Consider the case of the user doing "step" in thread 2, while thread 1
had previously stopped for a breakpoint. In order to make progress,
GDB makes thread 1 step over its breakpoint first (with all other
threads stopped), and once that is over, thread 2 then starts stepping
(with thread 1 and all others running free, by default). If GDB
didn't do that, thread 1 would just trip on the same breakpoint
immediately again. This is what the prepare_to_proceed /
deferred_step_ptid code is all about.
However, deferred_step_ptid code resumes the target with:
resume (1, GDB_SIGNAL_0);
prepare_to_wait (ecs);
return;
Recall we were just stepping over a breakpoint when we get here. That
means that _nothing_ had installed breakpoints yet! If there's
another breakpoint just after the breakpoint that was just stepped,
we'll miss it. The fix for that would be to use keep_going instead.
However, there are more problems. What if the instruction that was
just single-stepped triggers a watchpoint? Currently, GDB just
happily resumes the thread, losing that too...
Missed watchpoints will need yet further fixes, but we should keep
those in mind.
So the fix must be to let the trap fall through the regular bpstat
handling, and only if no breakpoint, watchpoint, etc. claims the trap,
shall we switch back to the stepped thread.
Now, nowadays, we have code at the tail end of trap handling that does
exactly that -- switch back to the stepped thread
(switch_back_to_the_stepped_thread).
So the deferred_step_ptid code is just standing in the way, and can
simply be eliminated, fixing bugs in the process. Sweet.
The comment about spurious "Switching to ..." made me pause, but is
actually stale nowadays. That isn't needed anymore.
previous_inferior_ptid used to be re-set at each (internal) event, but
now it's only touched in proceed and normal stop.
The two tests added by this patch fail without the fix.
Tested on x86_64 Fedora 17 (also against my software single-stepping
on x86 branch).
gdb/
2014-03-20 Pedro Alves <palves@redhat.com>
* infrun.c (previous_inferior_ptid): Adjust comment.
(deferred_step_ptid): Delete.
(infrun_thread_ptid_changed, prepare_to_proceed)
(init_wait_for_inferior): Adjust.
(handle_signal_stop): Delete deferred_step_ptid handling.
gdb/testsuite/
2014-03-20 Pedro Alves <palves@redhat.com>
* gdb.threads/step-over-lands-on-breakpoint.c: New file.
* gdb.threads/step-over-lands-on-breakpoint.exp: New file.
linker testsuite failures were showing up for the cris target. Fixed by
this patch.
* readelf.c (process_version_sections): Fix off-by-one error in
previous delta.
Unless pointer_equality_needed is set then set st_value to be zero
for undefined symbols.
bfd/ChangeLog:
2014-03-20 Will Newton <will.newton@linaro.org>
PR ld/16715
* elf32-arm.c (elf32_arm_check_relocs): Set
pointer_equality_needed for absolute references within
executable links.
(elf32_arm_finish_dynamic_symbol): Set st_value to zero
unless pointer_equality_needed is set.
ld/testsuite/ChangeLog:
2014-03-20 Will Newton <will.newton@linaro.org>
* ld-arm/ifunc-14.rd: Update symbol values.
send readelf into an infinite loop.
* readelf.c (process_version_sections): Prevent an infinite loop
when the vn_next field is zero but there are still entries to be
processed.
and %hstick_enable to the Sparc assembler.
* config/tc-sparc.c (hpriv_reg_table): Added entries for
%hstick_offset and %hstick_enable.
* doc/c-sparc.texi (Sparc-Regs): Document the %hstick_offset and
%hstick_enable hyperprivileged registers.
* sparc-dis.c (v9_hpriv_reg_names): Names for %hstick_offset and
%hstick_enable added.
* gas/sparc/rdhpr.s: Test rd %hstick_offset and %hstick_enable.
* gas/sparc/rdhpr.d: Likewise.
* gas/sparc/wrhpr.s: Test wr %hstick_offset and %hstick_enable.
* gas/sparc/wrhpr.d: Likewise.
There's no reason not to enable this test anymore.
Even if the current output isn't ideal (we mess up the prompt), it's what
we have today. We can adjust the test if the output improves.
gdb/testsuite/
2014-03-19 Pedro Alves <palves@redhat.com>
* gdb.base/async.exp: Remove early return.
This test is currently racy:
PASS: gdb.base/async.exp: step&
stepi&
(gdb) 0x0000000000400547 14 x = 5; x = 5;
completed.
PASS: gdb.base/async.exp: stepi&
nexti&
(gdb) 15 y = 3;
completed.FAIL: gdb.base/async.exp: nexti&
The problem is here:
-re "^$command\r\n${before_prompt}${gdb_prompt}${after_prompt}completed\.\r\n" {
pass "$command"
}
-re "$gdb_prompt.*completed\.$" {
fail "$command"
}
Note how the fail pattern is a subset of the pass pattern. If the
expect buffer happens to end up with:
"^$command\r\n${before_prompt}${gdb_prompt}${after_prompt}completed\."
that is, the final "\r\n" has't reached the expect buffer yet, but
"completed." has, then the fail pattern matches...
gdb/testsuite/
2014-03-19 Pedro Alves <palves@redhat.com>
* gdb.base/async.exp (test_background): Expect \r\n after
"completed." in the fail pattern.
All the tests here follow the same pattern (and they all have the same
problem, not fixed here yet). Add a new procedure, factoring out the
pattern to a simple place.
gdb/testsuite/
2014-03-19 Pedro Alves <palves@redhat.com>
* gdb.base/async.exp (test_background): New procedure.
Use it for all background execution command tests.
Currently the test assumes that "stepi" over:
13 x = 5;
end up somewhere midline. But, (at least) on x86, that assignment
ends up compiled as just one movl instruction, so a stepi stops at the
next line already:
completed.
PASS: gdb.base/async.exp: step &
step&
(gdb) foo () at ../../../src/gdb/testsuite/gdb.base/async.c:13
13 x = 5;
completed.
PASS: gdb.base/async.exp: step &
stepi&
(gdb) 14 y = 3;
completed.
FAIL: gdb.base/async.exp: (timeout) stepi &
nexti&
(gdb) 16 return x + y;
completed.
FAIL: gdb.base/async.exp: (timeout) nexti &
finish&
Run till exit from #0 foo () at ../../../src/gdb/testsuite/gdb.base/async.c:16
This patch fixes it, by making sure there's more than one instruction
in that line.
gdb/testsuite/
2014-03-19 Pedro Alves <palves@redhat.com>
* gdb.base/async.c (foo): Make 'x' volatile. Write to it twice in
the same line.
gdb/testsuite/
2014-03-19 Pedro Alves <palves@redhat.com>
* gdb.base/async.c (main): Add "jump here" and "until here" line
marker comments.
* gdb.base/async.exp (jump_here): New global.
(jump& test): Use it.
(until_here): New global.
(until& test): Use it.
Many eons ago, async was only implemented in the remote target, and
you'd activate it by doing "target async" rather than "target remote".
That's long gone now, replaced by "set target-async on".
gdb/testsuite/
2014-03-19 Pedro Alves <palves@redhat.com>
* gdb.base/async.exp: Don't frob gdb_protocol.
should work for all types of input .rsrc section.
* peXXigen.c (rsrc_process_section): Add code to scan input
sections and record their lengths. Use these lengths to find the
start of each merged .rsrc section.
* scripttempl/pe.sc (R_RSRC): Fix default-manifest exclusion.
(.rsrc): Add SUBALIGN(4). Remove SORT.
* scripttempl/pep.sc: Likewise.
* config/tc-arm.c (codecomposer_syntax): New flag that states whether the
CCS syntax compatibility mode is on or off.
(asmfunc_states): New enum to represent the asmfunc directive state.
(asmfunc_state): New variable holding the asmfunc directive state.
(comment_chars): Rename to arm_comment_chars.
(line_separator_chars): Rename to arm_line_separator_chars.
(s_ccs_ref): New function that handles the .ref directive.
(asmfunc_debug): New function.
(s_ccs_asmfunc): New function that handles the .asmfunc directive.
(s_ccs_endasmfunc): New function that handles the .endasmfunc directive.
(s_ccs_def): New function that handles the .def directive.
(tc_start_label_without_colon): New function.
(md_pseudo_table): Added new CCS directives.
(arm_ccs_mode): New function that handles the -mccs command line option.
(arm_long_opts): Added new -mccs command line option.
* config/tc-arm.h (LABELS_WITHOUT_COLONS): New macro.
(TC_START_LABEL_WITHOUT_COLON): New macro.
(tc_start_label_without_colon): Added extern function declaration.
(tc_comment_chars): Define.
(tc_line_separator_chars): Define.
* app.c (do_scrub_begin): Use tc_line_separator_chars, if defined.
* read.c (read_begin): Likewise.
* doc/as.texinfo: Add documentation for the -mccs command line
option.
* doc/c-arm.texi: Likewise.
* doc/internals.texi: Document tc_line_separator_chars.
* NEWS: Mention the new feature.
* gas/arm/ccs.s: New test case.
* gas/arm/ccs.d: New expected disassembly.
* rx-decode.opc (bwl): Allow for bogus instructions with a size
field of 3.
(sbwl, ubwl, SCALE): Likewise.
* rx-decode.c: Regenerate.
* gas/rx/mov.d: Update expected disassembly.
gdb/
2014-03-18 Jan Kratochvil <jan.kratochvil@redhat.com>
PR gdb/15358
* defs.h (sync_quit_force_run): New declaration.
(QUIT): Check also SYNC_QUIT_FORCE_RUN.
* event-top.c (async_sigterm_handler): New declaration.
(async_sigterm_token): New variable.
(async_init_signals): Create also async_sigterm_token.
(async_sigterm_handler): New function.
(sync_quit_force_run): New variable.
(handle_sigterm): Replace quit_force call by other calls.
* utils.c (quit): Call quit_force if SYNC_QUIT_FORCE_RUN.
gdb/testsuite/
2014-03-18 Jan Kratochvil <jan.kratochvil@redhat.com>
PR gdb/15358
* gdb.base/gdb-sigterm.c: New file.
* gdb.base/gdb-sigterm.exp: New file.
Message-ID: <20140316135334.GA30698@host2.jankratochvil.net>
This change corrects GPR frame offset calculation for the e500v2
processor. On this target, featuring the SPE APU, GPRs are 64-bit and
are held in stack frames whole with the use of `evstdd' and `evldd'
instructions. Their integer 32-bit part occupies the low-order word and
therefore its offset varies between the two endiannesses possible.
* rs6000-tdep.c (rs6000_frame_cache): Correct little-endian GPR
offset into SPE pseudo registers.
Part of PR gdb/13860 is about the mi-solib.exp test's output being
different in sync vs async modes.
sync:
>./gdb -nx -q ./testsuite/gdb.mi/solib-main -ex "set stop-on-solib-events 1" -ex "set target-async off" -i=mi
=thread-group-added,id="i1"
~"Reading symbols from /home/pedro/gdb/mygit/build/gdb/testsuite/gdb.mi/solib-main..."
~"done.\n"
(gdb)
&"start\n"
~"Temporary breakpoint 1 at 0x400608: file ../../../src/gdb/testsuite/gdb.mi/solib-main.c, line 21.\n"
=breakpoint-created,bkpt={number="1",type="breakpoint",disp="del",enabled="y",addr="0x0000000000400608",func="main",file="../../../src/gdb/testsuite/gdb.mi/solib-main.c",fullname="/home/pedro/gdb/mygit/src/gdb/testsuite/gdb.mi/solib-main.c",line="21",times="0",original-location="main"}
~"Starting program: /home/pedro/gdb/mygit/build/gdb/testsuite/gdb.mi/solib-main \n"
=thread-group-started,id="i1",pid="17724"
=thread-created,id="1",group-id="i1"
^running
*running,thread-id="all"
(gdb)
=library-loaded,id="/lib64/ld-linux-x86-64.so.2",target-name="/lib64/ld-linux-x86-64.so.2",host-name="/lib64/ld-linux-x86-64.so.2",symbols-loaded="0",thread-group="i1"
~"Stopped due to shared library event (no libraries added or removed)\n"
*stopped,reason="solib-event",frame={addr="0x000000379180f990",func="_dl_debug_state",args=[],from="/lib64/ld-linux-x86-64.so.2"},thread-id="1",stopped-threads="all",core="3"
(gdb)
async:
>./gdb -nx -q ./testsuite/gdb.mi/solib-main -ex "set stop-on-solib-events 1" -ex "set target-async on" -i=mi
=thread-group-added,id="i1"
~"Reading symbols from /home/pedro/gdb/mygit/build/gdb/testsuite/gdb.mi/solib-main..."
~"done.\n"
(gdb)
start
&"start\n"
~"Temporary breakpoint 1 at 0x400608: file ../../../src/gdb/testsuite/gdb.mi/solib-main.c, line 21.\n"
=breakpoint-created,bkpt={number="1",type="breakpoint",disp="del",enabled="y",addr="0x0000000000400608",func="main",file="../../../src/gdb/testsuite/gdb.mi/solib-main.c",fullname="/home/pedro/gdb/mygit/src/gdb/testsuite/gdb.mi/solib-main.c",line="21",times="0",original-location="main"}
~"Starting program: /home/pedro/gdb/mygit/build/gdb/testsuite/gdb.mi/solib-main \n"
=thread-group-started,id="i1",pid="17729"
=thread-created,id="1",group-id="i1"
^running
*running,thread-id="all"
=library-loaded,id="/lib64/ld-linux-x86-64.so.2",target-name="/lib64/ld-linux-x86-64.so.2",host-name="/lib64/ld-linux-x86-64.so.2",symbols-loaded="0",thread-group="i1"
(gdb)
*stopped,reason="solib-event",thread-id="1",stopped-threads="all",core="1"
For now, let's focus only on the *stopped event. We see that the
async output is missing frame info. And this causes a test failure in
async mode, as "mi_expect_stop solib-event" wants to see the frame
info.
However, if we compare the event output when a real MI execution
command is used, compared to a CLI command (e.g., run vs -exec-run,
next vs -exec-next, etc.), we see:
>./gdb -nx -q ./testsuite/gdb.mi/solib-main -ex "set stop-on-solib-events 1" -ex "set target-async off" -i=mi
=thread-group-added,id="i1"
~"Reading symbols from /home/pedro/gdb/mygit/build/gdb/testsuite/gdb.mi/solib-main..."
~"done.\n"
(gdb)
r
&"r\n"
~"Starting program: /home/pedro/gdb/mygit/build/gdb/testsuite/gdb.mi/solib-main \n"
=thread-group-started,id="i1",pid="17751"
=thread-created,id="1",group-id="i1"
^running
*running,thread-id="all"
(gdb)
=library-loaded,id="/lib64/ld-linux-x86-64.so.2",target-name="/lib64/ld-linux-x86-64.so.2",host-name="/lib64/ld-linux-x86-64.so.2",symbols-loaded="0",thread-group="i1"
~"Stopped due to shared library event (no libraries added or removed)\n"
*stopped,reason="solib-event",frame={addr="0x000000379180f990",func="_dl_debug_state",args=[],from="/lib64/ld-linux-x86-64.so.2"},thread-id="1",stopped-threads="all",core="3"
(gdb)
-exec-run
=thread-exited,id="1",group-id="i1"
=thread-group-exited,id="i1"
=library-unloaded,id="/lib64/ld-linux-x86-64.so.2",target-name="/lib64/ld-linux-x86-64.so.2",host-name="/lib64/ld-linux-x86-64.so.2",thread-group="i1"
=thread-group-started,id="i1",pid="17754"
=thread-created,id="1",group-id="i1"
^running
*running,thread-id="all"
(gdb)
=library-loaded,id="/lib64/ld-linux-x86-64.so.2",target-name="/lib64/ld-linux-x86-64.so.2",host-name="/lib64/ld-linux-x86-64.so.2",symbols-loaded="0",thread-group="i1"
*stopped,reason="solib-event",thread-id="1",stopped-threads="all",core="1"
=thread-selected,id="1"
(gdb)
As seen above, with MI commands, the *stopped event _doesn't_ have
frame info. This is because normal_stop, as commanded by the result
of bpstat_print, skips printing frame info in this case (it's an
"event", not a "breakpoint"), and when the interpreter is MI,
mi_on_normal_stop skips calling print_stack_frame, as the normal_stop
call was already done with the MI uiout. This explains why the async
output is different even with a CLI command. Its because in async
mode, the mi_on_normal_stop path is always taken; it is always reached
with the MI uiout, because the stop is handled from the event loop,
instead of from within `proceed -> wait_for_inferior -> normal_stop'
with the interpreter overridden, as in sync mode.
This patch fixes the issue by making all cases output the same
*stopped event, by factoring out the print code from normal_stop, and
using it from mi_on_normal_stop as well. I chose the *stopped output
without a frame, mainly because that is what you already get if you
use MI execution commands, the commands frontends are supposed to use
(except when implementing a console). This patch makes it simpler to
tweak the MI output differently if desired, as we only have to change
the centralized print_stop_event (taking into account whether the
uiout is MI-like), and all different modes will change accordingly.
Tested on x86_64 Fedora 17, no regressions. The mi-solib.exp test no
longer fails in async mode with this patch, so the patch removes the
kfail.
2014-03-18 Pedro Alves <palves@redhat.com>
PR gdb/13860
* inferior.h (print_stop_event): Declare.
* infrun.c (print_stop_event): New, factored out from ...
(normal_stop): ... this.
* mi/mi-interp.c (mi_on_normal_stop): Use print_stop_event instead
of bpstat_print/print_stack_frame.
2014-03-18 Pedro Alves <palves@redhat.com>
PR gdb/13860
* gdb.mi/mi-solib.exp: Remove gdb/13860 kfail.
* lib/mi-support.exp (mi_expect_stop): Add special handling for
solib-event.
The destructor code in ui-out.c has a latent bug, which is hidden by
the fact that nothing uses this right now. This patch fixes the
problem. The bug is that we don't always clear a pointer in the
ui-out object, leading to a bad free.
2014-03-17 Tom Tromey <tromey@redhat.com>
* ui-out.c (clear_table, ui_out_new): Clear uiout->table.id.
Consider the following declarations:
type Packed_Array is array (Natural range <>) of Boolean;
pragma Pack (Packed_Array);
function Make (H, L : Natural) return Packed_Array is
begin
return (H .. L => False);
end Make;
A1 : Packed_Array := Make (1, 2);
A2 : Packed_Array renames A1;
One possible DWARF translation for A2 is:
<3><1e4>: Abbrev Number: 21 (DW_TAG_variable)
<1e5> DW_AT_name : a2
<1ea> DW_AT_type : <0x1d9>
<3><1d9>: Abbrev Number: 22 (DW_TAG_const_type)
<1da> DW_AT_type : <0x1de>
<3><1de>: Abbrev Number: 23 (DW_TAG_reference_type)
<1e0> DW_AT_type : <0x1a3>
<3><1a3>: Abbrev Number: 17 (DW_TAG_array_type)
<1a4> DW_AT_name : foo__Ta1S___XP1
<1a8> DW_AT_GNAT_descriptive_type: <0x16b>
<3><16b>: Abbrev Number: 6 (DW_TAG_typedef)
<16c> DW_AT_name : foo__Ta1S
<172> DW_AT_type : <0x176>
<3><176>: Abbrev Number: 17 (DW_TAG_array_type)
<177> DW_AT_name : foo__Ta1S
<17b> DW_AT_GNAT_descriptive_type: <0x223>
Here, foo__Ta1S___XP1 is the type used for the code generation while
foo__Ta1S is the source-level type. Both form a valid GNAT encoding for
a packed array type.
Trying to print A2 (1) can make GDB crash. This is because A2 is defined
as a reference to a GNAT encoding for a packed array. When decoding
constrained packed arrays, the ada_coerce_ref subprogram follows
references and returns a fixed type from the target type, peeling
the GNAT encoding for packed arrays. The remaining code assumes that
the resulting type is still such an encoding while we only have
a standard GDB array type, hence the crash:
arr = ada_coerce_ref (arr);
[...]
type = decode_constrained_packed_array_type (value_type (arr));
decode_constrained_packed_array_type assumes that its argument is
such an encoding. From its front comment:
/* The array type encoded by TYPE, where
ada_is_constrained_packed_array_type (TYPE). */
This patch simply replaces the call to ada_coerce_ref with a call
to coerce_ref in order to avoid prematurely transforming
the packed array type as a side-effect. This way, the remaining code
will always work with a GNAT encoding.
gdb/ChangeLog:
* ada-lang.c (decode_constrained_packed_array): Perform a
minimal coercion for reference with coerce_ref instead of
ada_coerce_ref.
This fixes a build failure against Python 2.4 by casting away "const"
on the second argument to PyObject_GetAttrString. Similar casts to
support Python 2.4 were already present in a number of other places.
gdb/
2014-03-16 Ulrich Weigand <uweigand@de.ibm.com>
* python/py-value.c (get_field_flag): Cast flag_name argument to
PyObject_GetAttrString to support Python 2.4.
gdb/
2014-03-14 Jan Kratochvil <jan.kratochvil@redhat.com>
* MAINTAINERS (The Official FSF-appointed GDB Maintainers)
(Global Maintainers): Remove Jan Kratochvil.
PR sim/8388
* armemu.c (WriteR15Load): New function. Determines if the state
can be changed upon a write to R15.
(LoadMult): Use WriteR15Load.
* armemu.h (WRITEDESTB): Use WriteR15Load.
