_inferior_pid (GET_PID (last_ptid));
> + =A0 =A0 =A0 =A0 parent_inf =3D current_inferior ();
> =A0 =A0 =A0 =A0 =A0child_inf->attach_flag =3D parent_inf->attach_flag;
> =A0 =A0 =A0 =A0 =A0copy_terminal_info (child_inf, parent_inf);
>
> @@ -692,21 +690,9 @@ linux_child_follow_fork (struct target_o
> =A0 =A0 }
> =A0 else
> =A0 =A0 {
> - =A0 =A0 =A0struct thread_info *last_tp =3D find_thread_pid (last_ptid);
> =A0 =A0 =A0 struct thread_info *tp;
> - =A0 =A0 =A0char child_pid_spelling[40];
> =A0 =A0 =A0 struct inferior *parent_inf, *child_inf;
>
> - =A0 =A0 =A0/* Copy user stepping state to the new inferior thread. =A0*/
> - =A0 =A0 =A0struct breakpoint *step_resume_breakpoint =3D last_tp->step_=
resume_breakpoint;
> - =A0 =A0 =A0CORE_ADDR step_range_start =3D last_tp->step_range_start;
> - =A0 =A0 =A0CORE_ADDR step_range_end =3D last_tp->step_range_end;
> - =A0 =A0 =A0struct frame_id step_frame_id =3D last_tp->step_frame_id;
> -
> - =A0 =A0 =A0/* Otherwise, deleting the parent would get rid of this
> - =A0 =A0 =A0 =A0breakpoint. =A0*/
> - =A0 =A0 =A0last_tp->step_resume_breakpoint =3D NULL;
> -
> =A0 =A0 =A0 /* Before detaching from the parent, remove all breakpoints f=
rom it. */
> =A0 =A0 =A0 remove_breakpoints ();
>
> @@ -723,7 +709,7 @@ linux_child_follow_fork (struct target_o
>
> =A0 =A0 =A0 child_inf =3D add_inferior (child_pid);
>
> - =A0 =A0 =A0parent_inf =3D find_inferior_pid (GET_PID (last_ptid));
> + =A0 =A0 =A0parent_inf =3D current_inferior ();
> =A0 =A0 =A0 child_inf->attach_flag =3D parent_inf->attach_flag;
> =A0 =A0 =A0 copy_terminal_info (child_inf, parent_inf);
>
> @@ -772,15 +758,6 @@ linux_child_follow_fork (struct target_o
>
> =A0 =A0 =A0 linux_nat_switch_fork (inferior_ptid);
> =A0 =A0 =A0 check_for_thread_db ();
> -
> - =A0 =A0 =A0tp =3D inferior_thread ();
> - =A0 =A0 =A0tp->step_resume_breakpoint =3D step_resume_breakpoint;
> - =A0 =A0 =A0tp->step_range_start =3D step_range_start;
> - =A0 =A0 =A0tp->step_range_end =3D step_range_end;
> - =A0 =A0 =A0tp->step_frame_id =3D step_frame_id;
> -
> - =A0 =A0 =A0/* Reset breakpoints in the child as appropriate. =A0*/
> - =A0 =A0 =A0follow_inferior_reset_breakpoints ();
> =A0 =A0 }
>
> =A0 restore_child_signals_mask (&prev_mask);
> Index: src/gdb/inf-ptrace.c
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> --- src.orig/gdb/inf-ptrace.c =A0 2009-05-21 23:45:24.000000000 +0100
> +++ src/gdb/inf-ptrace.c =A0 =A0 =A0 =A02009-05-24 18:20:14.000000000 +01=
00
> @@ -46,20 +46,8 @@ inf_ptrace_follow_fork (struct target_op
> =A0{
> =A0 pid_t pid, fpid;
> =A0 ptrace_state_t pe;
> - =A0struct thread_info *last_tp =3D NULL;
>
> - =A0/* FIXME: kettenis/20050720: This stuff should really be passed as
> - =A0 =A0 an argument by our caller. =A0*/
> - =A0{
> - =A0 =A0ptid_t ptid;
> - =A0 =A0struct target_waitstatus status;
> -
> - =A0 =A0get_last_target_status (&ptid, &status);
> - =A0 =A0gdb_assert (status.kind =3D=3D TARGET_WAITKIND_FORKED);
> -
> - =A0 =A0pid =3D ptid_get_pid (ptid);
> - =A0 =A0last_tp =3D find_thread_pid (ptid);
> - =A0}
> + =A0pid =3D ptid_get_pid (inferior_ptid);
>
> =A0 if (ptrace (PT_GET_PROCESS_STATE, pid,
> =A0 =A0 =A0 =A0 =A0 =A0 =A0 (PTRACE_TYPE_ARG3)&pe, sizeof pe) =3D=3D -1)
> @@ -70,18 +58,9 @@ inf_ptrace_follow_fork (struct target_op
>
> =A0 if (follow_child)
> =A0 =A0 {
> - =A0 =A0 =A0/* Copy user stepping state to the new inferior thread. =A0*/
> - =A0 =A0 =A0struct breakpoint *step_resume_breakpoint =3D last_tp->step_=
resume_breakpoint;
> - =A0 =A0 =A0CORE_ADDR step_range_start =3D last_tp->step_range_start;
> - =A0 =A0 =A0CORE_ADDR step_range_end =3D last_tp->step_range_end;
> - =A0 =A0 =A0struct frame_id step_frame_id =3D last_tp->step_frame_id;
> =A0 =A0 =A0 struct inferior *parent_inf, *child_inf;
> =A0 =A0 =A0 struct thread_info *tp;
>
> - =A0 =A0 =A0/* Otherwise, deleting the parent would get rid of this
> - =A0 =A0 =A0 =A0breakpoint. =A0*/
> - =A0 =A0 =A0last_tp->step_resume_breakpoint =3D NULL;
> -
> =A0 =A0 =A0 parent_inf =3D find_inferior_pid (pid);
>
> =A0 =A0 =A0 /* Add the child. =A0*/
> @@ -102,26 +81,15 @@ inf_ptrace_follow_fork (struct target_op
> =A0 =A0 =A0 /* Delete the parent. =A0*/
> =A0 =A0 =A0 detach_inferior (pid);
>
> - =A0 =A0 =A0tp =3D add_thread_silent (inferior_ptid);
> -
> - =A0 =A0 =A0tp->step_resume_breakpoint =3D step_resume_breakpoint;
> - =A0 =A0 =A0tp->step_range_start =3D step_range_start;
> - =A0 =A0 =A0tp->step_range_end =3D step_range_end;
> - =A0 =A0 =A0tp->step_frame_id =3D step_frame_id;
> -
> - =A0 =A0 =A0/* Reset breakpoints in the child as appropriate. =A0*/
> - =A0 =A0 =A0follow_inferior_reset_breakpoints ();
> + =A0 =A0 =A0add_thread_silent (inferior_ptid);
> =A0 =A0 }
> =A0 else
> =A0 =A0 {
> - =A0 =A0 =A0inferior_ptid =3D pid_to_ptid (pid);
> -
> =A0 =A0 =A0 /* Breakpoints have already been detached from the child by
> =A0 =A0 =A0 =A0 infrun.c. =A0*/
>
> =A0 =A0 =A0 if (ptrace (PT_DETACH, fpid, (PTRACE_TYPE_ARG3)1, 0) =3D=3D -=
1)
> =A0 =A0 =A0 =A0perror_with_name (("ptrace"));
> - =A0 =A0 =A0detach_inferior (pid);
> =A0 =A0 }
>
> =A0 return 0;
> Index: src/gdb/inf-ttrace.c
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> --- src.orig/gdb/inf-ttrace.c =A0 2009-05-21 23:45:24.000000000 +0100
> +++ src/gdb/inf-ttrace.c =A0 =A0 =A0 =A02009-05-24 17:09:03.000000000 +01=
00
> @@ -412,25 +412,13 @@ inf_ttrace_follow_fork (struct target_op
> =A0 pid_t pid, fpid;
> =A0 lwpid_t lwpid, flwpid;
> =A0 ttstate_t tts;
> - =A0struct thread_info *last_tp =3D NULL;
> - =A0struct breakpoint *step_resume_breakpoint =3D NULL;
> - =A0CORE_ADDR step_range_start =3D 0, step_range_end =3D 0;
> - =A0struct frame_id step_frame_id =3D null_frame_id;
> -
> - =A0/* FIXME: kettenis/20050720: This stuff should really be passed as
> - =A0 =A0 an argument by our caller. =A0*/
> - =A0{
> - =A0 =A0ptid_t ptid;
> - =A0 =A0struct target_waitstatus status;
> -
> - =A0 =A0get_last_target_status (&ptid, &status);
> - =A0 =A0gdb_assert (status.kind =3D=3D TARGET_WAITKIND_FORKED
> - =A0 =A0 =A0 =A0 =A0 =A0 =A0 || status.kind =3D=3D TARGET_WAITKIND_VFORK=
ED);
> -
> - =A0 =A0pid =3D ptid_get_pid (ptid);
> - =A0 =A0lwpid =3D ptid_get_lwp (ptid);
> - =A0 =A0last_tp =3D find_thread_pid (ptid);
> - =A0}
> + =A0struct thread_info *tp =3D inferior_thread ();
> +
> + =A0gdb_assert (tp->pending_follow.kind =3D=3D TARGET_WAITKIND_FORKED
> + =A0 =A0 =A0 =A0 =A0 =A0 || tp->pending_follow.kind =3D=3D TARGET_WAITKI=
ND_VFORKED);
> +
> + =A0pid =3D ptid_get_pid (inferior_ptid);
> + =A0lwpid =3D ptid_get_lwp (inferior_ptid);
>
> =A0 /* Get all important details that core GDB doesn't (and shouldn't)
> =A0 =A0 =A0know about. =A0*/
> @@ -462,16 +450,6 @@ inf_ttrace_follow_fork (struct target_op
>
> =A0 =A0 =A0 parent_inf =3D find_inferior_pid (pid);
>
> - =A0 =A0 =A0/* Copy user stepping state to the new inferior thread. =A0*/
> - =A0 =A0 =A0step_resume_breakpoint =3D last_tp->step_resume_breakpoint;
> - =A0 =A0 =A0step_range_start =3D last_tp->step_range_start;
> - =A0 =A0 =A0step_range_end =3D last_tp->step_range_end;
> - =A0 =A0 =A0step_frame_id =3D last_tp->step_frame_id;
> -
> - =A0 =A0 =A0/* Otherwise, deleting the parent would get rid of this
> - =A0 =A0 =A0 =A0breakpoint. =A0*/
> - =A0 =A0 =A0last_tp->step_resume_breakpoint =3D NULL;
> -
> =A0 =A0 =A0 inferior_ptid =3D ptid_build (fpid, flwpid, 0);
> =A0 =A0 =A0 inf =3D add_inferior (fpid);
> =A0 =A0 =A0 inf->attach_flag =3D parent_inf->attach_flag;
> @@ -553,14 +531,6 @@ Detaching after fork from child process
> =A0 =A0 =A0 =A0xmalloc (sizeof (struct inf_ttrace_private_thread_info));
> =A0 =A0 =A0 memset (ti->private, 0,
> =A0 =A0 =A0 =A0 =A0 =A0 =A0sizeof (struct inf_ttrace_private_thread_info)=
);
> -
> - =A0 =A0 =A0ti->step_resume_breakpoint =3D step_resume_breakpoint;
> - =A0 =A0 =A0ti->step_range_start =3D step_range_start;
> - =A0 =A0 =A0ti->step_range_end =3D step_range_end;
> - =A0 =A0 =A0ti->step_frame_id =3D step_frame_id;
> -
> - =A0 =A0 =A0/* Reset breakpoints in the child as appropriate. =A0*/
> - =A0 =A0 =A0follow_inferior_reset_breakpoints ();
> =A0 =A0 }
>
> =A0 return 0;
> Index: src/gdb/testsuite/gdb.threads/fork-thread-pending.c
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> --- /dev/null =A0 1970-01-01 00:00:00.000000000 +0000
> +++ src/gdb/testsuite/gdb.threads/fork-thread-pending.c 2009-05-24 17:09:=
03.000000000 +0100
> @@ -0,0 +1,109 @@
> +/* This testcase is part of GDB, the GNU debugger.
> +
> + =A0 Copyright 2008, 2009 Free Software Foundation, Inc.
> +
> + =A0 This program is free software; you can redistribute it and/or modify
> + =A0 it under the terms of the GNU General Public License as published by
> + =A0 the Free Software Foundation; either version 3 of the License, or
> + =A0 (at your option) any later version.
> +
> + =A0 This program is distributed in the hope that it will be useful,
> + =A0 but WITHOUT ANY WARRANTY; without even the implied warranty of
> + =A0 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. =A0See the
> + =A0 GNU General Public License for more details.
> +
> + =A0 You should have received a copy of the GNU General Public License
> + =A0 along with this program. =A0If not, see <http://www.gnu.org/license=
s/>. =A0*/
> +
> +#include <pthread.h>
> +#include <assert.h>
> +#include <unistd.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <errno.h>
> +#include <unistd.h>
> +#include <sys/types.h>
> +#include <sys/wait.h>
> +
> +#define NUMTHREADS 10
> +
> +volatile int done =3D 0;
> +
> +static void *
> +start (void *arg)
> +{
> + =A0while (!done)
> + =A0 =A0usleep (100);
> + =A0assert (0);
> + =A0return arg;
> +}
> +
> +void *
> +thread_function (void *arg)
> +{
> + =A0int x =3D * (int *) arg;
> +
> + =A0printf ("Thread <%d> executing\n", x);
> +
> + =A0while (!done)
> + =A0 =A0usleep (100);
> +
> + =A0return NULL;
> +}
> +
> +void *
> +thread_forker (void *arg)
> +{
> + =A0int x =3D * (int *) arg;
> + =A0pid_t pid;
> + =A0int rv;
> + =A0int i;
> + =A0pthread_t thread;
> +
> + =A0printf ("Thread forker <%d> executing\n", x);
> +
> + =A0switch ((pid =3D fork ()))
> + =A0 =A0{
> + =A0 =A0case -1:
> + =A0 =A0 =A0assert (0);
> + =A0 =A0default:
> + =A0 =A0 =A0wait (&rv);
> + =A0 =A0 =A0done =3D 1;
> + =A0 =A0 =A0break;
> + =A0 =A0case 0:
> + =A0 =A0 =A0i =3D pthread_create (&thread, NULL, start, NULL);
> + =A0 =A0 =A0assert (i =3D=3D 0);
> + =A0 =A0 =A0i =3D pthread_join (thread, NULL);
> + =A0 =A0 =A0assert (i =3D=3D 0);
> +
> + =A0 =A0 =A0assert (0);
> + =A0 =A0}
> +
> + =A0return NULL;
> +}
> +
> +int
> +main (void)
> +{
> + =A0pthread_t threads[NUMTHREADS];
> + =A0int args[NUMTHREADS];
> + =A0int i, j;
> +
> + =A0/* Create a few threads that do mostly nothing, and then one that
> + =A0 =A0 forks. =A0*/
> + =A0for (j =3D 0; j < NUMTHREADS - 1; ++j)
> + =A0 =A0{
> + =A0 =A0 =A0args[j] =3D j;
> + =A0 =A0 =A0pthread_create (&threads[j], NULL, thread_function, &args[j]=
);
> + =A0 =A0}
> +
> + =A0args[j] =3D j;
> + =A0pthread_create (&threads[j], NULL, thread_forker, &args[j]);
> +
> + =A0for (j =3D 0; j < NUMTHREADS; ++j)
> + =A0 =A0{
> + =A0 =A0 =A0pthread_join (threads[j], NULL);
> + =A0 =A0}
> +
> + =A0return 0;
> +}
> Index: src/gdb/testsuite/gdb.threads/fork-thread-pending.exp
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
> --- /dev/null =A0 1970-01-01 00:00:00.000000000 +0000
> +++ src/gdb/testsuite/gdb.threads/fork-thread-pending.exp =A0 =A0 =A0 200=
9-05-24 17:29:19.000000000 +0100
> @@ -0,0 +1,128 @@
> +# Copyright (C) 2009 Free Software Foundation, Inc.
> +
> +# This program is free software; you can redistribute it and/or modify
> +# it under the terms of the GNU General Public License as published by
> +# the Free Software Foundation; either version 3 of the License, or
> +# (at your option) any later version.
> +#
> +# This program is distributed in the hope that it will be useful,
> +# but WITHOUT ANY WARRANTY; without even the implied warranty of
> +# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. =A0See the
> +# GNU General Public License for more details.
> +#
> +# You should have received a copy of the GNU General Public License
> +# along with this program. =A0If not, see <http://www.gnu.org/licenses/>.
> +
> +# There's no support for `set follow-fork-mode' in the remote
> +# protocol.
> +if { [is_remote target] } {
> + =A0 =A0return 0
> +}
> +
> +# Only GNU/Linux is known to support `set follow-fork-mode child'.
> +#
> +if { ! [istarget "*-*-linux*"] } {
> + =A0 =A0return 0
> +}
> +
> +set testfile fork-thread-pending
> +set srcfile ${testfile}.c
> +set binfile ${objdir}/${subdir}/${testfile}
> +
> +if {[gdb_compile_pthreads "${srcdir}/${subdir}/${srcfile}" "${binfile}" =
executable {debug}] !=3D "" } {
> + =A0 =A0return -1
> +}
> +
> +gdb_exit
> +gdb_start
> +gdb_reinitialize_dir $srcdir/$subdir
> +
> +gdb_load ${binfile}
> +if ![runto_main] then {
> + =A0 fail "Can't run to main"
> + =A0 return 0
> +}
> +
> +gdb_test "set follow-fork-mode child" "" "1, set follow-fork-mode child"
> +gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" "1, insert fork c=
atchpoint"
> +gdb_breakpoint "start" "" "1, set breakpoint at start"
> +
> +gdb_test "continue" "Catchpoint.*" "1, get to the fork event"
> +
> +gdb_test "info threads" " Thread .* Thread .* Thread .* Thread .*" "1, m=
ultiple threads found"
> +
> +gdb_test "thread 2" "" "1, switched away from event thread"
> +
> +gdb_test "continue" "Not resuming.*" "1, refused to resume"
> +
> +set test "1, followed to the child, found one thread"
> +gdb_test_multiple "info threads" "metest" {
> + =A0 =A0-re " Thread .* Thread .*$gdb_prompt $" {
> + =A0 =A0 =A0 fail "$test"
> + =A0 =A0}
> + =A0 =A0-re " Thread .*$gdb_prompt $" {
> + =A0 =A0 =A0 pass "$test"
> + =A0 =A0}
> + =A0 =A0-re "$gdb_prompt $" {
> + =A0 =A0 =A0 fail "$test (unknown output)"
> + =A0 =A0}
> + =A0 =A0timeout {
> + =A0 =A0 =A0 fail "$test (timeout)"
> + =A0 =A0}
> +}
> +
> +gdb_test "continue" "Breakpoint 3, start.*" "1, get to the spawned threa=
d in fork child"
> +
> +set test "1, followed to the child, found two threads"
> +gdb_test_multiple "info threads" "$test" {
> + =A0 =A0-re " Thread .* Thread .* Thread .*$gdb_prompt $" {
> + =A0 =A0 =A0 fail "$test"
> + =A0 =A0}
> + =A0 =A0-re " Thread .* Thread .*$gdb_prompt $" {
> + =A0 =A0 =A0 pass "$test"
> + =A0 =A0}
> + =A0 =A0-re "$gdb_prompt $" {
> + =A0 =A0 =A0 fail "$test (unknown output)"
> + =A0 =A0}
> + =A0 =A0timeout {
> + =A0 =A0 =A0 fail "$test (timeout)"
> + =A0 =A0}
> +}
> +
> +# Start over, but this time, don't switch away from the fork event threa=
d.
> +
> +gdb_exit
> +gdb_start
> +gdb_reinitialize_dir $srcdir/$subdir
> +
> +gdb_load ${binfile}
> +if ![runto_main] then {
> + =A0 fail "Can't run to main"
> + =A0 return 0
> +}
> +
> +gdb_test "set follow-fork-mode child" "" "2, set follow-fork-mode child"
> +gdb_test "catch fork" "Catchpoint \[0-9\]* \\(fork\\)" "2, insert fork c=
atchpoint"
> +gdb_breakpoint "start"
> +
> +gdb_test "continue" "Catchpoint.*" "2, get to the fork event"
> +
> +gdb_test "info threads" " Thread .* Thread .* Thread .* Thread .*" "2, m=
ultiple threads found"
> +
> +gdb_test "continue" "Breakpoint 3, start.*" "2, get to the spawned threa=
d in fork child"
> +
> +set test "2, followed to the child, found two threads"
> +gdb_test_multiple "info threads" "$test" {
> + =A0 =A0-re " Thread .* Thread .* Thread .*$gdb_prompt $" {
> + =A0 =A0 =A0 fail "$test"
> + =A0 =A0}
> + =A0 =A0-re " Thread .* Thread .*$gdb_prompt $" {
> + =A0 =A0 =A0 pass "$test"
> + =A0 =A0}
> + =A0 =A0-re "$gdb_prompt $" {
> + =A0 =A0 =A0 fail "$test (unknown output)"
> + =A0 =A0}
> + =A0 =A0timeout {
> + =A0 =A0 =A0 fail "$test (timeout)"
> + =A0 =A0}
> +}
>

fyi, I just did an update and am getting a build failure (i686-linux).

gcc -m32 -g -O2   -I. -I../../../src/gdb -I../../../src/gdb/common
-I../../../src/gdb/config -DLOCALEDIR=3D"\"/usr/share/locale\""
-DHAVE_CONFIG_H -I../../../src/\
gdb/../include/opcode -I../../../src/gdb/../readline/.. -I../bfd
-I../../../src/gdb/../bfd -I../../../src/gdb/../include
-I../libdecnumber -I../../../src/gdb/..\
/libdecnumber  -I../../../src/gdb/gnulib -Ignulib  -DMI_OUT=3D1 -DTUI=3D1
-Wall -Wdeclaration-after-statement -Wpointer-arith
-Wformat-nonliteral -Wno-pointer-sign\
 -Wno-unused -Wno-switch -Wno-char-subscripts -Werror -c -o infrun.o
-MT infrun.o -MMD -MP -MF .deps/infrun.Tpo ../../../src/gdb/infrun.c
cc1: warnings being treated as errors
../../../src/gdb/infrun.c: In function =91follow_fork=92:
../../../src/gdb/infrun.c:298: warning: =91step_frame_id.special_addr_p=92
may be used uninitialized in this function
../../../src/gdb/infrun.c:298: warning: =91step_frame_id.code_addr_p=92
may be used uninitialized in this function
../../../src/gdb/infrun.c:298: warning: =91step_frame_id.stack_addr_p=92
may be used uninitialized in this function
../../../src/gdb/infrun.c:298: warning: =91step_frame_id.special_addr=92
may be used uninitialized in this function
../../../src/gdb/infrun.c:298: warning: =91step_frame_id.code_addr=92 may
be used uninitialized in this function
../../../src/gdb/infrun.c:298: warning: =91step_frame_id.stack_addr=92 may
be used uninitialized in this function
../../../src/gdb/infrun.c:297: warning: =91step_range_end=92 may be used
uninitialized in this function
../../../src/gdb/infrun.c:296: warning: =91step_range_start=92 may be used
uninitialized in this function
../../../src/gdb/infrun.c:295: warning: =91step_resume_breakpoint=92 may
be used uninitialized in this function
make: *** [infrun.o] Error 1

gcc's not smart enough to detect it's actually ok.

2009-05-24  Doug Evans  <dje@google.com>

        * infrun.c (follow_fork): Initialize new step_* locals
        to avoid "may be used uninitialized" warnings.

Index: infrun.c
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D
RCS file: /cvs/src/src/gdb/infrun.c,v
retrieving revision 1.377
diff -u -p -r1.377 infrun.c
--- infrun.c    24 May 2009 18:00:08 -0000      1.377
+++ infrun.c    24 May 2009 20:26:28 -0000
@@ -290,12 +290,12 @@ follow_fork (void)

   /* Copy user stepping state to the new inferior thread.  FIXME: the
      followed fork child thread should have a copy of most of the
-     parent thread structure's run control related fields, not just
-     these.  */
-  struct breakpoint *step_resume_breakpoint;
-  CORE_ADDR step_range_start;
-  CORE_ADDR step_range_end;
-  struct frame_id step_frame_id;
+     parent thread structure's run control related fields, not just these.
+     Initialized to avoid "may be used uninitialized" warnings from gcc.  =
*/
+  struct breakpoint *step_resume_breakpoint =3D NULL;
+  CORE_ADDR step_range_start =3D 0;
+  CORE_ADDR step_range_end =3D 0;
+  struct frame_id step_frame_id =3D { 0 };

   if (!non_stop)
     {