Disable the Traceback Table generation on PowerPC for this test. The
Traceback Table consists of a series of bit fields to indicate things like
the Traceback Table version, language, and specific information about the
function. The Traceback Table is generated following the end of the code
for every function by default. The Traceback Table is defined in the
PowerPC ELF ABI and is intended to support debuggers and exception
handlers. The Traceback Table is displayed in the disassembly of functions
by default and is part of the function length. The table is typically
interpreted by the disassembler as data represented by .long xxx entries.
Generation of the Traceback Table is disabled in this test using the
PowerPC specific gcc compiler option -mtraceback=no, the xlc option
additional_flags-qtable=none and the clang optons
-mllvm -xcoff-traceback-table=false. Disabling the Traceback Table
generation in this test results in the gdb_test_multiple statement
correctly locating the address of the bclr instruction before the statement
"End of assembler dump." in the disassembly output.
When building gdb with -fsanitize-threads and running test-case
gdb.ada/char_enum_unicode.exp, I run into:
...
WARNING: ThreadSanitizer: data race (pid=21301)^M
Write of size 8 at 0x7b2000008080 by main thread:^M
#0 free <null> (libtsan.so.2+0x4c5e2)^M
#1 _dl_close_worker <null> (ld-linux-x86-64.so.2+0x4b7b)^M
#2 convert_between_encodings() charset.c:584^M
...
#21 cooked_index_functions::expand_symtabs_matching() read.c:18606
...
This is fixed by making cooked_index_functions::expand_symtabs_matching wait
for the cooked index finalization to be done.
Tested on x86_64-linux.
https://sourceware.org/bugzilla/show_bug.cgi?id=29311https://sourceware.org/bugzilla/show_bug.cgi?id=29286
Add a sequential_for_each alongside the parallel_for_each, which can be used
as a drop-in replacement.
This can be useful when debugging multi-threading behaviour, and you want to
limit multi-threading in a fine-grained way.
Tested on x86_64-linux, by using it instead of the parallel_for_each in
dwarf2_build_psymtabs_hard.
When building gdb with gcc 4.8.5, we run into:
...
In file included from /usr/include/c++/4.8/future:43:0,
from gdbsupport/thread-pool.h:30,
from gdb/dwarf2/cooked-index.h:33,
from gdb/dwarf2/read.h:26,
from gdb/dwarf2/abbrev-cache.c:21:
/usr/include/c++/4.8/atomic: In instantiation of \
‘_Tp std::atomic<_Tp>::load(std::memory_order) const [with _Tp = \
packed<dwarf_unit_type, 1ul>; std::memory_order = std::memory_order]’:
gdb/dwarf2/read.h:332:44: required from here
/usr/include/c++/4.8/atomic:208:13: error: no matching function for call to \
‘packed<dwarf_unit_type, 1ul>::packed()’
_Tp tmp;
^
...
Fix this by adding the default constructor for packed.
Tested on x86_64-linux, with gdb build with gcc 4.8.5.
When building gdb with -fsanitize=thread and running test-case
gdb.dwarf2/inlined_subroutine-inheritance.exp, we run into a data race
between:
...
Read of size 1 at 0x7b2000003010 by thread T4:
#0 packed<language, 1ul>::operator language() const packed.h:54
#1 dwarf2_per_cu_data::set_lang(language) read.h:363
...
and:
...
Previous write of size 1 at 0x7b2000003010 by main thread:
#0 dwarf2_per_cu_data::set_lang(language) read.h:365
...
Fix this by making per_cu->m_lang atomic.
Tested on x86_64-linux.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29286
With gdb with -fsanitize=thread and test-case gdb.ada/array_bounds.exp, I run
into a data race between:
...
Read of size 1 at 0x7b2000025f0f by main thread:
#0 packed<dwarf_unit_type, 1ul>::operator dwarf_unit_type() const packed.h:54
#1 dwarf2_per_cu_data::set_unit_type(dwarf_unit_type) read.h:339
...
and:
...
Previous write of size 1 at 0x7b2000025f0f by thread T3:
#0 dwarf2_per_cu_data::set_unit_type(dwarf_unit_type) read.h:341
...
Fix this by making per_cu->unit_type atomic.
Tested on x86_64-linux.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29286
When doing:
...
$ gdb ./outputs/gdb.ada/char_enum_unicode/foo -batch -ex "break foo.adb:26"
...
with a gdb build with -fsanitize=thread I run into a data race:
...
WARNING: ThreadSanitizer: data race (pid=30917)
Write of size 8 at 0x7b0400004070 by main thread:
#0 free <null> (libtsan.so.2+0x4c5e2)
#1 xfree<char> gdbsupport/gdb-xfree.h:37 (gdb+0x650f17)
#2 charset_vector::clear() gdb/charset.c:703 (gdb+0x651354)
#3 charset_vector::~charset_vector() gdb/charset.c:697 (gdb+0x6512d3)
#4 <null> <null> (libtsan.so.2+0x32643)
#5 captured_main_1 gdb/main.c:1310 (gdb+0xa3975a)
...
The problem is that we're freeing the charset_vector elements in the destructor,
which may still be used by a worker thread.
Fix this by not freeing the charset_vector elements in the destructor.
Tested on x86_64-linux.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29311
I meant to make this change before committing, to let compilers know
the code on the false branch of md_parse_name is dead.
* config/tc-ppc.c (ppc_parse_name): Return void.
* config/tc-ppc.h (md_parse_name): Always true.
(ppc_parse_name): Update prototype.
Allows register names to appear in symbol assignments, so for example
tocp = %r2
mr %r3,tocp
now assembles.
* gas/config/tc-ppc.c (REG_NAME_CNT): Delete, replace uses with
ARRAY_SIZE.
(register_name): Rename to..
(md_operand): ..this. Only handle %reg.
(cr_names): Rename to..
(cr_cond): ..this. Just keep conditions.
(ppc_parse_name): Add mode param. Search both cr_cond and
pre_defined_registers. Handle absolute and register symbol
values here rather than in expr.c:operand().
(md_assemble): Don't special case register name matching in
operands, except to set cr_operand as appropriate.
* gas/config/tc-ppc.h (md_operand): Don't define.
(md_parse_name, ppc_parse_name): Update.
* read.c (pseudo_set): Copy over entire O_register value.
* testsuite/gas/ppc/regsyms.d.
* testsuite/gas/ppc/regsyms.s: New test.
* testsuite/gas/ppc/ppc.exp: Run it.
A WIP version of a patch
(https://sourceware.org/pipermail/gdb-patches/2022-June/190202.html)
resulted in a bug that went unnoticed by the testuite, like so:
(gdb) PASS: gdb.threads/no-unwaited-for-left.exp: enable scheduler-locking, for main thread
continue
Continuing.
[New Thread 1251861.1251861]
No unwaited-for children left.
(gdb) PASS: gdb.threads/no-unwaited-for-left.exp: continue stops when the main thread exits
info threads
Id Target Id Frame
3 Thread 1251861.1251863 "no-unwaited-for" __pthread_clockjoin_ex (threadid=140737351558976, thread_return=0x0, clockid=<optimized out>, abstime=<optimized out>, block=<optimized out>) at pthread_join_common.c:145
4 Thread 1251861.1251861 "no-unwaited-for" <unavailable> in ?? ()
The current thread <Thread ID 1> has terminated. See `help thread'.
(gdb) PASS: gdb.threads/no-unwaited-for-left.exp: only thread 3 left, main thread terminated
Somehow, above, GDB re-added the zombie leader back before printing
"No unwaited-for children left.". The "only thread 3 left, main
thread terminated" test should have caught this, but didn't. That is
because the test's regexp has a ".*" after the part that matches
thread 3. This commit tightens that regexp to catch such a bug. It
also tightens the "only main thread left, thread 2 terminated" test's
regexp in the same way.
Change-Id: I8744f327a0aa0e2669d1ddda88247e99b91cefff
On PowePC, the test fails on a compile error:
/../binutils-gdb-current/gdb/testsuite/gdb.base/stap-probe.c:107:1: error: expected '=', ',', ';', 'asm' or 'attribute' before 'use_xmm_reg'
107 | use_xmm_reg (int val)
| ^~~~~~~~~~~
Where the source code for stap-probe.c is:
static const char * __attribute__((noinline)) ATTRIBUTE_NOCLONE
use_xmm_reg (int val) <-- line 107
{
...
The issue is the ATTRIBUTE_NOCLONE is not defined as an attribute as
expected. The #define for ATTRIBUTE_NOCLONE can be found in
../lib/attributes.h.
This patch adds the missing include statement for the definition of
ATTRIBUTE_NOCLONE.
The patch has been tested and verified on a Power10 system.
This patch adds the needed define ASM_REG for PowerPC.
The patch was run on a Power 10 system. The gdb Summary for the run lists
2 expected passes, no unexpected failures or untested testcases.
Please let me know if this patch is acceptable for mainline.
Carl Love
Due to recent changes in the default value of -fcf-protection for gcc, the
test gdb.base/step-indirect-call-thunk.exp fails on Intel X86-64 with the
error:
Executing on host: gcc -fno-stack-protector -fdiagnostics-color=never
-mindirect-branch=thunk -mfunction-return=thunk -c -g
-o /.../gdb/testsuite/outputs/gdb.base/step-indirect-call-thunk/step-indirect-call-thunk0.o
/.../gdb/testsuite/gdb.base/step-indirect-call-thunk.c
(timeout = 300) builtin_spawn -ignore SIGHUP gcc -fno-stack-protector
-fdiagnostics-color=never -mindirect-branch=thunk -mfunction-return=thunk -c
-g -o /.../gdb/testsuite/outputs/gdb.base/step-indirect-call-thunk/step-indirect-call-thunk0.o
/.../binutils-gdb-current/gdb/testsuite/gdb.base/step-indirect-call-thunk.c
/.../gdb/testsuite/gdb.base/step-indirect-call-thunk.c:
In function 'inc': /.../gdb/testsuite/gdb.base/step-indirect-call-thunk.c:
22:1: error: '-mindirect-branch' and '-fcf-protection' are not compatible
22 | { /* inc.1 */
As stated in the error message the default "-fcf-protection" and
"-mindirect-branch' are in compatible. The fcf-protection argument needs
to be "-fcf-protection=none" for the test to compile on Intel.
The gcc command line "-mindirect-branch' is an Intel specific and will give
an error on other platforms. A check for X86 is added so the test will
only run on X86 platforms.
The patch has been tested and verified on Power 10 and Intel X86-64 systems
with no regressions.
With a test like this:
1 #include <dlfcn.h>
2 int
3 main ()
4 {
5 dlsym (RTLD_DEFAULT, "FOO");
6 return 0;
7 }
and then "start" followed by "until 6", GDB currently incorrectly
stops inside the runtime loader, instead of line 6. Vis:
...
Temporary breakpoint 1, main () at until.c:5
4 {
(gdb) until 6
0x00007ffff7f0a90d in __GI__dl_catch_exception (exception=exception@entry=0x7fffffffdb00, operate=<optimized out>, args=0x7ffff7f0a90d <__GI__dl_catch_exception+109>) at dl-error-skeleton.c:206
206 dl-error-skeleton.c: No such file or directory.
(gdb)
The problem is related to longjmp handling -- dlsym internally
longjmps on error. The testcase can be reduced to this:
1 #include <setjmp.h>
2 void func () {
3 jmp_buf buf;
4 if (setjmp (buf) == 0)
5 longjmp (buf, 1);
6 }
7
8 int main () {
9 func ();
10 return 0; /* until to here */
11 }
and then with "start" followed by "until 10", GDB currently
incorrectly stops at line 4 (returning from setjmp), instead of line
10.
The problem is that the BPSTAT_WHAT_CLEAR_LONGJMP_RESUME code in
infrun.c fails to find the initiating frame, and so infrun thinks that
the longjmp jumped somewhere outer to "until"'s originating frame.
Here:
case BPSTAT_WHAT_CLEAR_LONGJMP_RESUME:
{
struct frame_info *init_frame;
/* There are several cases to consider.
1. The initiating frame no longer exists. In this case we
must stop, because the exception or longjmp has gone too
far.
...
init_frame = frame_find_by_id (ecs->event_thread->initiating_frame);
if (init_frame) // this is NULL!
{
...
}
/* For Cases 1 and 2, remove the step-resume breakpoint, if it
exists. */
delete_step_resume_breakpoint (ecs->event_thread);
end_stepping_range (ecs); // case 1., so we stop.
}
The initiating frame is set by until_break_command ->
set_longjmp_breakpoint. The initiating frame is supposed to be the
frame that is selected when the command was issued, but
until_break_command instead passes the frame id of the _caller_ frame
by mistake. When the "until LINE" command is issued from main, the
caller frame is the caller of main. When later infrun tries to find
that frame by id, it fails to find it, because frame_find_by_id
doesn't unwind past main.
The bug is that we passed the caller frame's id to
set_longjmp_breakpoint. We should have passed the selected frame's id
instead.
Change-Id: Iaae1af7cdddf296b7c5af82c3b5b7d9b66755b1c
When building with clang 15, I got this error:
CXX server.o
server.cc:2985:10: error: variable 'new_argc' set but not used [-Werror,-Wunused-but-set-variable]
int i, new_argc;
^
Remove the unused variable to eliminate the error.
Tested by rebuilding on x86_64-linux with clang 15.
We have in per_cu->set_lang this comment:
...
void set_lang (enum language lang)
{
/* We'd like to be more strict here, similar to what is done in
set_unit_type, but currently a partial unit can go from unknown to
minimal to ada to c. */
...
Fix this by not setting m_lang for partial units.
This requires us to move the m_unit_type initialization to ensure that
m_unit_type is initialized before per_cu->m_lang.
Tested on x86_64-linux, with native and target board cc-with-dwz-m.
This improves the "set scheduler-locking" documentation in the GDB
manual:
- Use a table to describe the four available modes.
- Describe "step" in terms of "on" and "off".
- Tweak the "replay" mode's description to describe replay first
instead of recording, and also mention how the mode behaves during
normal execution.
- Say what is the default mode.
Change-Id: Ie12140138b37534b7fc1d904da34f0f174aa11ce
The cu->per_cu->lang field was added to carry information from the initial
partial symtabs phase to the symtab expansion phase, for the benefit of a
particular optimization in process_imported_unit_die.
Other uses have been added, but since the first phase now has been
parallelized, those have become problematic and sources of race conditions.
Fix this by adding dwarf2_cu::lang () and using it where we can to replace
cu->per_cu->lang () with cu->lang ().
Also assert in dwarf2_cu::lang () that we're not returning language_unknown.
Tested on x86_64-linux.
When building gdb with -fsanitize=address we run into:
...
builtin_spawn gdb -nw -nx -iex set height 0 -iex set width 0 -data-directory \
build/gdb/data-directory^M
==10637==ASan runtime does not come first in initial library list; you \
should either link runtime to your application or manually preload it with \
LD_PRELOAD.^M
ERROR: GDB process no longer exists
...
Prevent the ASan runtime error by using
ASAN_OPTIONS=verify_asan_link_order=0. This makes both test-cases pass.
Tested on x86_64-linux.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29358
Add a new file tsan-suppressions.txt, to suppress the "unlock unlocked mutex"
problem in ncurses, filed in PR29328.
The file is added to the TSAN_OPTIONS in lib/gdb.exp.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29328
When building gdb with gcc 4.8.5, we run into problems due to unconditionally
using:
...
gdb_static_assert (std::is_trivially_copyable<packed>::value);
...
in gdbsupport/packed.h.
Fix this by guarding the usage with HAVE_IS_TRIVIALLY_COPYABLE.
Tested by doing a full gdb build with gcc 4.8.5.
When building gdb with -fsanitize=thread and gcc 12, and running test-case
gdb.dwarf2/dwz.exp, we run into a data race between:
...
Read of size 1 at 0x7b200000300d by thread T2:^M
#0 cutu_reader::cutu_reader(dwarf2_per_cu_data*, dwarf2_per_objfile*, \
abbrev_table*, dwarf2_cu*, bool, abbrev_cache*) gdb/dwarf2/read.c:6164 \
(gdb+0x82ec95)^M
...
and:
...
Previous write of size 1 at 0x7b200000300d by main thread:^M
#0 prepare_one_comp_unit gdb/dwarf2/read.c:23588 (gdb+0x86f973)^M
...
In other words, between:
...
if (this_cu->reading_dwo_directly)
...
and:
...
cu->per_cu->lang = pretend_language;
...
Likewise, we run into a data race between:
...
Write of size 1 at 0x7b200000300e by thread T4:
#0 process_psymtab_comp_unit gdb/dwarf2/read.c:6789 (gdb+0x830720)
...
and:
...
Previous read of size 1 at 0x7b200000300e by main thread:
#0 cutu_reader::cutu_reader(dwarf2_per_cu_data*, dwarf2_per_objfile*, \
abbrev_table*, dwarf2_cu*, bool, abbrev_cache*) gdb/dwarf2/read.c:6164 \
(gdb+0x82edab)
...
In other words, between:
...
this_cu->unit_type = DW_UT_partial;
...
and:
...
if (this_cu->reading_dwo_directly)
...
Likewise for the write to addresses_seen in cooked_indexer::check_bounds and a
read from is_dwz in dwarf2_find_containing_comp_unit for test-case
gdb.dwarf2/dw2-dir-file-name.exp and target board cc-with-dwz-m.
The problem is that the written fields are part of the same memory location as
the read fields, so executing a read and write in different threads is
undefined behavour.
Making the written fields separate memory locations, using the new
struct packed template fixes this.
The set of fields has been established experimentally to be the
minimal set to get rid of this type of -fsanitize=thread errors, but
more fields might require the same treatment.
Looking at the properties of the lang field, unlike dwarf_version it's
not available in the unit header, so it will be set the first time
during the parallel cooked index reading. The same holds for
unit_type, and likewise for addresses_seen.
dwarf2_per_cu_data::addresses_seen is moved so that the bitfields that
currently follow it can be merged in the same memory location as the
bitfields that currently precede it, for better packing.
Tested on x86_64-linux.
Co-Authored-By: Pedro Alves <pedro@palves.net>
Change-Id: Ifa94f0a2cebfae5e8f6ddc73265f05e7fd9e1532
When building gdb with -fsanitize=thread and gcc 12, and running test-case
gdb.dwarf2/dwz.exp, we run into a few data races. For example, between:
...
Write of size 1 at 0x7b200000300e by thread T4:
#0 process_psymtab_comp_unit gdb/dwarf2/read.c:6789 (gdb+0x830720)
...
and:
...
Previous read of size 1 at 0x7b200000300e by main thread:
#0 cutu_reader::cutu_reader(dwarf2_per_cu_data*, dwarf2_per_objfile*, \
abbrev_table*, dwarf2_cu*, bool, abbrev_cache*) gdb/dwarf2/read.c:6164 \
(gdb+0x82edab)
...
In other words, between:
...
this_cu->unit_type = DW_UT_partial;
...
and:
...
if (this_cu->reading_dwo_directly)
...
The problem is that the written fields are part of the same memory
location as the read fields, so executing a read and write in
different threads is undefined behavour.
Making the written fields separate memory locations, like this:
...
struct {
ENUM_BITFIELD (dwarf_unit_type) unit_type : 8;
};
...
fixes it, however that also increases the size of struct
dwarf2_per_cu_data, because it introduces padding due to alignment of
these new structs, which align on the natural alignment of the
specified type of their fields. We can fix that with
__attribute__((packed)), like so:
struct {
ENUM_BITFIELD (dwarf_unit_type) unit_type : 8 __attribute__((packed));
};
but to avoid having to write that in several places and add suitable
comments explaining how that concoction works, introduce a new struct
packed template that wraps/hides this. Instead of the above, we'll be
able to write:
packed<dwarf_unit_type, 1> unit_type;
Note that we can't change the type of dwarf_unit_type, as that is
defined in include/, and shared with other projects, some of those
written in C.
This patch just adds the struct packed type. Following patches will
make use of it. One of those patches will want to wrap a struct
packed in an std::atomic, like:
std::atomic<std::packed<language, 1>> m_lang;
so the new gdbsupport/packed.h header adds some operators to make
comparisions between that std::atomic and the type that the wrapped
struct packed wraps work, like in:
if (m_lang == language_c)
It would be possible to implement struct packed without using
__attribute__((packed)), by having it store an array of bytes of the
appropriate size instead, however that would make it less convenient
to debug GDB. The way it's implemented, printing a struct packed
variable just prints its field using its natural type, which is
particularly useful if the type is an enum. I believe that
__attribute__((packed)) is supported by all compilers that are able to
build GDB. Even a few BFD headers use on ATTRIBUTE_PACKED on external
types:
include/coff/external.h: } ATTRIBUTE_PACKED
include/coff/external.h:} ATTRIBUTE_PACKED ;
include/coff/external.h:} ATTRIBUTE_PACKED ;
include/coff/pe.h:} ATTRIBUTE_PACKED ;
include/coff/pe.h:} ATTRIBUTE_PACKED;
include/elf/external.h:} ATTRIBUTE_PACKED Elf_External_Versym;
It is not possible to build GDB with MSVC today, but if it could, that
would be one compiler that doesn't support this attribute. However,
it supports packing via pragmas, so there's a way to cross that bridge
if we ever get to it. I believe any compiler worth its salt supports
some way of packing.
In any case, the worse that happens without the attribute is that some
types become larger than ideal. Regardless, I've added a couple
static assertions to catch such compilers in action:
/* Ensure size and aligment are what we expect. */
gdb_static_assert (sizeof (packed) == Bytes);
gdb_static_assert (alignof (packed) == 1);
Change-Id: Ifa94f0a2cebfae5e8f6ddc73265f05e7fd9e1532
It might be possible to hit md_end before md_begin is called, don't
segfault if so. Also, remove a useless check.
* gas/config/tc-ppc.c (insn_calloc): Remove needless overflow
check.
(ppc_md_end): Check ppc_hash before deleting. Clear ppc_hash.
The bug testcase uses an output section named .rel or .rela which has
input .data sections mapped to it. The input .data section has
relocations. When counting output relocations SHT_REL and SHT_RELA
section reloc_count is ignored, with the justification that reloc
sections themselves can't have relocations and some backends use
reloc_count in reloc sections. However, the test wrongly used the
output section type (which normally would match input section type).
Fix that. Note that it is arguably wrong for ld to leave the output
.rel/.rela section type as SHT_REL/SHT_RELA when non-empty non-reloc
sections are written to it, but I'm not going to change that since it
might be useful to hand-craft relocs in a data section that is then
written to a SHT_REL/SHT_RELA output section.
PR 29355
* elflink.c (bfd_elf_final_link): Use input section type rather
than output section type to determine whether to exclude using
reloc_count from that section.
For csky arch, the correspondence between Dwarf registers and GDB
registers are as follows:
dwarf regnos 0~31 ==> gdb regs r0~r31
dwarf regno CSKY_HI_REGNUM(36) ==> gdb reg hi
dwarf regno CSKY_LO_REGNUM(37) ==> gdb reg hi
dwarf regno CSKY_PC_REGNUM(72) ==> gdb reg pc
dwarf regnos FV_PSEUDO_REGNO_FIRST(74)~FV_PSEUDO_REGNO_LAST(201)
==>
gdb regs s0~s127 (pseudo regs for float and vector regs)
other dwarf regnos have no corresponding gdb regs to them.
[Note: the testcased added by this commit depends on
https://sourceware.org/pipermail/gdb-patches/2022-June/190259.html,
otherwise GDB just crashes when detaching the core]
Currently, in MI, =thread-created are always emitted, like:
=thread-group-started,id="i1",pid="195680"
=thread-created,id="1",group-id="i1"
...
but on teardown, if the target uses exit_inferior_silent, then you'll
only see the inferior exit notification (thread-group-exited), no
notification for threads.
The core target is one of the few targets that use
exit_inferior_silent. Here's an example session:
-target-select core $corefile
=thread-group-started,id="i1",pid="195680"
=thread-created,id="1",group-id="i1"
...
^connected,frame=....
(gdb)
-target-detach
=thread-group-exited,id="i1"
^done
(gdb)
This imbalance of emitting =thread-created but then not =thread-exited
seems off to me. (And, it complicates changes I want to do to
centralize emitting thread exit notifications for the CLI, which is
why I'm looking at this.)
And then, since most other targets use exit_inferior instead of
exit_inferior_silent, MI is already emitting =thread-exited
notifications when tearing down an inferior, for most targets.
This commit makes MI always emit the =thread-exited notifications,
even for exit_inferior_silent.
Afterwards, when debugging a core, MI outputs:
(gdb)
-target-detach
=thread-exited,id="1",group-id="i1" << new line
=thread-group-exited,id="i1"
^done
(gdb)
Surprisingly, there's no MI testcase debugging a core file. This
commit adds the first.
Change-Id: I5100501a46f07b6bbad3e04d120c2562a51c93a4
After loading a core file, you're supposed to be able to use "detach"
to unload the core file. That unfortunately regressed starting with
GDB 11, with these commits:
1192f124a3 - gdb: generalize commit_resume, avoid commit-resuming when threads have pending statuses
408f66864a - detach in all-stop with threads running
resulting in a GDB crash:
...
Thread 1 "gdb" received signal SIGSEGV, Segmentation fault.
0x0000555555e842bf in maybe_set_commit_resumed_all_targets () at ../../src/gdb/infrun.c:2899
2899 if (proc_target->commit_resumed_state)
(top-gdb) bt
#0 0x0000555555e842bf in maybe_set_commit_resumed_all_targets () at ../../src/gdb/infrun.c:2899
#1 0x0000555555e848bf in scoped_disable_commit_resumed::reset (this=0x7fffffffd440) at ../../src/gdb/infrun.c:3023
#2 0x0000555555e84a0c in scoped_disable_commit_resumed::reset_and_commit (this=0x7fffffffd440) at ../../src/gdb/infrun.c:3049
#3 0x0000555555e739cd in detach_command (args=0x0, from_tty=1) at ../../src/gdb/infcmd.c:2791
#4 0x0000555555c0ba46 in do_simple_func (args=0x0, from_tty=1, c=0x55555662a600) at ../../src/gdb/cli/cli-decode.c:95
#5 0x0000555555c112b0 in cmd_func (cmd=0x55555662a600, args=0x0, from_tty=1) at ../../src/gdb/cli/cli-decode.c:2514
#6 0x0000555556173b1f in execute_command (p=0x5555565c5916 "", from_tty=1) at ../../src/gdb/top.c:699
The code that crashes looks like:
static void
maybe_set_commit_resumed_all_targets ()
{
scoped_restore_current_thread restore_thread;
for (inferior *inf : all_non_exited_inferiors ())
{
process_stratum_target *proc_target = inf->process_target ();
if (proc_target->commit_resumed_state)
^^^^^^^^^^^
With 'proc_target' above being null. all_non_exited_inferiors filters
out inferiors that have pid==0. We get here at the end of
detach_command, after core_target::detach has already run, at which
point the inferior _should_ have pid==0 and no process target. It is
clear it no longer has a process target, but, it still has a pid!=0
somehow.
The reason the inferior still has pid!=0, is that core_target::detach
just unpushes, and relies on core_target::close to actually do the
getting rid of the core and exiting the inferior. The problem with
that is that detach_command grabs an extra strong reference to the
process stratum target, so the unpush_target inside
core_target::detach doesn't actually result in a call to
core_target::close.
Fix this my moving the cleaning up the core inferior to a shared
routine called by both core_target::close and core_target::detach. We
still need to cleanup the inferior from within core_file::close
because there are paths to it that want to get rid of the core without
going through detach. E.g., "core-file" -> "run".
This commit includes a new test added to gdb.base/corefile.exp to
cover the "core-file core" -> "detach" scenario.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29275
Change-Id: Ic42bdd03182166b19f598428b0dbc2ce6f67c893
In the description of stop replies, where the "thread" register is
explained, and where the fork and vfork stop reasons are detailed,
there are references to "@var{thread-id}", but such variable does not
actually exist. This commit fixes it.
Change-Id: If679944aaf15f6f64aabe506339a9e7667864cab
The -msign-return-address switch has been dropped from GCC, but some
older compiler may still support it. Make sure we try both
-msign-return-address and -mbranch-protection before bailing out when
running gdb.arch/aarch64-pauth.exp.
This commit extends GDB to make use of libopcodes styling support
where available, currently this is just i386 based architectures, and
RISC-V.
For architectures that don't support styling using libopcodes GDB will
fall back to using the Python Pygments package, when the package is
available.
The new libopcodes based styling has the disassembler identify parts
of the disassembled instruction, e.g. registers, immediates,
mnemonics, etc, and can style these components differently.
Additionally, as the styling is now done in GDB we can add settings to
allow the user to configure which colours are used right from the GDB
CLI.
There's some new maintenance commands:
maintenance set libopcodes-styling enabled on|off
maintenance show libopcodes-styling
These can be used to manually disable use of libopcodes styling. This
is a maintenance command as it's not anticipated that a user should
need to do this. But, this could be useful for testing, or, in some
rare cases, a user might want to override the Python hook used for
disassembler styling, and then disable libopcode styling so that GDB
falls back to using Python. Right now I would consider this second
use case a rare situation, which is why I think a maintenance command
is appropriate.
When libopcodes is being used for styling then the user can make use
of the following new styles:
set/show style disassembler comment
set/show style disassembler immediate
set/show style disassembler mnemonic
set/show style disassembler register
The disassembler also makes use of the 'address' and 'function'
styles to style some parts of the disassembler output. I have also
added the following aliases though:
set/show style disassembler address
set/show style disassembler symbol
these are aliases for:
set/show style address
set/show style function
respectively, and exist to make it easier for users to discover
disassembler related style settings. The 'address' style is used to
style numeric addresses in the disassembler output, while the 'symbol'
or 'function' style is used to style the names of symbols in
disassembler output.
As not every architecture supports libopcodes styling, the maintenance
setting 'libopcodes-styling enabled' has an "auto-off" type behaviour.
Consider this GDB session:
(gdb) show architecture
The target architecture is set to "auto" (currently "i386:x86-64").
(gdb) maintenance show libopcodes-styling enabled
Use of libopcodes styling support is "on".
the setting defaults to "on" for architectures that support libopcodes
based styling.
(gdb) set architecture sparc
The target architecture is set to "sparc".
(gdb) maintenance show libopcodes-styling enabled
Use of libopcodes styling support is "off" (not supported on architecture "sparc")
the setting will show as "off" if the user switches to an architecture
that doesn't support libopcodes styling. The underlying setting is
still "on" at this point though, if the user switches back to
i386:x86-64 then the setting would go back to being "on".
(gdb) maintenance set libopcodes-styling enabled off
(gdb) maintenance show libopcodes-styling enabled
Use of libopcodes styling support is "off".
now the setting is "off" for everyone, even if the user switches back
to i386:x86-64 the setting will still show as "off".
(gdb) maintenance set libopcodes-styling enabled on
Use of libopcodes styling not supported on architecture "sparc".
(gdb) maintenance show libopcodes-styling enabled
Use of libopcodes styling support is "off".
attempting to switch the setting "on" for an unsupported architecture
will give an error, and the setting will remain "off".
(gdb) set architecture auto
The target architecture is set to "auto" (currently "i386:x86-64").
(gdb) maintenance show libopcodes-styling enabled
Use of libopcodes styling support is "off".
(gdb) maintenance set libopcodes-styling enabled on
(gdb) maintenance show libopcodes-styling enabled
Use of libopcodes styling support is "on".
the user will need to switch back to a supported architecture before
they can one again turn this setting "on".
The gdb_disassemble_info class is a wrapper around the libopcodes
disassemble_info struct. The 'stream' field of disassemble_info is
passed as an argument to the fprintf_func and fprintf_styled_func
callbacks when the disassembler wants to print anything.
Previously, GDB would store a pointer to a ui_file object in the
'stream' field, then, when the disassembler wanted to print anything,
the content would be written to the ui_file object. An example of an
fprintf_func callback, from gdb/disasm.c is:
int
gdb_disassembler::dis_asm_fprintf (void *stream, const char *format, ...)
{
/* Write output to STREAM here. */
}
This is fine, but has one limitation, within the print callbacks we
only have access to STREAM, we can't access any additional state
stored within the gdb_disassemble_info object.
Right now this isn't a problem, but in a future commit this will
become an issue, how we style the output being written to STREAM will
depend on the state of the gdb_disassemble_info object, and this state
might need to be updated, depending on what is being printed.
In this commit I propose changing the 'stream' field of the
disassemble_info to carry a pointer to the gdb_disassemble_info
sub-class, rather than the stream itself.
We then have the two sub-classes of gdb_disassemble_info to consider,
the gdb_non_printing_disassembler class never cared about the stream,
previously, for this class, the stream was nullptr. With the change
to make stream be a gdb_disassemble_info pointer, no further updates
are needed for gdb_non_printing_disassembler.
The other sub-class is gdb_printing_disassembler. In this case the
sub-class now carries around a pointer to the stream object. The
print callbacks are updated to cast the incoming stream object back to
a gdb_printing_disassembler, and then extract the stream.
This is purely a refactoring commit. A later commit will add
additional state to the gdb_printing_disassembler, and update the
print callbacks to access this state.
There should be no user visible changes after this commit.
With gdb build with -fsanitize=thread and test-case
gdb.dwarf2/dw4-sig-types.exp and target board cc-with-dwz-m we run into a data
race between:
...
Write of size 4 at 0x7b2800002268 by thread T4:^M
#0 cutu_reader::cutu_reader(dwarf2_per_cu_data*, dwarf2_per_objfile*, \
abbrev_table*, dwarf2_cu*, bool, abbrev_cache*) gdb/dwarf2/read.c:6236 \
(gdb+0x82f525)^M
...
and this read:
...
Previous read of size 4 at 0x7b2800002268 by thread T1:^M
#0 dwarf2_find_containing_comp_unit gdb/dwarf2/read.c:23444 \
(gdb+0x86e22e)^M
...
In other words, between this write:
...
this_cu->length = cu->header.get_length ();
...
and this read:
...
&& mid_cu->sect_off + mid_cu->length > sect_off))
...
of per_cu->length.
Fix this similar to the per_cu->dwarf_version case, by only setting it if
needed, and otherwise verifying that the same value is used. [ Note that the
same code is already present in the other cutu_reader constructor. ]
Move this logic into into a member function set_length to make sure it's used
consistenly, and make the field private in order to enforce access through the
member functions, and rename it to m_length.
This exposes (running test-case gdb.dwarf2/fission-reread.exp) that in
fill_in_sig_entry_from_dwo_entry, the m_length field is overwritten.
For now, allow for that exception.
While we're at it, make sure that the length is set before read.
Tested on x86_64-linux.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29344
There's a spot in read_comp_units_from_section where we explictly use
initial_length_size to get the total length:
...
this_cu->length = cu_header.length + cu_header.initial_length_size;
...
Instead, just use cu_header.get_length ().
Tested on x86_64-linux.
Commit 736918239b ("gdb: LoongArch: add orig_a0 into register set")
introduced orig_a0, similar processing needs to be done in gdbserver.
At the same time, add orig_a0 related comments.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Move "enum loongarch_regnum" to gdb/arch/loongarch.h so that the
macro definitions can be used in gdbserver/linux-loongarch-low.cc
to simplify the code.
Signed-off-by: Youling Tang <tangyouling@loongson.cn>
Signed-off-by: Tiezhu Yang <yangtiezhu@loongson.cn>
Cleaning up the subsym_hash memory is a real pain. Keys and values
entered into the table are quite diverse. In some cases the key is
allocated and thus needs to be freed, in others the key is a const
string. Values are similar, and in some cases not even a string.
Tidy this by inserting a new subsym_ent_t that describes key/value
type. This meant the math_hash table was no longer needed. The patch
also tidies how math functions are called, those that are supposed to
return int now no longer return their value in a float.
* config/tc-tic54x.c (math_hash): Delete.
(subsym_proc_entry): Move earlier, make proc a union, merge with..
(math_proc_entry): ..this. Delete type.
(math_procs): Merge into subsym_procs.
(subsym_ent_t): New. Use this type in subsym_hash..
(stag_add_field_symbols, tic54x_var, tic54x_macro_info): ..here..
(md_begin, subsym_create_or_replace, subsym_lookup): ..and here..
(subsym_substitute): ..and here. Adjust subsym_proc_entry
function calls. Free replacement when not returned.
(subsym_get_arg): Adjust subsym_lookup.
(free_subsym_ent, subsym_htab_create ): New functions, use when
creating subsym_hash.
(free_local_label_ent, local_label_htab_create): Similarly.
(tic54x_remove_local_label): Delete.
(tic54x_clear_local_labels): Simplify.
(tic54x_asg): Use notes obstack to dup strings.
(tic54x_eval): Likewise.
(subsym_ismember): Likewise.
(math_cvi, math_int, math_sgn): Return int.
(tic54x_macro_start): Decrement macro_level before calling as_fatal.
(tic54x_md_end): New function.
* config/tc-tic54h.c (tic54x_md_end): Declare.
(md_end): Define.
