Because the actual construction of a breakpoint is buried deep in
create_breakpoint, at present it's necessary to have a new bp_
enumerator constant any time a new subclass is needed. Static marker
tracepoints are one such case, so this patch introduces
bp_static_marker_tracepoint and updates various spots to recognize it.
This converts "ordinary" breakpoint to use vtable_breakpoint_ops.
Recall that an ordinary breakpoint is both the kind normally created
by users, and also a base class used by other classes.
This adds a few new subclasses of breakpoint. The inheritance
hierarchy is chosen to reflect what's already present in
initialize_breakpoint_ops -- it mirrors the way that the _ops
structures are filled in.
This patch also changes new_breakpoint_from_type to create the correct
sublcass based on bptype. This is important due to the somewhat
inverted way in which create_breakpoint works; and in particular later
patches will change some of these entries.
This converts watchpoints and masked watchpoints. to use
vtable_breakpoint_ops. For masked watchpoints, a new subclass must be
introduced, and watch_command_1 is changed to create one.
This adds methods to struct breakpoint. Each method has a similar
signature to a corresponding function in breakpoint_ops, with the
exceptions of create_sals_from_location and create_breakpoints_sal,
which can't be virtual methods on breakpoint -- they are only used
during the construction of breakpoints.
Then, this adds a new vtable_breakpoint_ops structure and populates it
with functions that simply forward a call from breakpoint_ops to the
corresponding virtual method. These are all done with lambdas,
because they are just a stepping stone -- by the end of the series,
this structure will be deleted.
This changes breakpoint_ops::print_one to return bool, and updates all
the implementations and the caller. The caller is changed so that a
NULL check is no longer needed -- something that will be impossible
with a real method.
The "catch load" code is reasonably self-contained, and so this patch
moves it out of breakpoint.c and into a new file, break-catch-load.c.
One function from breakpoint.c, print_solib_event, now has to be
exposed, but this seems pretty reasonable.
If GDB reports a watchpoint hit, and then the next event is not
TARGET_WAITKIND_STOPPED, but instead some event for which there's a
catchpoint, such that GDB calls bpstat_stop_status, GDB mistakenly
thinks the watchpoint triggered. Vis, using foll-fork.c:
(gdb) awatch v
Hardware access (read/write) watchpoint 2: v
(gdb) catch fork
Catchpoint 3 (fork)
(gdb) c
Continuing.
Hardware access (read/write) watchpoint 2: v
Old value = 0
New value = 5
main () at gdb.base/foll-fork.c:16
16 pid = fork ();
(gdb)
Continuing.
Hardware access (read/write) watchpoint 2: v <<<<
<<<< these lines are spurious
Value = 5 <<<<
Catchpoint 3 (forked process 1712369), arch_fork (ctid=0x7ffff7fa4810) at arch-fork.h:49
49 arch-fork.h: No such file or directory.
(gdb)
The problem is that when we handle the fork event, nothing called
watchpoints_triggered before calling bpstat_stop_status. Thus, each
watchpoint's watchpoint_triggered field was still set to
watch_triggered_yes from the previous (real) watchpoint stop.
watchpoint_triggered is only current called in the handle_signal_stop
path, when handling TARGET_WAITKIND_STOPPED.
This fixes it by adding watchpoint_triggered calls in the other events
paths that call bpstat_stop_status. But instead of adding them
explicitly, it adds a new function bpstat_stop_status_nowatch that
wraps bpstat_stop_status and calls watchpoint_triggered, and then
replaces most calls to bpstat_stop_status with calls to
bpstat_stop_status_nowatch.
This required constifying watchpoints_triggered.
New test included, which fails without the fix.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28621
Change-Id: I282b38c2eee428d25319af3bc842f9feafed461c
This commit brings all the changes made by running gdb/copyright.py
as per GDB's Start of New Year Procedure.
For the avoidance of doubt, all changes in this commits were
performed by the script.
While working on target_waitstatus changes, I noticed a few places where
const target_waitstatus objects could be passed by reference instead of
by pointers. And in some cases, places where a target_waitstatus could
be passed as const, but was not. Convert them as much as possible.
Change-Id: Ied552d464be5d5b87489913b95f9720a5ad50c5a
I don't find that the bpstat typedef, which hides a pointer, is
particularly useful. In fact, it confused me many times, and I just see
it as something to remember that adds cognitive load. Also, with C++,
we might want to be able to pass bpstats objects by const-reference, not
necessarily by pointer.
So, remove the bpstat typedef and rename struct bpstats to bpstat (since
it represents one bpstat, it makes sense that it is singular).
Change-Id: I52e763b6e54ee666a9e045785f686d37b4f5f849
Remove breakpoint_find_if, replace its sole usage with using
all_breakpoints directly instead. At the same time, change return
types to use bool.
Change-Id: I9ec392236b4804b362d16ab563330b9c07311106
I don't understand what the sfunc function type in
cmd_list_element::function is for. Compared to cmd_simple_func_ftype,
it has an extra cmd_list_element parameter, giving the callback access
to the cmd_list_element for the command being invoked. This allows
registering the same callback with many commands, and alter the behavior
using the cmd_list_element's context.
From the comment in cmd_list_element, it sounds like at some point it
was the callback function type for set and show functions, hence the
"s". But nowadays, it's used for many more commands that need to access
the cmd_list_element object (see add_catch_command for example).
I don't really see the point of having sfunc at all, since do_sfunc is
just a trivial shim that changes the order of the arguments. All
commands using sfunc could just as well set cmd_list_element::func to
their callback directly.
Therefore, remove the sfunc field in cmd_list_element and everything
that goes with it. Rename cmd_const_sfunc_ftype to cmd_func_ftype and
use it for cmd_list_element::func, as well as for the add_setshow
commands.
Change-Id: I1eb96326c9b511c293c76996cea0ebc51c70fac0
I was always a bit confused by next_adapter, because it kind of mixes
the element type and the iterator type. In reality, it is not much more
than a class that wraps two iterators (begin and end). However, it
assumes that:
- you can construct the begin iterator by passing a pointer to the
first element of the iterable
- you can default-construct iterator to make the end iterator
I think that by generalizing it a little bit, we can re-use it at more
places.
Rename it to "iterator_range". I think it describes a bit better: it's
a range made by wrapping a begin and end iterator. Move it to its own
file, since it's not related to next_iterator anymore.
iterator_range has two constructors. The variadic one, where arguments
are forwarded to construct the underlying begin iterator. The end
iterator is constructed through default construction. This is a
generalization of what we have today.
There is another constructor which receives already constructed begin
and end iterators, useful if the end iterator can't be obtained by
default-construction. Or, if you wanted to make a range that does not
end at the end of the container, you could pass any iterator as the
"end".
This generalization allows removing some "range" classes, like
all_inferiors_range. These classes existed only to pass some arguments
when constructing the begin iterator. With iterator_range, those same
arguments are passed to the iterator_range constructed and then
forwarded to the constructed begin iterator.
There is a small functional difference in how iterator_range works
compared to next_adapter. next_adapter stored the pointer it received
as argument and constructeur an iterator in the `begin` method.
iterator_range constructs the begin iterator and stores it as a member.
Its `begin` method returns a copy of that iterator.
With just iterator_range, uses of next_adapter<foo> would be replaced
with:
using foo_iterator = next_iterator<foo>;
using foo_range = iterator_range<foo_iterator>;
However, I added a `next_range` wrapper as a direct replacement for
next_adapter<foo>. IMO, next_range is a slightly better name than
next_adapter.
The rest of the changes are applications of this new class.
gdbsupport/ChangeLog:
* next-iterator.h (class next_adapter): Remove.
* iterator-range.h: New.
gdb/ChangeLog:
* breakpoint.h (bp_locations_range): Remove.
(bp_location_range): New.
(struct breakpoint) <locations>: Adjust type.
(breakpoint_range): Use iterator_range.
(tracepoint_range): Use iterator_range.
* breakpoint.c (breakpoint::locations): Adjust return type.
* gdb_bfd.h (gdb_bfd_section_range): Use iterator_range.
* gdbthread.h (all_threads_safe): Pass argument to
all_threads_safe_range.
* inferior-iter.h (all_inferiors_range): Use iterator_range.
(all_inferiors_safe_range): Use iterator_range.
(all_non_exited_inferiors_range): Use iterator_range.
* inferior.h (all_inferiors, all_non_exited_inferiors): Pass
inferior_list as argument.
* objfiles.h (struct objfile) <compunits_range>: Remove.
<compunits>: Return compunit_symtab_range.
* progspace.h (unwrapping_objfile_iterator)
<unwrapping_objfile_iterator>: Take parameter by value.
(unwrapping_objfile_range): Use iterator_range.
(struct program_space) <objfiles_range>: Define with "using".
<objfiles>: Adjust.
<objfiles_safe_range>: Define with "using".
<objfiles_safe>: Adjust.
<solibs>: Return so_list_range, define here.
* progspace.c (program_space::solibs): Remove.
* psymtab.h (class psymtab_storage) <partial_symtab_iterator>:
New.
<partial_symtab_range>: Use iterator_range.
* solist.h (so_list_range): New.
* symtab.h (compunit_symtab_range):
New.
(symtab_range): New.
(compunit_filetabs): Change to a function.
* thread-iter.h (inf_threads_range,
inf_non_exited_threads_range, safe_inf_threads_range,
all_threads_safe_range): Use iterator_range.
* top.h (ui_range): New.
(all_uis): Use ui_range.
Change-Id: Ib7a9d2a3547f45f01aa1c6b24536ba159db9b854
Remove it, change users (well, a single one) to use all_bp_locations.
This requires moving all_bp_locations to breakpoint.h to expose it.
gdb/ChangeLog:
* breakpoint.h (iterate_over_bp_locations): Remove. Update
users to use all_bp_locations.
(all_bp_locations): New.
* breakpoint.c (all_bp_locations): Make non-static.
(iterate_over_bp_locations): Remove.
Change-Id: Iaf1f716d6c2c5b2975579b3dc113a86f5d0975be
Now that we have range functions that let us use ranged for loops, we
can remove iterate_over_breakpoints in favor of those, which are easier
to read and write. This requires exposing the declaration of
all_breakpoints and all_breakpoints_safe in breakpoint.h, as well as the
supporting types.
Change some users of iterate_over_breakpoints to use all_breakpoints,
when they don't need to delete the breakpoint, and all_breakpoints_safe
otherwise.
gdb/ChangeLog:
* breakpoint.h (iterate_over_breakpoints): Remove. Update
callers to use all_breakpoints or all_breakpoints_safe.
(breakpoint_range, all_breakpoints, breakpoint_safe_range,
all_breakpoints_safe): Move here.
* breakpoint.c (all_breakpoints, all_breakpoints_safe): Make
non-static.
(iterate_over_breakpoints): Remove.
* python/py-finishbreakpoint.c (bpfinishpy_detect_out_scope_cb):
Return void.
* python/py-breakpoint.c (build_bp_list): Add comment, reverse
return value logic.
* guile/scm-breakpoint.c (bpscm_build_bp_list): Return void.
Change-Id: Idde764a1f577de0423e4f2444a7d5cdb01ba5e48
Add the breakpoint::locations method, which returns a range that can be
used to iterate over a breakpoint's locations. This shortens
for (bp_location *loc = b->loc; loc != nullptr; loc = loc->next)
into
for (bp_location *loc : b->locations ())
Change all the places that I found that could use it.
gdb/ChangeLog:
* breakpoint.h (bp_locations_range): New.
(struct breakpoint) <locations>: New. Use where possible.
Change-Id: I1ba2f7d93d57e544e1f8609124587dcf2e1da037
Same idea as the previous patches, but to replace the ALL_TRACEPOINTS
macro. Define a new filtered_iterator that only keeps the breakpoints
for which is_tracepoint returns true (just like the macro did).
I would have like to make it so tracepoint_range yields some
`tracepoint *` instead of some `breakpoint *`, that would help simplify
the callers, who wouldn't have to do the cast themselves. But I didn't
find an obvious way to do it. It can always be added later.
It turns out there is already an all_tracepoints function, which returns
a vector containing all the breakpoints that are tracepoint. Remove it,
most users will just work seamlessly with the new function. The
exception is start_tracing, which iterated multiple times on the vector.
Adapt this one so it iterates multiple times on the returned range.
Since the existing users of all_tracepoints are outside of breakpoint.c,
this requires defining all_tracepoints and a few supporting types in
breakpoint.h. So, move breakpoint_iterator from breakpoint.c to
breakpoint.h.
gdb/ChangeLog:
* breakpoint.h (all_tracepoints): Remove.
(breakpoint_iterator): Move here.
(struct tracepoint_filter): New.
(tracepoint_iterator): New.
(tracepoint_range): New.
(all_tracepoints): New.
* breakpoint.c (ALL_TRACEPOINTS): Remove, replace all users with
all_tracepoints.
(breakpoint_iterator): Move to header.
(all_tracepoints): New.
* tracepoint.c (start_tracing): Adjust.
Change-Id: I76b1bba4215dbec7a03846c568368aeef7f1e05a
Add a '--force' flag to the '-break-condition' command to be
able to force conditions.
gdb/ChangeLog:
2021-05-06 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* mi/mi-cmd-break.c (mi_cmd_break_condition): New function.
* mi/mi-cmds.c: Change the binding of "-break-condition" to
mi_cmd_break_condition.
* mi/mi-cmds.h (mi_cmd_break_condition): Declare.
* breakpoint.h (set_breakpoint_condition): Declare a new
overload.
* breakpoint.c (set_breakpoint_condition): New overloaded function
extracted out from ...
(condition_command): ... this.
* NEWS: Mention the change.
gdb/testsuite/ChangeLog:
2021-05-06 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* gdb.mi/mi-break.exp (test_forced_conditions): Add a test
for the -break-condition command's "--force" flag.
gdb/doc/ChangeLog:
2021-05-06 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* gdb.texinfo (GDB/MI Breakpoint Commands): Mention the
'--force' flag of the '-break-condition' command.
Use a function_view instead of function pointer + data. Actually,
nothing uses the data anyway, but that makes iterate_over_bp_locations
more like iterate_over_breakpoints.
gdb/ChangeLog:
* breakpoint.c (iterate_over_bp_locations): Change callback to
function view, remove data parameter.
* breakpoint.h (iterate_over_bp_locations): Likewise.
* record-full.c (record_full_sync_record_breakpoints): Remove
data parameter.
Change-Id: I66cdc94a505f67bc640bcc66865fb535ee939a57
The 'create_breakpoint' function takes a 'parse_extra' argument that
determines whether the condition, thread, and force-condition
specifiers should be parsed from the extra string or be used from the
function arguments. However, for the case when 'parse_extra' is
false, there is no way to pass the force-condition specifier. This
patch adds it as a new argument.
Also, in the case when parse_extra is false, the current behavior is
as if the condition is being forced. This is a bug. The default
behavior should reject the breakpoint. See below for a demo of this
incorrect behavior. (The MI command '-break-insert' uses the
'create_breakpoint' function with parse_extra=0.)
$ gdb -q --interpreter=mi3 /tmp/simple
=thread-group-added,id="i1"
=cmd-param-changed,param="history save",value="on"
=cmd-param-changed,param="auto-load safe-path",value="/"
~"Reading symbols from /tmp/simple...\n"
(gdb)
-break-insert -c junk -f main
&"warning: failed to validate condition at location 1, disabling:\n "
&"No symbol \"junk\" in current context.\n"
^done,bkpt={number="1",type="breakpoint",disp="keep",enabled="y",addr="<MULTIPLE>",cond="junk",times="0",original-location="main",locations=[{number="1.1",enabled="N",addr="0x000000000000114e",func="main",file="/tmp/simple.c",fullname="/tmp/simple.c",line="2",thread-groups=["i1"]}]}
(gdb)
break main if junk
&"break main if junk\n"
&"No symbol \"junk\" in current context.\n"
^error,msg="No symbol \"junk\" in current context."
(gdb)
break main -force-condition if junk
&"break main -force-condition if junk\n"
~"Note: breakpoint 1 also set at pc 0x114e.\n"
&"warning: failed to validate condition at location 1, disabling:\n "
&"No symbol \"junk\" in current context.\n"
~"Breakpoint 2 at 0x114e: file /tmp/simple.c, line 2.\n"
=breakpoint-created,bkpt={number="2",type="breakpoint",disp="keep",enabled="y",addr="<MULTIPLE>",cond="junk",times="0",original-location="main",locations=[{number="2.1",enabled="N",addr="0x000000000000114e",func="main",file="/tmp/simple.c",fullname="/tmp/simple.c",line="2",thread-groups=["i1"]}]}
^done
(gdb)
After applying this patch, we get the behavior below:
(gdb)
-break-insert -c junk -f main
^error,msg="No symbol \"junk\" in current context."
This restores the behavior that is present in the existing releases.
gdb/ChangeLog:
2021-04-21 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* breakpoint.h (create_breakpoint): Add a new parameter,
'force_condition'.
* breakpoint.c (create_breakpoint): Use the 'force_condition'
argument when 'parse_extra' is false to check if the condition
is invalid at all of the breakpoint locations.
Update the users below.
(break_command_1)
(dprintf_command)
(trace_command)
(ftrace_command)
(strace_command)
(create_tracepoint_from_upload): Update.
* guile/scm-breakpoint.c (gdbscm_register_breakpoint_x): Update.
* mi/mi-cmd-break.c (mi_cmd_break_insert_1): Update.
* python/py-breakpoint.c (bppy_init): Update.
* python/py-finishbreakpoint.c (bpfinishpy_init): Update.
gdb/testsuite/ChangeLog:
2021-04-21 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* gdb.mi/mi-break.exp: Extend with checks for invalid breakpoint
conditions.
This commits the result of running gdb/copyright.py as per our Start
of New Year procedure...
gdb/ChangeLog
Update copyright year range in copyright header of all GDB files.
This changes bp_location to derive from refcounted_object, introduces
a ref_ptr specialization for this type, and then changes
bpstats::bp_location_at to use that specialization. This removes some
manual reference counting and simplifies the code.
gdb/ChangeLog
2020-12-11 Tom Tromey <tom@tromey.com>
* inline-frame.c (stopped_by_user_bp_inline_frame): Update.
* ada-lang.c (check_status_exception): Update.
* breakpoint.c (free_bp_location): Remove.
(decref_bp_location): Use bp_location_ref_policy.
(bpstats::bpstats): Don't call incref_bp_location.
(bpstats::~bpstats): Remove.
(bpstats::bpstats): Update.
(bpstat_check_watchpoint, bpstat_check_breakpoint_conditions)
(bp_location::bp_location): Update.
(incref_bp_location): Remove.
(bkpt_print_it): Update.
* breakpoint.h (class bp_location): Derive from
refcounted_object.
(struct bpstats): Remove destructor.
<bp_location_at>: Now a bp_location_ref_ptr.
<refc>: Remove.
(bp_location_ref_ptr): New typedef.
(struct bp_location_ref_policy): New.
A little int to bool conversion around the 'watch' type commands.
There should be no user visible changes after this commit.
gdb/ChangeLog:
* breakpoint.c (update_watchpoint): Pass 'false' not '0'.
(watch_command_1): Update parameter types. Convert locals to
bool.
(watch_command_wrapper): Change parameter type.
(watch_maybe_just_location): Change locals to bool.
(rwatch_command_wrapper): Update parameter type.
(awatch_command_wrapper): Update parameter type.
* breakpoint.h (watch_command_wrapper): Change parameter type.
(rwatch_command_wrapper): Update parameter type.
(awatch_command_wrapper): Update parameter type.
* eval.c (fetch_subexp_value): Change parameter type.
* ppc-linux-nat.c (ppc_linux_nat_target::check_condition): Pass
'false' not '0'.
* value.h (fetch_subexp_value): Change parameter type in
declaration.
The previous patch made it possible to define a condition if it's
valid at some locations. If the condition is invalid at all of the
locations, it's rejected. However, there may be cases where the user
knows the condition *will* be valid at a location in the future,
e.g. due to a shared library load.
To make it possible that such condition can be defined, this patch
adds an optional '-force' flag to the 'condition' command, and,
respectively, a '-force-condition' flag to the 'break'command. When
the force flag is passed, the condition is not rejected even when it
is invalid for all the current locations (note that all the locations
would be internally disabled in this case).
For instance:
(gdb) break test.c:5
Breakpoint 1 at 0x1155: file test.c, line 5.
(gdb) cond 1 foo == 42
No symbol "foo" in current context.
Defining the condition was not possible because 'foo' is not
available. The user can override this behavior with the '-force'
flag:
(gdb) cond -force 1 foo == 42
warning: failed to validate condition at location 1.1, disabling:
No symbol "foo" in current context.
(gdb) info breakpoints
Num Type Disp Enb Address What
1 breakpoint keep y <MULTIPLE>
stop only if foo == 42
1.1 N 0x0000000000001155 in main at test.c:5
Now the condition is accepted, but the location is automatically
disabled. If a future location has a context in which 'foo' is
available, that location would be enabled.
For the 'break' command, -force-condition has the same result:
(gdb) break test.c:5 -force-condition if foo == 42
warning: failed to validate condition at location 0x1169, disabling:
No symbol "foo" in current context.
Breakpoint 1 at 0x1169: file test.c, line 5.
gdb/ChangeLog:
2020-10-27 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* breakpoint.h (set_breakpoint_condition): Add a new bool parameter.
* breakpoint.c: Update the help text of the 'condition' and 'break'
commands.
(set_breakpoint_condition): Take a new bool parameter
to control whether condition definition should be forced even when
the condition expression is invalid in all of the current locations.
(condition_command): Update the call to 'set_breakpoint_condition'.
(find_condition_and_thread): Take the "-force-condition" flag into
account.
* linespec.c (linespec_keywords): Add "-force-condition" as an
element.
(FORCE_KEYWORD_INDEX): New #define.
(linespec_lexer_lex_keyword): Update to consider "-force-condition"
as a keyword.
* ada-lang.c (create_ada_exception_catchpoint): Ditto.
* guile/scm-breakpoint.c (gdbscm_set_breakpoint_condition_x): Ditto.
* python/py-breakpoint.c (bppy_set_condition): Ditto.
* NEWS: Mention the changes to the 'break' and 'condition' commands.
gdb/testsuite/ChangeLog:
2020-10-27 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* gdb.base/condbreak-multi-context.exp: Expand to test forcing
the condition.
* gdb.linespec/cpcompletion.exp: Update to consider the
'-force-condition' keyword.
* gdb.linespec/explicit.exp: Ditto.
* lib/completion-support.exp: Ditto.
gdb/doc/ChangeLog:
2020-10-27 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* gdb.texinfo (Set Breaks): Document the '-force-condition' flag
of the 'break'command.
* gdb.texinfo (Conditions): Document the '-force' flag of the
'condition' command.
Currently, for a conditional breakpoint, GDB checks if the condition
can be evaluated in the context of the first symtab and line (SAL).
In case of an error, defining the conditional breakpoint is aborted.
This prevents having a conditional breakpoint whose condition may
actually be meaningful for some of the location contexts. This patch
makes it possible to define conditional BPs by checking all location
contexts. If the condition is meaningful for even one context, the
breakpoint is defined. The locations for which the condition gives
errors are disabled.
The bp_location struct is introduced a new field, 'disabled_by_cond'.
This field denotes whether the location is disabled automatically
because the condition was non-evaluatable. Disabled-by-cond locations
cannot be enabled by the user. But locations that are not
disabled-by-cond can be enabled/disabled by the user manually as
before.
For a concrete example, consider 3 contexts of a function 'func'.
class Base
{
public:
int b = 20;
void func () {}
};
class A : public Base
{
public:
int a = 10;
void func () {}
};
class C : public Base
{
public:
int c = 30;
void func () {}
};
Note that
* the variable 'a' is defined only in the context of A::func.
* the variable 'c' is defined only in the context of C::func.
* the variable 'b' is defined in all the three contexts.
With the existing GDB, it's not possible to define a conditional
breakpoint at 'func' if the condition refers to 'a' or 'c':
(gdb) break func if a == 10
No symbol "a" in current context.
(gdb) break func if c == 30
No symbol "c" in current context.
(gdb) info breakpoints
No breakpoints or watchpoints.
With this patch, it becomes possible:
(gdb) break func if a == 10
warning: failed to validate condition at location 1, disabling:
No symbol "a" in current context.
warning: failed to validate condition at location 3, disabling:
No symbol "a" in current context.
Breakpoint 1 at 0x11b6: func. (3 locations)
(gdb) break func if c == 30
Note: breakpoint 1 also set at pc 0x11ce.
Note: breakpoint 1 also set at pc 0x11c2.
Note: breakpoint 1 also set at pc 0x11b6.
warning: failed to validate condition at location 1, disabling:
No symbol "c" in current context.
warning: failed to validate condition at location 2, disabling:
No symbol "c" in current context.
Breakpoint 2 at 0x11b6: func. (3 locations)
(gdb) info breakpoints
Num Type Disp Enb Address What
1 breakpoint keep y <MULTIPLE>
stop only if a == 10
1.1 N* 0x00000000000011b6 in Base::func() at condbreak-multi-context.cc:23
1.2 y 0x00000000000011c2 in A::func() at condbreak-multi-context.cc:31
1.3 N* 0x00000000000011ce in C::func() at condbreak-multi-context.cc:39
2 breakpoint keep y <MULTIPLE>
stop only if c == 30
2.1 N* 0x00000000000011b6 in Base::func() at condbreak-multi-context.cc:23
2.2 N* 0x00000000000011c2 in A::func() at condbreak-multi-context.cc:31
2.3 y 0x00000000000011ce in C::func() at condbreak-multi-context.cc:39
(*): Breakpoint condition is invalid at this location.
Here, uppercase 'N' denotes that the location is disabled because of
the invalid condition, as mentioned with a footnote in the legend of
the table. Locations that are disabled by the user are still denoted
with lowercase 'n'. Executing the code hits the breakpoints 1.2 and
2.3 as expected.
Defining a condition on an unconditional breakpoint gives the same
behavior above:
(gdb) break func
Breakpoint 1 at 0x11b6: func. (3 locations)
(gdb) cond 1 a == 10
warning: failed to validate condition at location 1.1, disabling:
No symbol "a" in current context.
warning: failed to validate condition at location 1.3, disabling:
No symbol "a" in current context.
(gdb) info breakpoints
Num Type Disp Enb Address What
1 breakpoint keep y <MULTIPLE>
stop only if a == 10
1.1 N* 0x00000000000011b6 in Base::func() at condbreak-multi-context.cc:23
1.2 y 0x00000000000011c2 in A::func() at condbreak-multi-context.cc:31
1.3 N* 0x00000000000011ce in C::func() at condbreak-multi-context.cc:39
(*): Breakpoint condition is invalid at this location.
Locations that are disabled because of a condition cannot be enabled
by the user:
...
(gdb) enable 1.1
Breakpoint 1's condition is invalid at location 1, cannot enable.
Resetting the condition enables the locations back:
...
(gdb) cond 1
Breakpoint 1's condition is now valid at location 1, enabling.
Breakpoint 1's condition is now valid at location 3, enabling.
Breakpoint 1 now unconditional.
(gdb) info breakpoints
Num Type Disp Enb Address What
1 breakpoint keep y <MULTIPLE>
1.1 y 0x00000000000011b6 in Base::func() at condbreak-multi-context.cc:23
1.2 y 0x00000000000011c2 in A::func() at condbreak-multi-context.cc:31
1.3 y 0x00000000000011ce in C::func() at condbreak-multi-context.cc:39
If a location is disabled by the user, a condition can still be defined
but the location will remain disabled even if the condition is meaningful
for the disabled location:
...
(gdb) disable 1.2
(gdb) cond 1 a == 10
warning: failed to validate condition at location 1.1, disabling:
No symbol "a" in current context.
warning: failed to validate condition at location 1.3, disabling:
No symbol "a" in current context.
(gdb) info breakpoints
Num Type Disp Enb Address What
1 breakpoint keep y <MULTIPLE>
stop only if a == 10
1.1 N* 0x00000000000011b6 in Base::func() at condbreak-multi-context.cc:23
1.2 n 0x00000000000011c2 in A::func() at condbreak-multi-context.cc:31
1.3 N* 0x00000000000011ce in C::func() at condbreak-multi-context.cc:39
(*): Breakpoint condition is invalid at this location.
The condition of a breakpoint can be changed. Locations'
enable/disable states are updated accordingly.
...
(gdb) cond 1 c == 30
warning: failed to validate condition at location 1.1, disabling:
No symbol "c" in current context.
Breakpoint 1's condition is now valid at location 3, enabling.
(gdb) info breakpoints
Num Type Disp Enb Address What
1 breakpoint keep y <MULTIPLE>
stop only if c == 30
1.1 N* 0x00000000000011b6 in Base::func() at condbreak-multi-context.cc:23
1.2 N* 0x00000000000011c2 in A::func() at condbreak-multi-context.cc:31
1.3 y 0x00000000000011ce in C::func() at condbreak-multi-context.cc:39
(*): Breakpoint condition is invalid at this location.
(gdb) cond 1 b == 20
Breakpoint 1's condition is now valid at location 1, enabling.
(gdb) info breakpoints
Num Type Disp Enb Address What
1 breakpoint keep y <MULTIPLE>
stop only if b == 20
1.1 y 0x00000000000011b6 in Base::func() at condbreak-multi-context.cc:23
1.2 n 0x00000000000011c2 in A::func() at condbreak-multi-context.cc:31
1.3 y 0x00000000000011ce in C::func() at condbreak-multi-context.cc:39
# Note that location 1.2 was disabled by the user previously.
If the condition expression is bad for all the locations, it will be
rejected.
(gdb) cond 1 garbage
No symbol "garbage" in current context.
For conditions that are invalid or valid for all the locations of a
breakpoint, the existing behavior is preserved.
Regression-tested on X86_64 Linux.
gdb/ChangeLog:
2020-10-27 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* breakpoint.h (class bp_location) <disabled_by_cond>: New field.
* breakpoint.c (set_breakpoint_location_condition): New function.
(set_breakpoint_condition): Disable a breakpoint location if parsing
the condition string gives an error.
(should_be_inserted): Update to consider the 'disabled_by_cond' field.
(build_target_condition_list): Ditto.
(build_target_command_list): Ditto.
(build_bpstat_chain): Ditto.
(print_one_breakpoint_location): Ditto.
(print_one_breakpoint): Ditto.
(breakpoint_1): Ditto.
(bp_location::bp_location): Ditto.
(locations_are_equal): Ditto.
(update_breakpoint_locations): Ditto.
(enable_disable_bp_num_loc): Ditto.
(init_breakpoint_sal): Use set_breakpoint_location_condition.
(find_condition_and_thread_for_sals): New static function.
(create_breakpoint): Call find_condition_and_thread_for_sals.
(location_to_sals): Call find_condition_and_thread_for_sals instead
of find_condition_and_thread.
gdb/testsuite/ChangeLog:
2020-10-27 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* gdb.base/condbreak-multi-context.cc: New file.
* gdb.base/condbreak-multi-context.exp: New file.
gdb/doc/ChangeLog:
2020-10-27 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* gdb.texinfo (Set Breaks): Document disabling of breakpoint
locations for which the breakpoint condition is invalid.
Use bool instead of int in struct solib_catchpoint and in init_catchpoint &
related functions.
gdb/ChangeLog:
* breakpoint.h (init_catchpoint): Change int parameter to bool.
(add_solib_catchpoint): Likewise.
* breakpoint.c (struct solib_catchpoint) <is_load>: Change type
to bool.
(add_solib_catchpoint): Change int parameter/variable to bool.
(catch_load_or_unload): Likewise.
(init_catchpoint): Likewise.
(create_fork_vfork_event_catchpoint): Likewise.
(catch_fork_command_1): Likewise.
(catch_exec_command_1): Likewise.
Change-Id: I1faf4506e9109f3ccdd7229ba766dc7d77aa7aa0
Consider test-case test.c:
...
$ cat test.c
int main (void) {
return 0;
L1:
(void)0;
}
...
Compiled with debug info:
...
$ gcc test.c -g
...
When attempting to set a breakpoint at L1, which is a label without address:
...
<1><f4>: Abbrev Number: 2 (DW_TAG_subprogram)
<f5> DW_AT_name : main
<2><115>: Abbrev Number: 3 (DW_TAG_label)
<116> DW_AT_name : L1
<119> DW_AT_decl_file : 1
<11a> DW_AT_decl_line : 5
<2><11b>: Abbrev Number: 0
...
we run into an internal-error:
...
$ gdb -batch a.out -ex "b main:L1"
linespec.c:3233: internal-error: void \
decode_line_full(const event_location*, int, program_space*, symtab*, \
int, linespec_result*, const char*, const char*): \
Assertion `result.size () == 1 || canonical->pre_expanded' failed.
A problem internal to GDB has been detected,
further debugging may prove unreliable.
...
Fix this by detecting the error condition in decode_line_full instead, and
throwing an error, such that we have instead:
...
(gdb) b main:L1
Location main:L1 not available
(gdb)
...
Unfortunately, to call event_location_to_string, which is used to get the
location name in the error message, we need to pass a non-const struct
event_location, because the call may cache the string in the struct (See
EL_STRING). So, we change the prototype of decode_line_full accordingly, and
everywhere this propages to.
Tested on x86_64-linux.
gdb/ChangeLog:
2020-08-28 Tom de Vries <tdevries@suse.de>
PR breakpoint/26544
* breakpoint.c (parse_breakpoint_sals): Remove const from struct
event_location.
(create_breakpoint): Same.
(base_breakpoint_decode_location): Same.
(bkpt_create_sals_from_location): Same.
(bkpt_decode_location): Same.
(bkpt_probe_create_sals_from_location): Same.
(bkpt_probe_decode_location): Same.
(tracepoint_create_sals_from_location): Same.
(tracepoint_decode_location): Same.
(tracepoint_probe_decode_location): Same.
(strace_marker_create_sals_from_location): Same.
(strace_marker_decode_location): Same.
(create_sals_from_location_default): Same.
(decode_location_default): Same.
* breakpoint.h (struct breakpoint_ops): Same.
(create_breakpoint): Same.
* linespec.h (decode_line_full): Same.
* linespec.c (decode_line_full): Same. Throw error if
result.size () == 0.
gdb/testsuite/ChangeLog:
2020-08-28 Tom de Vries <tdevries@suse.de>
* gdb.base/label-without-address.c: New test.
* gdb.base/label-without-address.exp: New file.
New in v3:
- Code cleanups based on reviews.
New in v2:
- Fixed misc problems based on reviews.
- Switched to using gdbarch_program_breakpoint_here_p as opposed to
gdbarch_insn_is_breakpoint.
- Fixed matching of brk instructions. Previously the mask was incorrect, which
was showing up as a few failures in the testsuite. Now it is clean.
- New testcase (separate patch).
- Moved program_breakpoint_here () to arch-utils.c and made it the default
implementation of gdbarch_program_breakpoint_here_p.
--
It was reported to me that program breakpoints (permanent ones inserted into
the code itself) other than the one GDB uses for AArch64 (0xd4200000) do not
generate visible stops when continuing, and GDB will continue spinning
infinitely.
This happens because GDB, upon hitting one of those program breakpoints, thinks
the SIGTRAP came from a delayed breakpoint hit...
(gdb) x/i $pc
=> 0x4005c0 <problem_function>: brk #0x90f
(gdb) c
Continuing.
infrun: clear_proceed_status_thread (process 14198)
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: proceed: resuming process 14198
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 14198] at 0x4005c0
infrun: infrun_async(1)
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 14198.14198.0 [process 14198],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: handle_inferior_event status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: stop_pc = 0x4005c0
infrun: delayed software breakpoint trap, ignoring
infrun: no stepping, continue
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 14198] at 0x4005c0
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 14198.14198.0 [process 14198],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: handle_inferior_event status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: stop_pc = 0x4005c0
infrun: delayed software breakpoint trap, ignoring
infrun: no stepping, continue
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 14198] at 0x4005c0
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 14198.14198.0 [process 14198],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: handle_inferior_event status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: stop_pc = 0x4005c0
infrun: delayed software breakpoint trap, ignoring
infrun: no stepping, continue
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 14198] at 0x4005c0
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 14198.14198.0 [process 14198],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: handle_inferior_event status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: stop_pc = 0x4005c0
infrun: delayed software breakpoint trap, ignoring
infrun: no stepping, continue
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 14198] at 0x4005c0
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 14198.14198.0 [process 14198],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
...
... which is not the case.
If the program breakpoint is one GDB recognizes, then it will stop when it
hits it.
(gdb) x/i $pc
=> 0x4005c0 <problem_function>: brk #0x0
(gdb) c
Continuing.
infrun: clear_proceed_status_thread (process 14193)
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: proceed: resuming process 14193
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 14193] at 0x4005c0
infrun: infrun_async(1)
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 14193.14193.0 [process 14193],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: handle_inferior_event status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: stop_pc = 0x4005c0
infrun: random signal (GDB_SIGNAL_TRAP)
infrun: stop_waiting
infrun: stop_all_threads
infrun: stop_all_threads, pass=0, iterations=0
infrun: process 14193 not executing
infrun: stop_all_threads, pass=1, iterations=1
infrun: process 14193 not executing
infrun: stop_all_threads done
Program received signal SIGTRAP, Trace/breakpoint trap.
problem_function () at brk_0.c:7
7 asm("brk %0\n\t" ::"n"(0x0));
infrun: infrun_async(0)
Otherwise GDB will keep trying to resume the inferior and will keep
seeing the SIGTRAP's, without stopping.
To the user it appears GDB has gone into an infinite loop, interruptible only
by Ctrl-C.
Also, windbg seems to use a different variation of AArch64 breakpoint compared
to GDB. This causes problems when debugging Windows on ARM binaries, when
program breakpoints are being used.
The proposed patch creates a new gdbarch method (gdbarch_program_breakpoint_here_p)
that tells GDB whether the underlying instruction is a breakpoint instruction
or not.
This is more general than only checking for the instruction GDB uses as
breakpoint.
The existing logic is still preserved for targets that do not implement this
new gdbarch method.
The end result is like so:
(gdb) x/i $pc
=> 0x4005c0 <problem_function>: brk #0x90f
(gdb) c
Continuing.
infrun: clear_proceed_status_thread (process 16417)
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: proceed: resuming process 16417
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 16417] at 0x4005c0
infrun: infrun_async(1)
infrun: prepare_to_wait
infrun: target_wait (-1.0.0, status) =
infrun: 16417.16417.0 [process 16417],
infrun: status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: handle_inferior_event status->kind = stopped, signal = GDB_SIGNAL_TRAP
infrun: stop_pc = 0x4005c0
infrun: random signal (GDB_SIGNAL_TRAP)
infrun: stop_waiting
infrun: stop_all_threads
infrun: stop_all_threads, pass=0, iterations=0
infrun: process 16417 not executing
infrun: stop_all_threads, pass=1, iterations=1
infrun: process 16417 not executing
infrun: stop_all_threads done
Program received signal SIGTRAP, Trace/breakpoint trap.
problem_function () at brk.c:7
7 asm("brk %0\n\t" ::"n"(0x900 + 0xf));
infrun: infrun_async(0)
gdb/ChangeLog:
2020-01-29 Luis Machado <luis.machado@linaro.org>
* aarch64-tdep.c (BRK_INSN_MASK): Define to 0xffe0001f.
(BRK_INSN_MASK): Define to 0xd4200000.
(aarch64_program_breakpoint_here_p): New function.
(aarch64_gdbarch_init): Set gdbarch_program_breakpoint_here_p hook.
* arch-utils.c (default_program_breakpoint_here_p): Moved from
breakpoint.c.
* arch-utils.h (default_program_breakpoint_here_p): Moved from
breakpoint.h
* breakpoint.c (bp_loc_is_permanent): Changed return type to bool and
call gdbarch_program_breakpoint_here_p.
(program_breakpoint_here): Moved to arch-utils.c, renamed to
default_program_breakpoint_here_p, changed return type to bool and
simplified.
* breakpoint.h (program_breakpoint_here): Moved prototype to
arch-utils.h, renamed to default_program_breakpoint_here_p and changed
return type to bool.
* gdbarch.c: Regenerate.
* gdbarch.h: Regenerate.
* gdbarch.sh (program_breakpoint_here_p): New method.
* infrun.c (handle_signal_stop): Call
gdbarch_program_breakpoint_here_p.
The documentation for make-breakpoint from the Guile API and the `spec'
variant of the gdb.Breakpoint constructor from the Python API state that
the format acceptable for location strings is the same as that accepted
by the break command. However, using the -probe qualifier at the
beginning of the location string causes a GDB internal error as it
attempts to decode a probe location in the wrong code path. Without this
functionality, there doesn't appear to be another way to set breakpoints
on probe points from Python or Guile scripts.
This patch introduces a new helper function that returns a
breakpoint_ops instance appropriate for a parsed location and updates
the Guile and Python bindings to use said function, rather than the
current hard-coded use of bkpt_breakpoint_ops. Since this logic is
duplicated in the handling of the `break' and `trace' commands, those
are also updated to call into the new helper function.
gdb/ChangeLog:
2019-12-10 George Barrett <bob@bob131.so>
Fix scripted probe breakpoints.
* breakpoint.c (tracepoint_probe_breakpoint_ops): Move
declaration forward.
(breakpoint_ops_for_event_location_type)
(breakpoint_ops_for_event_location): Add function definitions.
(break_command_1, trace_command): Use
breakpoint_ops_for_event_location.
* breakpoint.h (breakpoint_ops_for_event_location): Add function
declarations.
* guile/scm-breakpoint.c (gdbscm_register_breakpoint_x): Use
breakpoint_ops_for_event_location.
* python/py-breakpoint.c (bppy_init): Use
breakpoint_ops_for_event_location.
gdb/testsuite/ChangeLog:
2019-12-10 George Barrett <bob@bob131.so>
Test scripted probe breakpoints.
* gdb.guile/scm-breakpoint.c (main): Add probe point.
* gdb.python/py-breakpoint.c (main): Likewise.
* gdb.guile/scm-breakpoint.exp (test_bkpt_probe): Add probe
specifier test.
* gdb.python/py-breakpoint.exp (test_bkpt_probe): Likewise.
rbreak_command_wrapper is unused, so remove it. And while at it, remove
other declarations around it.
gdb/ChangeLog:
* breakpoint.h (hbreak_command_wrapper, thbreak_command_wrapper,
rbreak_command_wrapper): Remove.
* symtab.c (rbreak_command_wrapper): Remove.
Change-Id: If9782f205e4913f8dfc5beeaa526544f25e099c6
These int fields have been converted to bool, so their doc should say
"true" and not "nonzero".
gdb/ChangeLog:
* breakpoint.h (bp_location) <inserted, permanent, duplicate>:
Change "nonzero" to "true" in documentation.
This changes breakpoint::filter to be a unique_xmalloc_ptr, removing
an explicit xfree, as well as a use of a "release" method.
gdb/ChangeLog
2019-08-06 Tom Tromey <tromey@adacore.com>
* breakpoint.c (init_breakpoint_sal): Update.
(breakpoint): Update.
* breakpoint.h (struct breakpoint) <filter>: Now a
unique_xmalloc_ptr.
This includes changing the FILTER parameters of two functions
accordingly. I also tried to normalize the function comments to our
current standards.
gdb/ChangeLog:
* breakpoint.c (is_hardware_watchpoint): Remove
forward-declaration.
(is_masked_watchpoint): Change return type to bool.
(is_tracepoint): Likewise.
(is_breakpoint): Likewise.
(is_hardware_watchpoint): Likewise.
(is_watchpoint): Likewise.
(is_no_memory_software_watchpoint): Likewise.
(is_catchpoint): Likewise.
(breakpoint_1): Make FILTER parameter's return type bool.
is_masked_watchpoint): Change return type to bool.
(save_breakpoints): Make FILTER parameter's return type bool.
* breakpoint.h (is_breakpoint): Change return type to bool.
(is_watchpoint): Likewise.
(is_catchpoint): Likewise.
(is_tracepoint): Likewise.