This fixes gdbarch matching, making sure one for the opposite compressed
ISA variation is not chosen. That in turn makes "set mips compression"
work; right now the setting sticks to the initial value, either inferred
from the ELF header of the binary first loaded or the default value if
no binary has been used. This only affects debugging with no symbol
table available or no binary chosen at all, as otherwise symbol
annotations determine the compressed ISA variation.
* mips-tdep.c (mips_gdbarch_init): Also check the compressed ISA
variation in gdbarch matching.
This removes the using_exec_ops global from exec.c, in favor of
querying the target stack directly using target_is_pushed. This is
more in keeping with other code in gdb, and is also more future-proof
as it is more multi-target-ready.
Built and regtested on x86-64 Fedora 20.
2014-07-25 Tom Tromey <tromey@redhat.com>
* exec.c (using_exec_ops): Remove.
(exec_close_1): Update. Remove extraneous block, reindent.
(add_target_sections): Use target_is_pushed.
A previous patch added a new parameter to clear_proceed_status, but
forgot to update a few callers.
Tested by building on x86_64 Fedora 20, with --enable-targets=all.
gdb/
2014-07-25 Pedro Alves <palves@redhat.com>
* go32-nat.c (go32_create_inferior): Pass 0 to clear_proceed_status.
* monitor.c (monitor_create_inferior): Likewise.
* remote-m32r-sdi.c (m32r_create_inferior): Likewise.
* remote-sim.c (gdbsim_create_inferior): Likewise.
* solib-irix.c (irix_solib_create_inferior_hook): Likewise.
* solib-osf.c (osf_solib_create_inferior_hook): Likewise.
* windows-nat.c (do_initial_windows_stuff): Likewise.
Currently, GDB can pass a signal to the wrong thread in several
different but related scenarios.
E.g., if thread 1 stops for signal SIGFOO, the user switches to thread
2, and then issues "continue", SIGFOO is actually delivered to thread
2, not thread 1. This obviously messes up programs that use
pthread_kill to send signals to specific threads.
This has been a known issue for a long while. Back in 2008 when I
made stop_signal be per-thread (2020b7ab), I kept the behavior -- see
code in 'proceed' being removed -- wanting to come back to it later.
The time has finally come now.
The patch fixes this -- on resumption, intercepted signals are always
delivered to the thread that had intercepted them.
Another example: if thread 1 stops for a breakpoint, the user switches
to thread 2, and then issues "signal SIGFOO", SIGFOO is actually
delivered to thread 1, not thread 2, because 'proceed' first switches
to thread 1 to step over its breakpoint... If the user deletes the
breakpoint before issuing "signal FOO", then the signal is delivered
to thread 2 (the current thread).
"signal SIGFOO" can be used for two things: inject a signal in the
program while the program/thread had stopped for none, bypassing
"handle nopass"; or changing/suppressing a signal the program had
stopped for. These scenarios are really two faces of the same coin,
and GDB can't really guess what the user is trying to do. GDB might
have intercepted signals in more than one thread even (see the new
signal-command-multiple-signals-pending.exp test). At least in the
inject case, it's obviously clear to me that the user means to deliver
the signal to the currently selected thread, so best is to make the
command's behavior consistent and easy to explain.
Then, if the user is trying to suppress/change a signal the program
had stopped for instead of injecting a new signal, but, the user had
changed threads meanwhile, then she will be surprised that with:
(gdb) continue
Thread 1 stopped for signal SIGFOO.
(gdb) thread 2
(gdb) signal SIGBAR
... GDB actually delivers SIGFOO to thread 1, and SIGBAR to thread 2
(with scheduler-locking off, which is the default, because then
"signal" or any other resumption command resumes all threads).
So the patch makes GDB detect that, and ask for confirmation:
(gdb) thread 1
[Switching to thread 1 (Thread 10979)]
(gdb) signal SIGUSR2
Note:
Thread 3 previously stopped with signal SIGUSR2, User defined signal 2.
Thread 2 previously stopped with signal SIGUSR1, User defined signal 1.
Continuing thread 1 (the current thread) with specified signal will
still deliver the signals noted above to their respective threads.
Continue anyway? (y or n)
All these scenarios are covered by the new tests.
Tested on x86_64 Fedora 20, native and gdbserver.
gdb/
2014-07-25 Pedro Alves <palves@redhat.com>
* NEWS: Mention signal passing and "signal" command changes.
* gdbthread.h (struct thread_suspend_state) <stop_signal>: Extend
comment.
* breakpoint.c (until_break_command): Adjust clear_proceed_status
call.
* infcall.c (run_inferior_call): Adjust clear_proceed_status call.
* infcmd.c (proceed_thread_callback, continue_1, step_once)
(jump_command): Adjust clear_proceed_status call.
(signal_command): Warn if other thread that are resumed have
signals that will be delivered. Adjust clear_proceed_status call.
(until_next_command, finish_command)
(proceed_after_attach_callback, attach_command_post_wait)
(attach_command): Adjust clear_proceed_status call.
* infrun.c (proceed_after_vfork_done): Likewise.
(proceed_after_attach_callback): Adjust comment.
(clear_proceed_status_thread): Clear stop_signal if not in pass
state.
(clear_proceed_status_callback): Delete.
(clear_proceed_status): New 'step' parameter. Only clear the
proceed status of threads the command being prepared is about to
resume.
(proceed): If passed in an explicit signal, override stop_signal
with it. Don't pass the last stop signal to the thread we're
resuming.
(init_wait_for_inferior): Adjust clear_proceed_status call.
(switch_back_to_stepped_thread): Clear the signal if it should not
be passed.
* infrun.h (clear_proceed_status): New 'step' parameter.
(user_visible_resume_ptid): Add comment.
* linux-nat.c (linux_nat_resume_callback): Don't check whether the
signal is in pass state.
* remote.c (append_pending_thread_resumptions): Likewise.
* mi/mi-main.c (proceed_thread): Adjust clear_proceed_status call.
gdb/doc/
2014-07-25 Pedro Alves <palves@redhat.com>
Eli Zaretskii <eliz@gnu.org>
* gdb.texinfo (Signaling) <signal command>: Explain what happens
with multi-threaded programs.
gdb/testsuite/
2014-07-25 Pedro Alves <palves@redhat.com>
* gdb.threads/signal-command-handle-nopass.c: New file.
* gdb.threads/signal-command-handle-nopass.exp: New file.
* gdb.threads/signal-command-multiple-signals-pending.c: New file.
* gdb.threads/signal-command-multiple-signals-pending.exp: New file.
* gdb.threads/signal-delivered-right-thread.c: New file.
* gdb.threads/signal-delivered-right-thread.exp: New file.
I happened to notice that a couple of macros in target.h weren't
properly using parens and as a result had a strange definition.
This patch adds the parens and then fixes the macros to be written as
must have been intended.
Tested by rebuilding.
I'm pushing this as obvious.
2014-07-25 Tom Tromey <tromey@redhat.com>
* target.h (target_stopped_data_address)
(target_watchpoint_addr_within_range): Use "->", not ".". Fix
parentheses.
This patch adds additional comments about the conversion of addresses to
pointers and vice-versa on AVR.
Special conversion needs to be done when dealing with an address in the
flash address space, where both code and read-only data can be stored.
Code and data pointers to flash are not addressed the same way:
A code pointer is 16 bit addressed. A data pointer is 8 bit addressed,
even if the data is in flash.
2014-07-25 Pierre Langlois <pierre.langlois@embecosm.com>
* avr-tdep.c (avr_address_to_pointer): Clarify the conversion in the
comments.
(avr_pointer_to_address): Likewise.
Jan pointed out in
<https://sourceware.org/ml/gdb-patches/2014-07/msg00553.html> that
these testcases have racy results:
gdb.base/double-prompt-target-event-error.exp
gdb.base/paginate-after-ctrl-c-running.exp
gdb.base/paginate-bg-execution.exp
gdb.base/paginate-execution-startup.exp
gdb.base/paginate-inferior-exit.exp
This is easily reproducible with "read1" from:
[reproducer for races of expect incomplete reads]
http://sourceware.org/bugzilla/show_bug.cgi?id=12649
The '-notransfer -re "<return>" { exp_continue }' trick in the current
tests doesn't actually work.
The issue that led to the -notransfer trick was that
"---Type <return> to continue, or q <return> to quit---"
has two "<return>"s. If one wants gdb_test_multiple to not hit the
built-in "<return>" match that results in FAIL, one has to expect the
pagination prompt in chunks, first up to the first "<return>", then
again, up to the second. Something around these lines:
gdb_test_multiple "" $test {
-re "<return>" {
exp_continue
}
-re "to quit ---" {
pass $test
}
}
The intent was for -notransfer+exp_continue to make expect fetch more
input, and rerun the matches against the now potentially fuller
buffer, and then eventually the -re that includes the full pagination
prompt regex would match instead (because it's listed higher up, it
would match first). But, once that "<return>" -notransfer -re
matches, it keeps re-matching forever. It seems like with
exp_continue, expect immediately retries matching, instead of first
reading in more data into the buffer, if available.
Fix this like I should have done in the first place. There's actually
no good reason for gdb_test_multiple to only match "<return>". We can
make gdb_test_multiple expect the whole pagination prompt text
instead, which is store in the 'pagination_prompt' global (similar to
'gdb_prompt'). Then a gdb_test_multiple caller that doesn't want the
default match to trigger, because it wants to see one pagination
prompt, does simply:
gdb_test_multiple "" $test {
-re "$pagination_prompt$" {
pass $test
}
}
which is just like when we don't want the default $gdb_prompt match
within gdb_test_multiple to trigger, like:
gdb_test_multiple "" $test {
-re "$gdb_prompt $" {
pass $test
}
}
Tested on x86_64 Fedora 20. In addition, I've let the racy tests run
all in parallel in a loop for 30 minutes, and they never failed.
gdb/testsuite/
2014-07-25 Pedro Alves <palves@redhat.com>
* gdb.base/double-prompt-target-event-error.exp
(cancel_pagination_in_target_event): Remove '-notransfer <return>'
match.
(cancel_pagination_in_target_event): Rework double prompt
detection.
* gdb.base/paginate-after-ctrl-c-running.exp
(test_ctrlc_while_target_running_paginates): Remove '-notransfer
<return>' match.
* gdb.base/paginate-bg-execution.exp
(test_bg_execution_pagination_return)
(test_bg_execution_pagination_cancel): Remove '-notransfer
<return>' matches.
* gdb.base/paginate-execution-startup.exp
(test_fg_execution_pagination_return)
(test_fg_execution_pagination_cancel): Remove '-notransfer
<return>' matches.
* gdb.base/paginate-inferior-exit.exp
(test_paginate_inferior_exited): Remove '-notransfer <return>'
match.
* lib/gdb-utils.exp (string_to_regexp): Move here from lib/gdb.exp.
* lib/gdb.exp (pagination_prompt): Run text through
string_to_regexp.
(gdb_test_multiple): Match $pagination_prompt instead of
"<return>".
(string_to_regexp): Move to lib/gdb-utils.exp.
This constifies deprecate_cmd and the "replacement" field in struct
cmd_list_element.
2014-07-24 Tom Tromey <tromey@redhat.com>
* cli/cli-decode.c (deprecate_cmd): Make "replacement" const.
* cli/cli-decode.h (struct cmd_list_element) <replacement>: Now
const.
* command.h (deprecate_cmd): Update.
* maint.c (maintenance_do_deprecate): Add casts.
This constifies a couple of functions in stack.c.
2014-07-24 Tom Tromey <tromey@redhat.com>
* stack.c (up_silently_base, down_silently_base): Make argument
const.
This constifies the "pattern" argument to solib_add.
2014-07-24 Tom Tromey <tromey@redhat.com>
* solib.c (solib_add): Make "pattern" const.
* solib.h (solib_add): Update.
This does some more constification in remote.c.
2014-07-24 Tom Tromey <tromey@redhat.com>
* remote.c (remote_serial_open, print_packet, putpkt)
(putpkt_binary): Constify.
* remote.h (putpkt): Update.
This constifies an argument to monitor_open.
2014-07-24 Tom Tromey <tromey@redhat.com>
* monitor.c (monitor_open): Make "args" const.
* monitor.h (monitor_open): Update.
This does a bit of constification in maint.c, making
print_bfd_section_info a bit cleaner in the process.
2014-07-24 Tom Tromey <tromey@redhat.com>
* maint.c (match_bfd_flags): Make "string" const.
(print_bfd_section_info): Remove casts.
(print_objfile_section_info): Make "string" const.
This constifies an argument to inf_child_open_target.
2014-07-24 Tom Tromey <tromey@redhat.com>
* inf-child.c (inf_child_open_target): Make "arg" const.
* inf-child.h (inf_child_open_target): Update.
This constifies an argument to unset_in_environ.
2014-07-24 Tom Tromey <tromey@redhat.com>
* environ.c (unset_in_environ): Make "var" const.
* environ.h (unset_in_environ): Update.
This does some minor constification in cli-dump.c.
2014-07-24 Tom Tromey <tromey@redhat.com>
* cli/cli-dump.c (scan_expression_with_cleanup): Return const.
Make "cmd" const.
(scan_filename_with_cleanup): Likewise.
(dump_memory_to_file, dump_value_to_file, restore_binary_file):
Make arguments const.
(restore_command): Update.
The TUI currently crashes when the user types <return> in response to
a pagination prompt:
$ gdb --tui ...
*the TUI is now active*
(gdb) set height 2
(gdb) help
List of classes of commands:
Program received signal SIGSEGV, Segmentation fault.
strlen () at ../sysdeps/x86_64/strlen.S:106
106 movdqu (%rax), %xmm12
(top-gdb) bt
#0 strlen () at ../sysdeps/x86_64/strlen.S:106
#1 0x000000000086be5f in xstrdup (s=0x0) at ../src/libiberty/xstrdup.c:33
#2 0x00000000005163f9 in tui_prep_terminal (notused1=1) at ../src/gdb/tui/tui-io.c:296
#3 0x000000000077a7ee in _rl_callback_newline () at ../src/readline/callback.c:82
#4 0x000000000077a853 in rl_callback_handler_install (prompt=0x0, linefunc=0x618b60 <command_line_handler>) at ../src/readline/callback.c:102
#5 0x0000000000718a5c in gdb_readline_wrapper_cleanup (arg=0xfd14d0) at ../src/gdb/top.c:788
#6 0x0000000000596d08 in do_my_cleanups (pmy_chain=0xcf0b38 <cleanup_chain>, old_chain=0x1043d10) at ../src/gdb/cleanups.c:155
#7 0x0000000000596d75 in do_cleanups (old_chain=0x1043d10) at ../src/gdb/cleanups.c:177
#8 0x0000000000718bd9 in gdb_readline_wrapper (prompt=0x7fffffffcfa0 "---Type <return> to continue, or q <return> to quit---")
at ../src/gdb/top.c:835
#9 0x000000000071cf74 in prompt_for_continue () at ../src/gdb/utils.c:1894
#10 0x000000000071d434 in fputs_maybe_filtered (linebuffer=0x1043db0 "List of classes of commands:\n\n", stream=0xf72e20, filter=1)
at ../src/gdb/utils.c:2111
#11 0x000000000071da0f in vfprintf_maybe_filtered (stream=0xf72e20, format=0x89aef8 "List of classes of %scommands:\n\n", args=0x7fffffffd118, filter=1)
at ../src/gdb/utils.c:2339
#12 0x000000000071da4a in vfprintf_filtered (stream=0xf72e20, format=0x89aef8 "List of classes of %scommands:\n\n", args=0x7fffffffd118)
at ../src/gdb/utils.c:2347
#13 0x000000000071dc72 in fprintf_filtered (stream=0xf72e20, format=0x89aef8 "List of classes of %scommands:\n\n") at ../src/gdb/utils.c:2399
#14 0x00000000004f90ab in help_list (list=0xe6d100, cmdtype=0x89ad8c "", class=all_classes, stream=0xf72e20)
at ../src/gdb/cli/cli-decode.c:1038
#15 0x00000000004f8dba in help_cmd (arg=0x0, stream=0xf72e20) at ../src/gdb/cli/cli-decode.c:946
Git 0017922 added:
@@ -776,6 +777,12 @@ gdb_readline_wrapper_cleanup (void *arg)
gdb_assert (input_handler == gdb_readline_wrapper_line);
input_handler = cleanup->handler_orig;
+
+ /* Reinstall INPUT_HANDLER in readline, without displaying a
+ prompt. */
+ if (async_command_editing_p)
+ rl_callback_handler_install (NULL, input_handler);
and tui_prep_terminal simply misses handling the case of a NULL
rl_prompt.
I also checked that readline's sources do similar checks.
gdb/
2014-07-24 Pedro Alves <palves@redhat.com>
* tui/tui-io.c (tui_prep_terminal): Handle NULL rl_prompt.
This patch removes some GDBSERVER checks from nat/linux-ptrace.c.
Currently the code uses a compile-time check to decide whether some
flags should be used. This changes the code to instead let users of
the module specify an additional set of flags; and then changes gdb's
linux-nat.c to call this function. At some later date, when the back
ends are fully merged, we will be able to remove this function again.
gdb/
2014-07-24 Tom Tromey <tromey@redhat.com>
Gary Benson <gbenson@redhat.com>
* nat/linux-ptrace.c (additional_flags): New global.
(linux_test_for_tracesysgood, linux_test_for_tracefork): Use
additional_flags; don't check GDBSERVER.
(linux_ptrace_set_additional_flags): New function.
* nat/linux-ptrace.h (linux_ptrace_set_additional_flags):
Declare.
* linux-nat.c (_initialize_linux_nat): Call
linux_ptrace_set_additional_flags.
gdbserver defines CORE_ADDR to be signed. This seems erroneous to
me; and furthermore likely to cause problems in common/, as it is
different from gdb's definition.
gdb/gdbserver/
2014-07-24 Tom Tromey <tromey@redhat.com>
Gary Benson <gbenson@redhat.com>
* server.h (CORE_ADDR): Now unsigned.
The target debug methods are inconsistently maintained. Most to_*
methods have some kind of targetdebug awareness, but not all of them
do. The ones that do vary in the quantity and quality of output they
generate.
This patch changes most of the target debug methods to be
automatically generated. All the arguments are printed, and separate
lines are printed for entering and existing the outermost call to the
target stack.
For example now you'd see:
-> multi-thread->to_terminal_ours (...)
-> multi-thread->to_is_async_p (...)
<- multi-thread->to_is_async_p (0x1ebb580) = 1
<- multi-thread->to_terminal_ours (0x1ebb580)
-> multi-thread->to_thread_address_space (...)
<- multi-thread->to_thread_address_space (0x1ebb580, 26802) = 1
In this case you can see nested calls. The "multi-thread" on the left
hand side is the topmost target's shortname.
There are some oddities with this patch. I'm on the fence about it
all, I really just wrote it on a whim.
It's not simple to convert every possible method, since a few don't
participate in target delegation.
Printing is done by type, so I introduced some new
debug-printing-specific typedefs to handle cases where it is nicer to
do something else.
On the plus side, this lays the groundwork for making targetdebug
affect every layer of the target stack. The idea would be to wrap
each target_ops in the stack with its own debug_target, and then you
could see calls propagate down the stack and back up; I suppose with
indentation to make it prettier. (That said there are some gotchas
lurking in this idea due to target stack introspection.)
Regtested on x86-64 Fedora 20.
2014-07-24 Tom Tromey <tromey@redhat.com>
* make-target-delegates (munge_type, write_debugmethod): New
functions.
(debug_names): New global.
($TARGET_DEBUG_PRINTER): New global.
(write_function_header): Strip TARGET_DEBUG_PRINTER from the type
name.
Write debug methods. Generate init_debug_target.
* target-debug.h: New file.
* target-delegates.c: Rebuild.
* target.c: Include target-debug.h.
(debug_target): Hoist definition.
(target_kill, target_get_section_table, target_memory_map)
(target_flash_erase, target_flash_done, target_detach)
(target_disconnect, target_wait, target_resume)
(target_pass_signals, target_program_signals, target_follow_fork)
(target_mourn_inferior, target_search_memory)
(target_thread_address_space, target_close)
(target_find_new_threads, target_core_of_thread)
(target_verify_memory, target_insert_mask_watchpoint)
(target_remove_mask_watchpoint): Remove targetdebug code.
(debug_to_post_attach, debug_to_prepare_to_store)
(debug_to_files_info, debug_to_insert_breakpoint)
(debug_to_remove_breakpoint, debug_to_can_use_hw_breakpoint)
(debug_to_region_ok_for_hw_watchpoint)
(debug_to_can_accel_watchpoint_condition)
(debug_to_stopped_by_watchpoint, debug_to_stopped_data_address)
(debug_to_watchpoint_addr_within_range)
(debug_to_insert_hw_breakpoint, debug_to_remove_hw_breakpoint)
(debug_to_insert_watchpoint, debug_to_remove_watchpoint)
(debug_to_terminal_init, debug_to_terminal_inferior)
(debug_to_terminal_ours_for_output, debug_to_terminal_ours)
(debug_to_terminal_save_ours, debug_to_terminal_info)
(debug_to_load, debug_to_post_startup_inferior)
(debug_to_insert_fork_catchpoint)
(debug_to_remove_fork_catchpoint)
(debug_to_insert_vfork_catchpoint)
(debug_to_remove_vfork_catchpoint)
(debug_to_insert_exec_catchpoint)
(debug_to_remove_exec_catchpoint, debug_to_has_exited)
(debug_to_can_run, debug_to_thread_architecture, debug_to_stop)
(debug_to_rcmd, debug_to_pid_to_exec_file): Remove.
(setup_target_debug): Call init_debug_target.
* target.h (TARGET_DEBUG_PRINTER): New macro.
(struct target_ops) <to_resume, to_wait, to_pass_signals,
to_program_signals>: Use TARGET_DEBUG_PRINTER.
GDB and gdbserver have functions named "fatal" that are used in
completely different ways. In gdbserver "fatal" is used to handle
critical errors: it differs from "error" in that "fatal" causes
gdbserver to exit whereas "error" does not. In GDB "fatal" is used
to abort the current operation and return to the command level.
This is implemented by throwing a non-error "RETURN_QUIT" exception.
This commit removes GDB's "fatal" and "vfatal" functions entirely.
The exception-throwing function "throw_vfatal" is renamed as
"throw_vquit", and a new convenience function "throw_quit" is added.
The small number of calls to "fatal" are replaced with calls to
"throw_quit", making what is happening more obvious.
This commit also modifies GDB's "throw_error" to call "throw_verror"
rather than calling "throw_it" directly. This change means the
assignment of RETURN_ERROR as the exception type now happens in
precisely one place in GDB rather than two.
gdb/
2014-07-24 Gary Benson <gbenson@redhat.com>
* exceptions.h (throw_vfatal): Renamed to...
(throw_vquit): New declaration.
(throw_quit): Likewise.
* exceptions.c (throw_vfatal): Renamed to...
(throw_vquit): New function.
(throw_quit): Likewise.
(throw_error): Call throw_verror rather than throw_it.
* utils.h (vfatal): Removed.
(fatal): Likewise.
* utils.c (vfatal): Removed.
(fatal): Likewise.
(internal_verror): Replaced call to fatal with call to throw_quit.
(quit): Replaced calls to fatal with calls to throw_quit.
microblaze_fetch instruction in order to use cache memory accesses
requested in target_read_code.
ChangeLog:
2014-06-17 Ajit Agarwal <ajitkum@xilinx.com>
* microblaze-tdep.c (microblaze_fetch_instruction): Use of
target_read_code.
also check whether less than zero -- for 'reg' is type 'int', and sizeof
(dwarf2_to_reg_map) is less than 0x7fff.
It is quoted in gdb_assert(), so need check 'reg' whether less than zero.
And the related warning (with '-W'):
../../binutils-gdb/gdb/microblaze-tdep.c:667:3: error: comparison between signed and unsigned integer expressions [-Werror=sign-compare]
ChangeLog:
* microblaze-tdep.c (microblaze_dwarf2_reg_to_regnum): Check whether
less tha zero in conditional expression.
This patch rewrites the make-target-delegates matching code a little
bit. The result is functionally the same (the output has some small
whitespace differences), but the new code is more forgiving regarding
the formatting of target.h. In particular now there's no need to
ensure that the return type and the method name appear on the same
line.
2014-07-23 Tom Tromey <tromey@redhat.com>
* make-target-delegates ($ARGS_PART): Match trailing close paren.
($INTRO_PART): Don't match whitespace.
($METHOD_TRAILER): Move earlier. Remove trailing semicolon and
argument matching.
($METHOD): Add $METHOD_TRAILER.
(trim): Rewrite.
(scan_target_h): New sub.
Change main loop not to collect state.
* target-delegates.c: Rebuild.
This commit fixes the build on systems without sigaltstack.
gdb/
2014-07-23 Gary Benson <gbenson@redhat.com>
* cp-support.c (gdb_demangle): Fix build on systems without
sigaltstack.
I cannot reproduce any wrong case having the code removed.
I just do not find it correct to have it disabled. But at the same time I do
like much / I do not find correct the code myself. It is a bit problematic to
have struct value describing a memory content which is no longer present
there.
What happens there:
------------------------------------------------------------------------------
volatile int vv;
static __attribute__((noinline)) int
bar (int &ref) {
ref = 20;
vv++; /* break-here */
return ref;
}
int main (void) {
int var = 10;
return bar (var);
}
------------------------------------------------------------------------------
<4><c7>: Abbrev Number: 13 (DW_TAG_GNU_call_site_parameter)
<c8> DW_AT_location : 1 byte block: 55 (DW_OP_reg5 (rdi))
<ca> DW_AT_GNU_call_site_value: 2 byte block: 91 74 (DW_OP_fbreg: -12)
<cd> DW_AT_GNU_call_site_data_value: 1 byte block: 3a (DW_OP_lit10)
------------------------------------------------------------------------------
gdb -ex 'b value_addr' -ex r --args ../gdb ./1 -ex 'watch vv' -ex r -ex 'p &ref@entry'
->
6 return ref;
bar (ref=@0x7fffffffd944: 20, ref@entry=@0x7fffffffd944: 10) at 1.C:25
------------------------------------------------------------------------------
At /* break-here */ struct value variable 'ref' is TYPE_CODE_REF.
With FSF GDB HEAD:
(gdb) x/gx arg1.contents
0x6004000a4ad0: 0x00007fffffffd944
(gdb) p ((struct value *)arg1.location.computed.closure).lval
$1 = lval_memory
(gdb) p/x ((struct value *)arg1.location.computed.closure).location.address
$3 = 0x7fffffffd944
With your #if0-ed code:
(gdb) x/gx arg1.contents
0x6004000a4ad0: 0x00007fffffffd944
(gdb) p ((struct value *)arg1.location.computed.closure).lval
$8 = not_lval
(gdb) p/x ((struct value *)arg1.location.computed.closure).location.address
$9 = 0x0
I do not see how to access
((struct value *)arg1.location.computed.closure).location.address
from GDB CLI. Trying
(gdb) p &ref@entry
will invoke value_addr()'s:
if (TYPE_CODE (type) == TYPE_CODE_REF)
/* Copy the value, but change the type from (T&) to (T*). We
keep the same location information, which is efficient, and
allows &(&X) to get the location containing the reference. */
and therefore the address gets fetched already from
arg1.contents
and not from
((struct value *)arg1.location.computed.closure).location.address
.
And for any other type than TYPE_CODE_REF this code you removed does not get
executed at all. This DW_AT_GNU_call_site_data_value DWARF was meant
primarily for Fortran but with -O0 entry values do not get produced
and with -Og and higher Fortran always optimizes out the passing by reference.
If you do not like the removed code there I am OK with removing it as I do not
know how to make it's use reproducible for user anyway. In the worst case
- if there really is some way how to exploit it - one should just get
Attempt to take address of value not located in memory.
instead of some wrong value and it may be easy to fix then.
gdb/
2014-07-22 Jan Kratochvil <jan.kratochvil@redhat.com>
* dwarf2loc.c (value_of_dwarf_reg_entry): Remove setting value address
for reference entry value target data value.
Message-ID: <20140720150727.GA18488@host2.jankratochvil.net>
The tests at
<https://sourceware.org/ml/gdb-patches/2014-07/msg00277.html> show
that comparing a fully optimized out value's contents with a value
that has not been optimized out, or is partially optimized out crashes
GDB:
(gdb) bt
#0 __memcmp_sse4_1 () at ../sysdeps/x86_64/multiarch/memcmp-sse4.S:816
#1 0x00000000005a1914 in memcmp_with_bit_offsets (ptr1=0x202b2f0 "\n", offset1_bits=0, ptr2=0x0, offset2_bits=0, length_bits=32)
at /home/pedro/gdb/mygit/build/../src/gdb/value.c:678
#2 0x00000000005a1a05 in value_available_contents_bits_eq (val1=0x2361ad0, offset1=0, val2=0x23683b0, offset2=0, length=32)
at /home/pedro/gdb/mygit/build/../src/gdb/value.c:717
#3 0x00000000005a1c09 in value_available_contents_eq (val1=0x2361ad0, offset1=0, val2=0x23683b0, offset2=0, length=4)
at /home/pedro/gdb/mygit/build/../src/gdb/value.c:769
#4 0x00000000006033ed in read_frame_arg (sym=0x1b78d20, frame=0x19bca50, argp=0x7fff4aba82b0, entryargp=0x7fff4aba82d0)
at /home/pedro/gdb/mygit/build/../src/gdb/stack.c:416
#5 0x0000000000603abb in print_frame_args (func=0x1b78cb0, frame=0x19bca50, num=-1, stream=0x1aea450) at /home/pedro/gdb/mygit/build/../src/gdb/stack.c:671
#6 0x0000000000604ae8 in print_frame (frame=0x19bca50, print_level=0, print_what=SRC_AND_LOC, print_args=1, sal=...)
at /home/pedro/gdb/mygit/build/../src/gdb/stack.c:1205
#7 0x0000000000604050 in print_frame_info (frame=0x19bca50, print_level=0, print_what=SRC_AND_LOC, print_args=1, set_current_sal=1)
at /home/pedro/gdb/mygit/build/../src/gdb/stack.c:857
#8 0x00000000006029b3 in print_stack_frame (frame=0x19bca50, print_level=0, print_what=SRC_AND_LOC, set_current_sal=1)
at /home/pedro/gdb/mygit/build/../src/gdb/stack.c:169
#9 0x00000000005fc4b8 in print_stop_event (ws=0x7fff4aba8790) at /home/pedro/gdb/mygit/build/../src/gdb/infrun.c:6068
#10 0x00000000005fc830 in normal_stop () at /home/pedro/gdb/mygit/build/../src/gdb/infrun.c:6214
The 'ptr2=0x0' in frame #1 is val2->contents, and since git 4f14910f:
gdb/ChangeLog
2013-11-26 Andrew Burgess <aburgess@broadcom.com>
* value.c (allocate_optimized_out_value): Mark value as non-lazy.
... a fully optimized-out value can have it's value contents buffer
NULL.
As a spotgap fix, revert 4f14910f, with a comment. A full fix would
be too invasive for 7.8.
gdb/
2014-07-22 Pedro Alves <palves@redhat.com>
* value.c (allocate_optimized_out_value): Don't mark value as
non-lazy.
TERNOP_SLICE was added for language Chill, but it is used for Ada and D later.
Since language Chill was removed from GDB, TERNOP_SLICE is only used for
Ada and D. This patch is to update its comments.
gdb:
2014-07-20 Yao Qi <yao@codesourcery.com>
* std-operator.def: Update comments to TERNOP_SLICE.
BINOP_RANGE was added by the following commit for chill language.
commit badefd2800
Author: Per Bothner <per@bothner.com>
Date: Wed Nov 29 22:59:31 1995 +0000
* expression.h (enum exp_opcode): Add BINOP_RANGE.
* expprint.c (dump_expression): Support BINOP_RANGE.
* eval.c (evaluate_subexp_standard): Handle BINOP_RANGE (as error).
(case MULTI_SUBSCRIPT): Fix broken f77 value->int ad hoc conversion.
* ch-lang.c (chill_op_print_tab): Support BINOP_RANGE.
(evaluate_subexp_chill): Error on BINOP_COMMA.
Chill language is no longer supported, so we can remove BINOP_RANGE too.
This patch is to remove BINOP_RANGE.
gdb:
2014-07-20 Yao Qi <yao@codesourcery.com>
* std-operator.def: Remove BINOP_RANGE.
* breakpoint.c (watchpoint_exp_is_const): Update.
* expprint.c (dump_subexp_body_standard): Likewise.
* eval.c (init_array_element): Remove dead code.
(evaluate_subexp_standard): Likewise.
Chill language support was removed several years ago, and BINOP_IN
isn't used for Pascal. This patch is to remove BINOP_IN.
gdb:
2014-07-20 Yao Qi <yao@codesourcery.com>
* std-operator.def: Remove BINOP_IN.
* breakpoint.c (watchpoint_exp_is_const): Update.
* eval.c (evaluate_subexp_standard): Likewise.
* expprint.c (dump_subexp_body_standard): Likewise.
Prior to version MicroBlaze v8.10.a,EDK 13.1, XMD's gdbserver stub returned 57
registers in response to GDB's G request. Starting with version MicroBlaze
v8.10.a, EDK 13.1, XMD added the slr and shr register, for a count of 59
registers. This patch adds these registers to the expected G response. This patch
fixes the above problem for baremetal and also supports the backward compatibility.
ChangeLog:
2014-07-02 Ajit Agarwal <ajitkum@xilinx.com>
* microblaze-tdep.c (microblaze_register_names): Add
the rshr and rslr register names.
(microblaze_gdbarch_init): Use of tdesc_has_registers.
Use of tdesc_find_feature. Use of tdesc_data_alloc.
Use of tdesc_numbered_register. Use of
microblaze_register_g_packet_guesses. Use of
tdesc_use_registers. Use of set_gdbarch_register_type.
(microblaze_register_g_packet_guesses): New.
* microblaze-tdep.h (microblaze_reg_num): Add
field MICROBLAZE_SLR_REGNUM MICROBLAZE_SHR_REGNUM
MICROBLAZE_NUM_REGS and MICROBLAZE_NUM_CORE_REGS.
(microblaze_frame_cache): Use of MICROBLAZE_NUM_REGS.
* features/microblaze-core.xml: New file.
* features/microblaze-stack-protect.xml: New file.
* features/microblaze-with-stack-protect.c: New file.
* features/microblaze-with-stack-protect.xml: New file.
* features/microblaze.xml: New file.
* features/microblaze.c: New file.
* features/Makefile (microblaze-with-stack-protect): Add
microblaze-with-stack-protect microblaze and
microblaze-expedite.
* regformats/microblaze-with-stack-protect.dat: New file.
* regformats/microblaze.dat: New file.
* doc/gdb.texinfo (MicroBlaze Features): New.
Signed-off-by:Ajit Agarwal ajitkum@xilinx.com
While working on some target stack changes, I noticed that exec_ops is
only used from exec.c. This patch makes it "static". This is cleaner
and makes it simpler to reason about the use of the target.
Tested by rebuilding.
I'm checking this in as obvious.
2014-07-18 Tom Tromey <tromey@redhat.com>
* exec.c (exec_ops): Now static.
* exec.h (exec_ops): Don't declare.
A long time ago Pedro pointed out that there are some calls to
find_target_beneath that pass in an explicit target_ops; but which
should instead use the ops provided to the method in question. See:
https://sourceware.org/ml/gdb-patches/2014-01/msg00429.html
This patch is just a minor cleanup to fix all such calls. There were
only three.
2014-07-18 Tom Tromey <tromey@redhat.com>
* spu-multiarch.c (spu_region_ok_for_hw_watchpoint): Pass "self"
to find_target_beneath.
* ravenscar-thread.c (ravenscar_prepare_to_store): Pass "ops" to
find_target_beneath.
(ravenscar_mourn_inferior): Pass "self" to find_target_beneath.
This fixes PR gdb/17130.
The bug is that some code in utils.c was not updated during the target
delegation change:
if (job_control
/* If there is no terminal switching for this target, then we can't
possibly get screwed by the lack of job control. */
|| current_target.to_terminal_ours == NULL)
fatal ("Quit");
else
fatal ("Quit (expect signal SIGINT when the program is resumed)");
After the delegation change, to_terminal_ours will never be NULL.
I think this bug can be seen before the target delegation change by
enabling target debugging -- this would also cause to_terminal_ours to
be non-NULL.
The fix is to introduce a new target_supports_terminal_ours function,
that properly checks the target stack. This is not perhaps ideal, but
I think is a reasonable-enough approach, and in keeping with some
other existing code of the same form.
This patch also fixes a similar bug in target_supports_delete_record.
2014-07-18 Tom Tromey <tromey@redhat.com>
PR gdb/17130:
* utils.c (quit): Use target_supports_terminal_ours.
* target.h (target_supports_terminal_ours): Declare.
* target.c (target_supports_delete_record): Don't check
to_delete_record against NULL.
(target_supports_terminal_ours): New function.
This patch cleans up some minor inconsistencies in target delegation.
It's primary purpose is to avoid confusion in the code. A few spots
were checking the "beneath" target; however this can only be NULL for
the dummy target, so such tests are not needed. Some other spots were
iterating over the beneath targets, looking for a method
implementation. This is not needed for methods handled by
make-target-delegates, as there is always an implementation.
2014-07-18 Tom Tromey <tromey@redhat.com>
PR gdb/17130:
* spu-multiarch.c (spu_region_ok_for_hw_watchpoint)
(spu_fetch_registers, spu_store_registers, spu_xfer_partial)
(spu_search_memory, spu_mourn_inferior): Simplify delegation.
* linux-thread-db.c (thread_db_pid_to_str): Always delegate.
* windows-nat.c (windows_xfer_partial): Always delegate.
* record-btrace.c (record_btrace_xfer_partial): Simplify
delegation.
(record_btrace_fetch_registers, record_btrace_store_registers)
(record_btrace_prepare_to_store, record_btrace_resume)
(record_btrace_wait, record_btrace_find_new_threads)
(record_btrace_thread_alive): Likewise.
* procfs.c (procfs_xfer_partial): Always delegate.
* corelow.c (core_xfer_partial): Always delegate.
* sol-thread.c (sol_find_new_threads): Simplify delegation.
This patch moves exec_make_note_section a bit earlier in exec.c. This
lets us remove an otherwise unnecessary forward declaration and it
also makes the file a bit more in line with other code, as now
_initialize_exec is the final function in the file.
Tested by rebuilding.
I'm committing this as obvious.
2014-07-18 Tom Tromey <tromey@redhat.com>
* exec.c (exec_make_note_section): Move earlier.
Since we use tkill everywhere, using kill to try to kill each lwp
individually looks suspiciously odd. We should really be using tgkill
everywhere, but at least while we don't get there this makes us
consistent.
gdb/gdbserver/
2014-07-16 Pedro Alves <palves@redhat.com>
* linux-low.c (linux_kill_one_lwp): Use kill_lwp, not kill.
gdb/
2014-07-16 Pedro Alves <palves@redhat.com>
* linux-nat.c (kill_callback): Use kill_lwp, not kill.
