While experimenting with JIT reader API I realized that calling repr ()
on objfile created by JIT reader crashes GDB.
The problem was that objfpy_repr () called objfile_filename () which
returned NULL, causing PyString_FromFormat () to crash.
This commit fixes this problem by using objfile_name () instead of
objfile_filename (). This also makes consistent with the value of gdb.Objfile.filename variable.
The last updates of MIG introduced qualifying strings and arrays with
const as appropriate. We thus have to update the protypes in gdb too.
Change-Id: I3f72aac1dfa6e58d1394d5776b822d7c8f2409df
VER_FLG_WEAK doesn't indicate that all symbol references of the symbol
version have STB_WEAK. VER_FLG_WEAK indicates a weak symbol version
definition with no symbols associated with it. It is used to verify
the existence of a particular implementation without any symbol references
to the weak symbol version.
PR ld/24718
* testsuite/ld-elf/pr24718-1.d: New file.
* testsuite/ld-elf/pr24718-1.s: Likewise.
* testsuite/ld-elf/pr24718-1.t: Likewise.
Don't load debug sections if we aren't dumping any debug sections.
PR binutils/28843
* objdump.c (dump_any_debugging): New.
(load_debug_section): Return false if dump_any_debugging isn't
set.
(main): Set dump_any_debugging when dumping any debug sections.
* readelf (dump_any_debugging): New.
(parse_args): Set dump_any_debugging when dumping any debug
sections.
(load_debug_section): Return false if dump_any_debugging isn't
set.
I have warnings like these showing in my editor all the time, so I
thought I'd run clang-tidy with this diagnostic on all the files (that I
can compile) and fix them.
There is still one warning, in utils.c, but that's because some code
is mixed up with preprocessor macros (#ifdef TUI), so I think there no
good solution there.
Change-Id: I345175fc7dd865318f0fbe61ac026c88c3b6a96b
Info symbol is expected to print the symbol table name of a symbol, since
symbol lookup happens via the minimal symbol table. This name
corresponds to the linkage name in the full symbol table.
For gfortran (and maybe others) these names currently have the form
XXXX.NUMBER where XXXX is the symbol name and NUMBER a compiler
generated appendix for mangling.
An example taken from the modified nested-funcs-2.exp would be
~~~~
$ objdump -t ./outputs/gdb.fortran/nested-funcs-2/nested-funcs-2 | grep \
increment
00000000000014ab l F .text 0000000000000095 increment.3883
000000000000141c l F .text 000000000000008f increment_program_global.3881
~~~~
This mangled name gets recognized by the Ada demangler/decoder and decoded as
Ada to XXXX (setting the symbol language to Ada). This leads to output
of XXXX over XXXX.NUMBER for info symbol on gfortran symbols.
For ifort and ifx the generated linkage names have the form
SCOPEA_SCOPEB_XXXX_ which are not recognized by the Ada decoder (or any
other demangler for that matter) and thus printed as is.
The respective objdump in the above case looks like
~~~~
$ objdump -t ./outputs/gdb.fortran/nested-funcs-2/nested-funcs-2 | grep \
increment
0000000000403a44 l F .text 0000000000000074 contains_keyword_IP_increment_
0000000000403ab8 l F .text 0000000000000070
contains_keyword_IP_increment_program_global_
~~~~
In the unmodified testcase this results in 'fails' when ran with the intel
compilers:
~~~~
>> make check RUNTESTFLAGS="gdb.fortran/nested-funcs-2.exp \
GDBFLAGS='$GDBFLAGS' CC_FOR_TARGET='icpc' F90_FOR_TARGET='ifort'"
...
=== gdb Summary ===
\# of expected passes 80
\# of unexpected failures 14
~~~~
Note that there is no Fortran mangling standard. We keep the gfortran
behavior as is and modify the test to reflect ifx and ifort mangled
names which fixes above fails.
Signed-off-by: Nils-Christian Kempke <nils-christian.kempke@intel.com>
PR 98886
PR 99935
* rust-demangle.c (struct rust_demangler): Add a recursion
counter.
(demangle_path): Increment/decrement the recursion counter upon
entry and exit. Fail if the counter exceeds a fixed limit.
(demangle_type): Likewise.
(rust_demangle_callback): Initialise the recursion counter,
disabling if requested by the option flags.
In trying to find a testcase for PR28827, I managed to hit a linker
error in bfd_set_section_contents with a .branch_lt input section
being too large for the output .branch_lt.
bfd/
PR 28827
* elf64-ppc.c (ppc64_elf_size_stubs): Set section size to
maxsize past STUB_SHRINK_ITER before laying out. Remove now
unnecessary conditional setting of maxsize at start of loop.
ld/
* testsuite/ld-powerpc/pr28827-2.d,
* testsuite/ld-powerpc/pr28827-2.lnk,
* testsuite/ld-powerpc/pr28827-2.s: New test.
* testsuite/ld-powerpc/powerpc.exp: Run it.
i386-fbsd-tdep.c and amd64-fbsd-tdep.c failed to build on my x86-64
Fedora 34 machine, using the system gcc, after a recent patch. These
two files now have unused variables, which provokes a warning in this
configuration.
I'm checking in this patch to remove the unused variables.
The previous patch wasn't quite correct. The size and padding depends
on offset used in the current iteration, and if we're fudging the
offset past STUB_SHRINK_ITER then we'd better use that offset. We
can't have plt_stub_pad using stub_sec->size as the offset.
PR 28827
* elf64-ppc.c (plt_stub_pad): Add stub_off param.
(ppc_size_one_stub): Set up stub_offset to value used in this
iteration before sizing the stub. Adjust plt_stub_pad calls.
From: Peilin Ye <peilin.ye@bytedance.com>
objcopy's --only-keep-debug option has been broken for ELF files since
commit 8c803a2dd7.
1. binutils/objcopy.c:setup_section() marks non-debug sections as
SHT_NOBITS, then calls bfd_copy_private_section_data();
2. If ISEC and OSEC share the same section flags,
bfd/elf.c:_bfd_elf_init_private_section_data() restores OSEC's
section type back to ISEC's section type, effectively undoing
"make_nobits".
* objcopy.c (setup_section): Act on make_nobits after calling
bfd_copy_private_section_data.
The previous code triggered the following error on an i386 host:
/git/gdb/gdb/ppc-sysv-tdep.c:1764:34: error: non-constant-expression cannot be narrowed from type 'ULONGEST' (aka 'unsigned long long') to 'size_t' (aka 'unsigned int') in initializer list [-Wc++11-narrowing]
unscaled.read ({writebuf, TYPE_LENGTH (valtype)},
^~~~~~~~~~~~~~~~~~~~~
/git/gdb/gdb/gdbtypes.h:2043:31: note: expanded from macro 'TYPE_LENGTH'
^~~~~~~~~~~~~~~~~~
/git/gdb/gdb/ppc-sysv-tdep.c:1764:34: note: insert an explicit cast to silence this issue
unscaled.read ({writebuf, TYPE_LENGTH (valtype)},
^~~~~~~~~~~~~~~~~~~~~
static_cast<size_t>( )
/git/gdb/gdb/gdbtypes.h:2043:31: note: expanded from macro 'TYPE_LENGTH'
^~~~~~~~~~~~~~~~~~
1 error generated.
Fix this by using gdb::make_array_view.
Rather than using the x86-specific register offset tables, use
register maps to describe the layout of the general purpose registers
fetched via PT_GETREGS. The sole user-visible difference is that
FreeBSD/amd64 will now report additional segment registers ($ds, $es,
$fs, and $gs) for both 32-bit and 64-bit processes.
As part of these changes, the FreeBSD x86 native targets no longer use
amd64-bsd-nat.c or i386-bsd-nat.c. Remove FreeBSD-specific register
handling (for $fs_base, $gs_base, and XSAVE state) from these files.
Similarly, remove the global x86bsd_xsave_len from x86-bsd-nat.c. The
FreeBSD x86 native targets use a static xsave_len instead.
While here, rework the probing of PT_GETXMMREGS on FreeBSD/i386.
Probe the ptrace op once in the target read_description method and
cache the result for the future similar to the way the status of XSAVE
support is probed in the read_description method. In addition, return
the proper xcr0 mask (X87-only) for old kernels or systems without
either XSAVE or XMM support.
Use a register map to describe the registers in mcontext_t as part of
the signal frame as is done on several other FreeBSD arches. This
permits fetching the fsbase and gsbase register values from the signal
frame for both amd64 and i386 and permits fetching additional segment
registers stored as 16-bit values on amd64.
While signal frames on FreeBSD do contain floating point/XSAVE state,
these unwinders do not attempt to supply those registers. The
existing x86 signal frame uwinders do not support these registers, and
the only existing functions which handle FSAVE/FXSAVE/XSAVE state all
work with regcaches. In the future these unwinders could create a
tempory regcache, collect floating point registers, and then supply
values out of the regcache into the trad-frame.
In particular, this permits reporting the value of the $ds, $es, $fs,
and $gs segment registers from amd64 core dumps since they are stored
as 16-bit values rather than the 32-bit size assumed by i386_gregset.
When registers are supplied via regcache_supply_register from a
register block described by a register map, registers may be stored in
slots smaller than GDB's native register size (e.g. x86 segment
registers are 16 bits, but the GDB registers for those are 32-bits).
regcache_collect_regset is careful to zero-extend slots larger than a
register size, but regcache_supply_regset just used
regcache::raw_supply_part and did not initialize the upper bytes of a
register value.
trad_frame_set_reg_regmap assumes these semantics (zero-extending
short registers). Upcoming patches also require these semantics for
handling x86 segment register values stored in 16-bit slots on
FreeBSD. Note that architecturally x86 segment registers are 16 bits,
but the x86 gdb architectures treat these registers as 32 bits.
A few FreeBSD releases did not include the page holding the signal
code in core dumps. As a workaround, a sysctl was used to fetch the
default location of the signal code instead. The youngest affected
FreeBSD release is 10.1 released in November 2014 and EOLed in
December 2016. The fallback only works for native processes and would
require a separate unwinder once the FreeBSD arches are converted to
use tramp_frame for signal frames.
When building with clang, I run into an error:
...
tui/tui-disasm.c:138:25: error: moving a temporary object prevents copy
elision [-Werror,-Wpessimizing-move]
tal.addr_string = std::move (gdb_dis_out.release ());
^
tui/tui-disasm.c:138:25: note: remove std::move call here
tal.addr_string = std::move (gdb_dis_out.release ());
^~~~~~~~~~~ ~
...
The error above is caused by the recent commit 5d10a2041e ("gdb: add
string_file::release method").
Fix this by removing std::move.
Build on x86_64-linux with clang 13.0.0.
Add a .editorconfig [1] file. This helps configure editors
automatically with the right whitespace settings. It will help me,
since I need to juggle with different whitespace settings for different
projects. But I think it can also help newcomers get things right from
the start.
Some editors have native support for reading these files, while others
require a plug-in [2]. And if you don't want to use it, then this file
doesn't change anything to your life.
I added rules for the kinds of files I edit most often, but more can be
added later. I assumed that the rules were the same for GDB and the
other projects, but if that's not the case, we can always put
.editorconfig files in project subdirectories to override settings.
[1] https://editorconfig.org/
[2] https://editorconfig.org/#download
Change-Id: Ifda136d13877fafcf0d137fec8501f6a34e1367b
This is just a tidy, making the __ehdr_start symbol flag tweaks all in
one place.
* ldelf.c (ldelf_before_allocation): Don't set rel_from_abs
for __ehdr_start.
* ldlang.c (lang_symbol_tweaks): Set it here instead.
Using a symbol other than .TOC. with @tocbase is an extension to the
ABI. It is never valid to use a symbol without a definition in the
binary, and symbols on these expressions cannot be overridden. Make
this explicit by using ".hidden" in the testcase.
* testsuite/ld-powerpc/symtocbase-1.s: Align data. Make function
entry symbol hidden.
* testsuite/ld-powerpc/symtocbase-2.s: Likewise.
* testsuite/ld-powerpc/symtocbase.d: Adjust expected output.
The assertion is this one in ppc_build_one_stub
BFD_ASSERT (stub_entry->stub_offset >= stub_entry->group->stub_sec->size);
It is checking that a stub doesn't overwrite the tail of a previous
stub, so not something trivial.
Normally, stub sizing iterates until no stubs are added, detected by
no change in stub section size. Iteration also continues if no stubs
are added but one or more stubs increases in size, which also can be
detected by a change in stub section size. But there is a
pathological case where stub section sizing decreases one iteration
then increases the next. To handle that situation, stub sizing also
stops at more than STUB_SHRINK_ITER (20) iterations when calculated
stub section size is smaller. The previous larger size is kept for
the actual layout (so that building the stubs, which behaves like
another iteration of stub sizing, will see the stub section sizes
shrink). The problem with that stopping condition is that it assumes
that stub sizing is only affected by addresses external to the stub
sections, which isn't always true.
This patch fixes that by also keeping larger individual stub_offset
addresses past STUB_SHRINK_ITER. It also catches a further
pathological case where one stub shrinks and another expands in such a
way that no stub section size change is seen.
PR 28827
* elf64-ppc.c (struct ppc_link_hash_table): Add stub_changed.
(STUB_SHRINK_ITER): Move earlier in file.
(ppc_size_one_stub): Detect any change in stub_offset. Keep
larger one if past STUB_SHRINK_ITER.
(ppc64_elf_size_stubs): Iterate on stub_changed too.
g++ 11.1.0 has a bug where it will emit a negative
DW_AT_data_member_location in some cases:
$ cat test.cpp
#include <memory>
int
main()
{
std::unique_ptr<int> ptr;
}
$ g++ -g test.cpp
$ llvm-dwarfdump -F a.out
...
0x00000964: DW_TAG_member
DW_AT_name [DW_FORM_strp] ("_M_head_impl")
DW_AT_decl_file [DW_FORM_data1] ("/usr/include/c++/11.1.0/tuple")
DW_AT_decl_line [DW_FORM_data1] (125)
DW_AT_decl_column [DW_FORM_data1] (0x27)
DW_AT_type [DW_FORM_ref4] (0x0000067a "default_delete<int>")
DW_AT_data_member_location [DW_FORM_sdata] (-1)
...
This leads to a GDB crash (when built with ASan, otherwise probably
garbage results), since it tries to read just before (to the left, in
ASan speak) of the value's buffer:
==888645==ERROR: AddressSanitizer: heap-buffer-overflow on address 0x6020000c52af at pc 0x7f711b239f4b bp 0x7fff356bd470 sp 0x7fff356bcc18
READ of size 1 at 0x6020000c52af thread T0
#0 0x7f711b239f4a in __interceptor_memcpy /build/gcc/src/gcc/libsanitizer/sanitizer_common/sanitizer_common_interceptors.inc:827
#1 0x555c4977efa1 in value_contents_copy_raw /home/simark/src/binutils-gdb/gdb/value.c:1347
#2 0x555c497909cd in value_primitive_field(value*, long, int, type*) /home/simark/src/binutils-gdb/gdb/value.c:3126
#3 0x555c478f2eaa in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:333
#4 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
#5 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
#6 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
#7 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
#8 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
#9 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
#10 0x555c4760d45f in c_value_print_struct /home/simark/src/binutils-gdb/gdb/c-valprint.c:383
#11 0x555c4760df4c in c_value_print_inner(value*, ui_file*, int, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:438
#12 0x555c483ff9a7 in language_defn::value_print_inner(value*, ui_file*, int, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:632
#13 0x555c49758b68 in do_val_print /home/simark/src/binutils-gdb/gdb/valprint.c:1048
#14 0x555c49759b17 in common_val_print(value*, ui_file*, int, value_print_options const*, language_defn const*) /home/simark/src/binutils-gdb/gdb/valprint.c:1151
#15 0x555c478f2fcb in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:335
#16 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
#17 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
#18 0x555c4760d45f in c_value_print_struct /home/simark/src/binutils-gdb/gdb/c-valprint.c:383
#19 0x555c4760df4c in c_value_print_inner(value*, ui_file*, int, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:438
#20 0x555c483ff9a7 in language_defn::value_print_inner(value*, ui_file*, int, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:632
#21 0x555c49758b68 in do_val_print /home/simark/src/binutils-gdb/gdb/valprint.c:1048
#22 0x555c49759b17 in common_val_print(value*, ui_file*, int, value_print_options const*, language_defn const*) /home/simark/src/binutils-gdb/gdb/valprint.c:1151
#23 0x555c478f2fcb in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:335
#24 0x555c4760d45f in c_value_print_struct /home/simark/src/binutils-gdb/gdb/c-valprint.c:383
#25 0x555c4760df4c in c_value_print_inner(value*, ui_file*, int, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:438
#26 0x555c483ff9a7 in language_defn::value_print_inner(value*, ui_file*, int, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:632
#27 0x555c49758b68 in do_val_print /home/simark/src/binutils-gdb/gdb/valprint.c:1048
#28 0x555c49759b17 in common_val_print(value*, ui_file*, int, value_print_options const*, language_defn const*) /home/simark/src/binutils-gdb/gdb/valprint.c:1151
#29 0x555c4760f04c in c_value_print(value*, ui_file*, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:587
#30 0x555c483ff954 in language_defn::value_print(value*, ui_file*, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:614
#31 0x555c49759f61 in value_print(value*, ui_file*, value_print_options const*) /home/simark/src/binutils-gdb/gdb/valprint.c:1189
#32 0x555c48950f70 in print_formatted /home/simark/src/binutils-gdb/gdb/printcmd.c:337
#33 0x555c48958eda in print_value(value*, value_print_options const&) /home/simark/src/binutils-gdb/gdb/printcmd.c:1258
#34 0x555c48959891 in print_command_1 /home/simark/src/binutils-gdb/gdb/printcmd.c:1367
#35 0x555c4895a3df in print_command /home/simark/src/binutils-gdb/gdb/printcmd.c:1458
#36 0x555c4767f974 in do_simple_func /home/simark/src/binutils-gdb/gdb/cli/cli-decode.c:97
#37 0x555c47692e25 in cmd_func(cmd_list_element*, char const*, int) /home/simark/src/binutils-gdb/gdb/cli/cli-decode.c:2475
#38 0x555c4936107e in execute_command(char const*, int) /home/simark/src/binutils-gdb/gdb/top.c:670
#39 0x555c485f1bff in catch_command_errors /home/simark/src/binutils-gdb/gdb/main.c:523
#40 0x555c485f249c in execute_cmdargs /home/simark/src/binutils-gdb/gdb/main.c:618
#41 0x555c485f6677 in captured_main_1 /home/simark/src/binutils-gdb/gdb/main.c:1317
#42 0x555c485f6c83 in captured_main /home/simark/src/binutils-gdb/gdb/main.c:1338
#43 0x555c485f6d65 in gdb_main(captured_main_args*) /home/simark/src/binutils-gdb/gdb/main.c:1363
#44 0x555c46e41ba8 in main /home/simark/src/binutils-gdb/gdb/gdb.c:32
#45 0x7f71198bcb24 in __libc_start_main (/usr/lib/libc.so.6+0x27b24)
#46 0x555c46e4197d in _start (/home/simark/build/binutils-gdb-one-target/gdb/gdb+0x77f197d)
0x6020000c52af is located 1 bytes to the left of 8-byte region [0x6020000c52b0,0x6020000c52b8)
allocated by thread T0 here:
#0 0x7f711b2b7459 in __interceptor_calloc /build/gcc/src/gcc/libsanitizer/asan/asan_malloc_linux.cpp:154
#1 0x555c470acdc9 in xcalloc /home/simark/src/binutils-gdb/gdb/alloc.c:100
#2 0x555c49b775cd in xzalloc(unsigned long) /home/simark/src/binutils-gdb/gdbsupport/common-utils.cc:29
#3 0x555c4977bdeb in allocate_value_contents /home/simark/src/binutils-gdb/gdb/value.c:1029
#4 0x555c4977be25 in allocate_value(type*) /home/simark/src/binutils-gdb/gdb/value.c:1040
#5 0x555c4979030d in value_primitive_field(value*, long, int, type*) /home/simark/src/binutils-gdb/gdb/value.c:3092
#6 0x555c478f6280 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:501
#7 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
#8 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
#9 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
#10 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
#11 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
#12 0x555c4760d45f in c_value_print_struct /home/simark/src/binutils-gdb/gdb/c-valprint.c:383
#13 0x555c4760df4c in c_value_print_inner(value*, ui_file*, int, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:438
#14 0x555c483ff9a7 in language_defn::value_print_inner(value*, ui_file*, int, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:632
#15 0x555c49758b68 in do_val_print /home/simark/src/binutils-gdb/gdb/valprint.c:1048
#16 0x555c49759b17 in common_val_print(value*, ui_file*, int, value_print_options const*, language_defn const*) /home/simark/src/binutils-gdb/gdb/valprint.c:1151
#17 0x555c478f2fcb in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:335
#18 0x555c478f63b2 in cp_print_value /home/simark/src/binutils-gdb/gdb/cp-valprint.c:513
#19 0x555c478f02ca in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:161
#20 0x555c4760d45f in c_value_print_struct /home/simark/src/binutils-gdb/gdb/c-valprint.c:383
#21 0x555c4760df4c in c_value_print_inner(value*, ui_file*, int, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:438
#22 0x555c483ff9a7 in language_defn::value_print_inner(value*, ui_file*, int, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:632
#23 0x555c49758b68 in do_val_print /home/simark/src/binutils-gdb/gdb/valprint.c:1048
#24 0x555c49759b17 in common_val_print(value*, ui_file*, int, value_print_options const*, language_defn const*) /home/simark/src/binutils-gdb/gdb/valprint.c:1151
#25 0x555c478f2fcb in cp_print_value_fields(value*, ui_file*, int, value_print_options const*, type**, int) /home/simark/src/binutils-gdb/gdb/cp-valprint.c:335
#26 0x555c4760d45f in c_value_print_struct /home/simark/src/binutils-gdb/gdb/c-valprint.c:383
#27 0x555c4760df4c in c_value_print_inner(value*, ui_file*, int, value_print_options const*) /home/simark/src/binutils-gdb/gdb/c-valprint.c:438
#28 0x555c483ff9a7 in language_defn::value_print_inner(value*, ui_file*, int, value_print_options const*) const /home/simark/src/binutils-gdb/gdb/language.c:632
#29 0x555c49758b68 in do_val_print /home/simark/src/binutils-gdb/gdb/valprint.c:1048
Since there are some binaries with this in the wild, I think it would be
useful for GDB to work around this. I did the obvious simple thing, if
the DW_AT_data_member_location's value is -1, replace it with 0. I
added a producer check to only apply this fixup for GCC 11. The idea is
that if some other compiler ever uses a DW_AT_data_member_location value
of -1 by mistake, we don't know (before analyzing the bug at least) if
they did mean 0 or some other value. So I wouldn't want to apply the
fixup in that case.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=28063
Change-Id: Ieef3459b0b9bbce8bdad838ba83b4b64e7269d42
Fedora Rawhide is now using gcc-12.0. As part of updating to the
gcc-12.0 package set, Rawhide is also now using a version of libgcc_s
which lacks a .data section. This causes gdb to fail in the following
fashion while debugging a program (such as gdb) which uses libgcc_s:
(top-gdb) run
Starting program: rawhide-master/bld/gdb/gdb
...
objfiles.h:467: internal-error: sect_index_data not initialized
A problem internal to GDB has been detected,
further debugging may prove unreliable.
...
I snipped the backtrace from the above output. Instead, here's a
portion of a backtrace obtained using GDB's backtrace command.
(Obviously, in order to obtain it, I used a GDB which has been patched
with this commit.)
#0 internal_error (
file=0xc6a508 "gdb/objfiles.h", line=467,
fmt=0xc6a4e8 "sect_index_data not initialized")
at gdbsupport/errors.cc:51
#1 0x00000000005f9651 in objfile::data_section_offset (this=0x4fa48f0)
at gdb/objfiles.h:467
#2 0x000000000097c5f8 in relocate_address (address=0x17244, objfile=0x4fa48f0)
at gdb/stap-probe.c:1333
#3 0x000000000097c630 in stap_probe::get_relocated_address (this=0xa1a17a0,
objfile=0x4fa48f0)
at gdb/stap-probe.c:1341
#4 0x00000000004d7025 in create_exception_master_breakpoint_probe (
objfile=0x4fa48f0)
at gdb/breakpoint.c:3505
#5 0x00000000004d7426 in create_exception_master_breakpoint ()
at gdb/breakpoint.c:3575
#6 0x00000000004efcc1 in breakpoint_re_set ()
at gdb/breakpoint.c:13407
#7 0x0000000000956998 in solib_add (pattern=0x0, from_tty=0, readsyms=1)
at gdb/solib.c:1001
#8 0x00000000009576a8 in handle_solib_event ()
at gdb/solib.c:1269
...
The function 'relocate_address' in gdb/stap-probe.c attempts to do
its "relocation" by using objfile->data_section_offset(). That
method, data_section_offset() is defined as follows in objfiles.h:
CORE_ADDR data_section_offset () const
{
return section_offsets[SECT_OFF_DATA (this)];
}
The internal error occurs when the SECT_OFF_DATA macro finds that the
'sect_index_data' field is -1:
#define SECT_OFF_DATA(objfile) \
((objfile->sect_index_data == -1) \
? (internal_error (__FILE__, __LINE__, \
_("sect_index_data not initialized")), -1) \
: objfile->sect_index_data)
relocate_address() is obtaining the section offset in order to compute
a relocated address. For some ABIs, such as the System V ABI, the
section offsets will all be the same. So for those ABIs, it doesn't
matter which offset is used. However, other ABIs, such as the FDPIC
ABI, will have different offsets for the various sections. Thus, for
those ABIs, it is vital that this and other relocation code use the
correct offset.
In stap_probe::get_relocated_address, the address to which to add the
offset (thus forming the relocated address) is obtained via
this->get_address (); get_address is a getter for m_address in
probe.h. It's documented/defined as follows (also in probe.h):
/* The address where the probe is inserted, relative to
SECT_OFF_TEXT. */
CORE_ADDR m_address;
(Thanks to Tom Tromey for this observation.)
So, based on this, the current use of data_section_offset /
SECT_OFF_DATA is wrong. This relocation code should have been using
text_section_offset / SECT_OFF_TEXT all along. That being the
case, I've adjusted the stap-probe.c relocation code accordingly.
Searching the sources turned up one other use of data_section_offset,
in gdb/dtrace-probe.c, so I've updated that code as well. The same
reasoning presented above applies to this case too.
Summary:
* gdb/dtrace-probe.c (dtrace_probe::get_relocated_address):
Use method text_section_offset instead of data_section_offset.
* gdb/stap-probe.c (relocate_address): Likewise.
In remote_target::remote_btrace_maybe_reopen, we switch to the currently
iterated thread in order to set inferior_ptid for a subsequent xfer.
Move the switch_to_thread call directly before the target_read_stralloc
call to clarify why we need to switch threads.
The enable_btrace target method takes a ptid_t to identify the thread on
which tracing shall be enabled.
Change this to thread_info * to avoid translating back and forth between
the two. This will be used in a subsequent patch.
In remote_btrace_maybe_reopen() we iterate over threads and use
set_general_thread() to set the thread from which to transfer the btrace
configuration.
This sets the remote general thread but does not affect inferior_ptid. On
the xfer request later on, remote_target::xfer_partial() again sets the
remote general thread to inferior_ptid, overwriting what
remote_btrace_maybe_reopen() had done.
In one case, this led to inferior_ptid being null_ptid when we tried to
enable tracing on a newly created thread inside a newly created process
during attach.
This, in turn, led to find_inferior_pid() asserting when we iterated over
threads in record_btrace_is_replaying(), which was called from
record_btrace_target::xfer_partial() when reading the btrace configuration
of the new thread to check whether it was already being recorded.
The bug was exposed by
0618ae4149 gdb: optimize all_matching_threads_iterator
and found by
FAIL: gdb.btrace/enable-new-thread.exp: ... (GDB internal error)
Use switch_to_thread() in remote_btrace_maybe_reopen().
We use record_btrace_enable_warn() as the new-thread observer callback.
It is not used in other contexts.
Rename it to record_btrace_on_new_thread() to make its role more clear.
This commit adds support for source files that contain non utf-8
characters when performing source styling using the Python pygments
package. This does not change the behaviour of GDB when the GNU
Source Highlight library is used.
For the following problem description, assume that either GDB is built
without GNU Source Highlight support, of that this has been disabled
using 'maintenance set gnu-source-highlight enabled off'.
The initial problem reported was that a source file containing non
utf-8 characters would cause GDB to print a Python exception, and then
display the source without styling, e.g.:
Python Exception <class 'UnicodeDecodeError'>: 'utf-8' codec can't decode byte 0xc0 in position 142: invalid start byte
/* Source code here, without styling... */
Further, as the user steps through different source files, each time
the problematic source file was evicted from the source cache, and
then later reloaded, the exception would be printed again.
Finally, this problem is only present when using Python 3, this issue
is not present for Python 2.
What makes this especially frustrating is that GDB can clearly print
the source file contents, they're right there... If we disable
styling completely, or make use of the GNU Source Highlight library,
then everything is fine. So why is there an error when we try to
apply styling using Python?
The problem is the use of PyString_FromString (which is an alias for
PyUnicode_FromString in Python 3), this function converts a C string
into a either a Unicode object (Py3) or a str object (Py2). For
Python 2 there is no unicode encoding performed during this function
call, but for Python 3 the input is assumed to be a uft-8 encoding
string for the purpose of the conversion. And here of course, is the
problem, if the source file contains non utf-8 characters, then it
should not be treated as utf-8, but that's what we do, and that's why
we get an error.
My first thought when looking at this was to spot when the
PyString_FromString call failed with a UnicodeDecodeError and silently
ignore the error. This would mean that GDB would print the source
without styling, but would also avoid the annoying exception message.
However, I also make use of `pygmentize`, a command line wrapper
around the Python pygments module, which I use to apply syntax
highlighting in the output of `less`. And this command line wrapper
is quite happy to syntax highlight my source file that contains non
utf-8 characters, so it feels like the problem should be solvable.
It turns out that inside the pygments module there is already support
for guessing the encoding of the incoming file content, if the
incoming content is not already a Unicode string. This is what
happens for Python 2 where the incoming content is of `str` type.
We could try and make GDB smarter when it comes to converting C
strings into Python Unicode objects; this would probably require us to
just try a couple of different encoding schemes rather than just
giving up after utf-8.
However, I figure, why bother? The pygments module already does this
for us, and the colorize API is not part of the documented external
API of GDB. So, why not just change the colorize API, instead of the
content being a Unicode string (for Python 3), lets just make the
content be a bytes object. The pygments module can then take
responsibility for guessing the encoding.
So, currently, the colorize API receives a unicode object, and returns
a unicode object. I propose that the colorize API receive a bytes
object, and return a bytes object.
This removes the global wrap_here function, so that future calls
cannot be introduced. Instead, all callers must use the method on the
appropriate ui_file.
This temporarily moves the implementation of this method to utils.c.
This will change once the remaining patches to untangle the pager have
been written.
Right now, wrap_here is a global function. In the long run, we'd like
output streams to be relatively self-contained objects, and having a
global function like this is counter to that goal. Also, existing
code freely mixes writes to some parameterized stream with calls to
wrap_here -- but wrap_here only really affects gdb_stdout, so this is
also incoherent.
This step is a patch toward making wrap_here more sane. It adds a
wrap_here method to ui_file and changes ui_out implementations to use
it.
I think it only really makes sense to call wrap_here with an argument
consisting solely of spaces. Given this, it seemed better to me that
the argument be an int, rather than a string. This patch is the
result. Much of it was written by a script.
This commit attempts to improve the help text that is generated for
gdb.Parameter objects when the user fails to provide their own
documentation.
Documentation for a gdb.Parameter is currently pulled from two
sources: the class documentation string, and the set_doc/show_doc
class attributes. Thus, a fully documented parameter might look like
this:
class Param_All (gdb.Parameter):
"""This is the class documentation string."""
show_doc = "Show the state of this parameter"
set_doc = "Set the state of this parameter"
def get_set_string (self):
val = "on"
if (self.value == False):
val = "off"
return "Test Parameter has been set to " + val
def __init__ (self, name):
super (Param_All, self).__init__ (name, gdb.COMMAND_DATA, gdb.PARAM_BOOLEAN)
self._value = True
Param_All ('param-all')
Then in GDB we see this:
(gdb) help set param-all
Set the state of this parameter
This is the class documentation string.
Which is fine. But, if the user skips both of the documentation parts
like this:
class Param_None (gdb.Parameter):
def get_set_string (self):
val = "on"
if (self.value == False):
val = "off"
return "Test Parameter has been set to " + val
def __init__ (self, name):
super (Param_None, self).__init__ (name, gdb.COMMAND_DATA, gdb.PARAM_BOOLEAN)
self._value = True
Param_None ('param-none')
Now in GDB we see this:
(gdb) help set param-none
This command is not documented.
This command is not documented.
That's not great, the duplicated text looks a bit weird. If we drop
different parts we get different results. Here's what we get if the
user drops the set_doc and show_doc attributes:
(gdb) help set param-doc
This command is not documented.
This is the class documentation string.
That kind of sucks, we say it's undocumented, then proceed to print
the documentation. Finally, if we drop the class documentation but
keep the set_doc and show_doc:
(gdb) help set param-set-show
Set the state of this parameter
This command is not documented.
That seems OK.
So, I think there's room for improvement.
With this patch, for the four cases above we now see this:
# All values provided by the user, no change in this case:
(gdb) help set param-all
Set the state of this parameter
This is the class documentation string.
# Nothing provided by the user, the first string is now different:
(gdb) help set param-none
Set the current value of 'param-none'.
This command is not documented.
# Only the class documentation is provided, the first string is
# changed as in the previous case:
(gdb) help set param-doc
Set the current value of 'param-doc'.
This is the class documentation string.
# Only the set_doc and show_doc are provided, this case is unchanged
# from before the patch:
(gdb) help set param-set-show
Set the state of this parameter
This command is not documented.
The one place where this change might be considered a negative is when
dealing with prefix commands. If we create a prefix command but don't
supply the set_doc / show_doc strings, then this is what we saw before
my patch:
(gdb) python Param_None ('print param-none')
(gdb) help set print
set print, set pr, set p
Generic command for setting how things print.
List of set print subcommands:
... snip ...
set print param-none -- This command is not documented.
... snip ...
And after my patch:
(gdb) python Param_None ('print param-none')
(gdb) help set print
set print, set pr, set p
Generic command for setting how things print.
List of set print subcommands:
... snip ...
set print param-none -- Set the current value of 'print param-none'.
... snip ...
This seems slightly less helpful than before, but I don't think its
terrible.
Additionally, I've changed what we print when the get_show_string
method is not provided in Python.
Back when gdb.Parameter was first added to GDB, we didn't provide a
show function when registering the internal command object within
GDB. As a result, GDB would make use of its "magic" mangling of the
show_doc string to create a sentence that would display the current
value (see deprecated_show_value_hack in cli/cli-setshow.c).
However, when we added support for the get_show_string method to
gdb.Parameter, there was an attempt to maintain backward compatibility
by displaying the show_doc string with the current value appended, see
get_show_value in py-param.c. Unfortunately, this isn't anywhere
close to what deprecated_show_value_hack does, and the results are
pretty poor, for example, this is GDB before my patch:
(gdb) show param-none
This command is not documented. off
I think we can all agree that this is pretty bad.
After my patch, we how show this:
(gdb) show param-none
The current value of 'param-none' is "off".
Which at least is a real sentence, even if it's not very informative.
This patch does change the way that the Python API behaves slightly,
but only in the cases when the user has missed providing GDB with some
information. In most cases I think the new behaviour is a lot better,
there's the one case (noted above) which is a bit iffy, but I think is
still OK.
I've updated the existing gdb.python/py-parameter.exp test to cover
the modified behaviour.
Finally, I've updated the documentation to (I hope) make it clearer
how the various bits of help text come together.
