A recent change in the compiler highlighted a small weakness in
the function reading the contents of the Ada Task Control Block
(ATCB -- the data that allows us to inspect Ada tasks). As a result,
anytime we read it, we started getting some warnings. For instance,
using the gdb.ada/tasks.exp testcase...
$ gnatmake -g foo.adb
$ gdb foo
(gdb) b foo.adb:60
Breakpoint 1 at 0x403e07: file foo.adb, line 60.
(gdb) run
[...]
Thread 1 "foo" hit Breakpoint 1, foo () at foo.adb:60
60 for J in Task_List'Range loop -- STOP_HERE
... we can see that the "info tasks" command produces some warnings,
followed by the correct output.
(gdb) info tasks
!! -> warning: array or string index out of range
!! -> warning: array or string index out of range
!! -> warning: array or string index out of range
!! -> warning: array or string index out of range
ID TID P-ID Pri State Name
* 1 654050 48 Runnable main_task
2 654ef0 1 48 Accept or Select Term task_list(1)
3 658680 1 48 Accept or Select Term task_list(2)
4 65be10 1 48 Accept or Select Term task_list(3)
The problem comes from the fact that read_atcb, the function responsible
for loading the contents of the ATCB, blindly tries to read some data
which is only relevant when a task is waiting for another task on
an entry call. A comment in that code's section gives a hint as to
how the information is meant to be decoded:
/* Let My_ATCB be the Ada task control block of a task calling the
entry of another task; then the Task_Id of the called task is
in My_ATCB.Entry_Calls (My_ATCB.ATC_Nesting_Level).Called_Task. */
What the comment shows is that, to get the Id of the task being called,
one has to go through the entry calls field, which is an array pointer.
Up to now, we were lucky that, for tasks that are _not_ waiting on an
entry call, its ATCB atc_nesting_level used to be set to 1, and so
we were able to silently read some irrelevant data. But a recent change
now causes this field to be zero instead, and this triggers the warning,
since we are now trying to read outside of the array's range (arrays
in Ada often start at index 1, as is the case here).
We avoid this issue by simply only reading that data when the data
is actually known to be relevant (state == Entry_Caller_Sleep).
This, in turn, allows us to simplify a bit the use of the task_info->state
field, where we no longer need to check task the task has a state equal
to Entry_Caller_Sleep before using this field. Indeed, with this new
approach, we now know that, unless task_info->state == Entry_Caller_Sleep,
the state is now guaranteed to be zero. In other words, we no longer set
task_info->called_task to some random value, forcing to check the task's
state first as a way to verify that the data is not random.
gdb/ChangeLog:
* ada-lang.c (read_atcb): Only set task_info->called_task if
task_info->state == Entry_Caller_Sleep.
(print_ada_task_info): Do not check task_info->state before
checking task_info->called_task.
(info_task): Likewise.
The purpose of this patch is not to fix a bug per se, but rather
to robustify this function to make sure it never returns a struct
ada_task_info where some of the fields are left uninitialized.
Reading the current implementation, it attempts to methodically
set them all one by one: but it's not excluded that a future
change might miss something. A memset is cheap and make sure that
this function returns repeatable results.
This in turns allows us to remove some assignments which have become
redundant.
gdb/ChangeLog:
* ada-tasks.c (read_atcb): Clear task_info before computing
the value of each of its fields.
* objdump.c (long_options): Have the --disassemble option take an
optional argument.
(usage): Add description for the `symbol' argument to the
--disassemble option.
(disasm_sym): New file private variable.
(struct objdump_disasm_info): New field `symbol'.
(disassemble_section): Introduce `do_print' local variable
to control whether objdump displays the result of disassembling
for a symbol or not.
(main): Set `symbol' file private variable if the option argument
for the --disassemble option is given.
* doc/binutils.texi (objdump): Add description for the option
argument.
* NEWS: Mention the new feature.
* testsuite/binutils-all/objdump.exp: Add tests of the -d and
--disassemble=<symbol> options.
* testsuite/binutils-all/bintest.s: Add more symbols and code.
* testsuite/binutils-all/readelf.s: Update expected output.
* testsuite/binutils-all/readelf.ss-64: Likewise.
* testsuite/binutils-all/readelf.ss-mips: Likewise.
* testsuite/binutils-all/readelf.ss-tmips: Likewise.
bfd * mach-o.h: Add new enums for BFD_MACH_O_PLATFORM_MACOS,
BFD_MACH_O_PLATFORM_IOS, BFD_MACH_O_PLATFORM_TVOS,
BFD_MACH_O_PLATFORM_WATCHOS, BFD_MACH_O_PLATFORM_BRIDGEOS,
BFD_MACH_O_TOOL_CLANG, BFD_MACH_O_TOOL_SWIFT, BFD_MACH_O_TOOL_LD.
(struct bfd_mach_o_note_command): New.
(struct bfd_mach_o_build_version_tool): New.
(struct bfd_mach_o_build_version_command): New.
(bfd_mach_o_read_version_min): Don't split version into
a few fields. Rename reserved to sdk.
* mach-o.c (bfd_mach_o_read_version_min): Don't split version into a
few fields. Rename reserved to sdk.
(bfd_mach_o_read_command): Handle LC_VERSION_MIN_TVOS, LC_NOTE,
LC_BUILD_VERSION.
(bfd_mach_o_read_note): New.
(bfd_mach_o_read_build_version): New.
PR 23728
binutils* od-macho.c (printf_version): New.
(dump_load_command): Use it to print version. Print sdk version. Print
version info for watchOS and tvOS. Print LC_NOTE, LC_BUILD_VERSION.
(dump_buld_version): New.
(bfd_mach_o_platform_name): New
(bfd_mach_o_tool_name): New
* mach-o/external.h (mach_o_nversion_min_command_external): Rename
reserved to sdk.
(mach_o_note_command_external): New.
(mach_o_build_version_command_external): New.
* mach-o/loader.h (BFD_MACH_O_LC_VERSION_MIN_TVOS): Define.
(BFD_MACH_O_LC_NOTE): Define.
In this commit:
commit eb77c9df9f
Date: Thu Oct 18 14:04:27 2018 +0100
gdb: Handle ICC's unexpected void return type
A potential dereference of a NULL pointer was introduced if a
DW_TAG_base_type is missing a DW_AT_name attribute.
I have taken this opportunity to fix a slight confusion that existed
in the test also added in the above commit, the test had two C
variables, declared like this:
int var_a = 5;
void *var_ptr = &var_a;
However, the fake DWARF in the test script declared them like this:
void var_a = 5;
void *var_ptr = &var_a;
This wasn't a problem as the test never uses 'var_a' directly, this
only exists so 'var_ptr' can be initialised. However, it seemed worth
fixing.
I've also added a test for a DW_TAG_base_type with a missing
DW_AT_name, as clearly there's not test currently that covers this
(the original patch tested cleanly). I can confirm that the new test
causes GDB to crash before this patch, and passes with this patch.
gdb/ChangeLog:
* dwarf2read.c (dwarf2_init_integer_type): Check for name being
NULL before dereferencing it.
gdb/testsuite/ChangeLog:
* gdb.dwarf2/void-type.exp: Rename types, and make var_a an 'int'.
* gdb.dwarf2/missing-type-name.exp: New file.
Consider the test-case from this patch, compiled with O0.
The executable segfaults, and generates a core dump:
...
$ ./a.out
Segmentation fault (core dumped)
...
When loading the core file, limiting stack size to 4MB, gdb crashes:
...
$ ulimit -s 4096
$ gdb -batch ./a.out core.saved
[New LWP 19379]
Segmentation fault (core dumped)
...
The crash originates here in linux_vsyscall_range_raw, where we call alloca
with phdrs_size == 4194112 (roughly 4MB):
...
phdrs = (Elf_Internal_Phdr *) alloca (phdrs_size);
...
While for this test-case gdb runs fine with the system default stack limit of
8MB, there are cases reported of 12MB phdrs_size where gdb also crashes with
the system default stack limit.
Fix this by using xmalloc instead of alloca, which prevents the crash provided
the stack limit is at least 112kb.
Build and reg-tested on x86_64-linux.
2018-11-06 Tom de Vries <tdevries@suse.de>
* linux-tdep.c (linux_vsyscall_range_raw): Use xmalloc to allocate
program headers.
* gdb.base/many-headers.c: New test.
* gdb.base/many-headers.exp: New file.
RISC-V puts a global variable in .sdata by default, which causes the
add-symbol-file commands with -s .data to fail as there is no .data section.
This fixes 3 testsuite failures.
gdb/testsuite/
* gdb.base/code_elim.exp: For riscv, set additional_flags
to include -msmall-data-limit=0.
gdb/
2018-11-06 Max Filippov <jcmvbkbc@gmail.com>
* configure.tgt (xtensa*-*-linux*): Change to xtensa*-*-*linux*
so that it applies to uclinux as well.
GDB tries to dereference the frame pointer in arm_scan_prologue as a
last resort to create frame information.
However, the more recent AAPCS ABI does not make use of a frame pointer.
This patch checks whether the specified arm_abi is AAPCS before
dereferencing the "frame pointer". If so, just return as efforts to use
it for restoring frame information won't work.
gdb/ChangeLog
2018-11-06 Marius Muench <marius.muench@eurecom.fr>
* arm-tdep.c (arm_scan_prologue): Don't dereference FP reg
when on AAPCS.
This permits reading the value of the SSTATUS CSR returned by ptrace()
for live FreeBSD/riscv processes.
* riscv-fbsd-nat.c (getregs_supplies): Return true for
RISCV_CSR_SSTATUS_REGNUM.
Add --enable-x86-feature and --disable-x86-feature options to elfedit
to set and clear the IBT and SHSTK bits in program property in ELF
executables and shared objects.
binutils/
* doc/binutils.texi: Document --enable-x86-feature and
--disable-x86-feature options for elfedit.
* elfedit.c: Include "config.h" and <sys/mman.h>.
(enable_x86_features): New.
(disable_x86_features): Likewise.
(update_gnu_property): Likewise.
(elf_x86_feature): Likewise.
(process_file): Call update_gnu_property on ET_EXEC or ET_DYN
file.
(command_line_switch): Add OPTION_ENABLE_X86_FEATURE and
OPTION_DISABLE_X86_FEATURE.
(options): Add--enable-x86-feature and --disable-x86-feature.
(usage): Likewise.
(main): Handle OPTION_ENABLE_X86_FEATURE and
OPTION_DISABLE_X86_FEATURE.
ld/
* testsuite/config/default.exp (ELFEDIT): New.
* testsuite/ld-elf/linux-x86.exp (elfedit_test): New proc.
Run elfedit tests.
* testsuite/ld-elf/x86-feature-1a.rd: New file.
* testsuite/ld-elf/x86-feature-1b.rd: Likewise.
* testsuite/ld-elf/x86-feature-1c.rd: Likewise.
* testsuite/ld-elf/x86-feature-1d.rd: Likewise.
* testsuite/ld-elf/x86-feature-1e.rd: Likewise.
The PE target can insert NOP's for padding to 4 byte alignment.
This was causing a testcase failure, this commit fixes the testcase.
This commit also escapes some full-stops in the testcase regexp.
2018-11-06 Matthew Malcomson <matthew.malcomson@arm.com>
* testsuite/gas/arm/neon-cond-bad_t2.d: Fix testcase for PE
target.
VCVT between f16 and f32 is an Advanced SIMD instruction.
Not all the VCVT alternatives need neon, hence the check for neon is in
the encode function.
The check on neon for VCVT.f16.f32 (and vice versa) is missing.
vshcmd: > echo 'vcvt.f16.f32 d1, q1' | gas/as-new -mfpu=vfpxd -march=armv8.5-a -
testdir [15:59:10] $
Also, the handling of the condition code behaves differently to other
SIMD instructions -- no error message is produced when assembling an
instruction with a condition code suffix despite the arm encoding not
allowing a condition code. (n.b. the actual binary produced is
independent of the suffix).
The instruction should be treated similarly to VSUBL that has the same
caveat of "must be unconditional" describing the {<c>} symbol. vcvt
half-precision to single precision found in F6.1.58 in the ARM
Architecture Reference Manual issue C.a, vsubl found in F6.1.240 in
the ARM Architecture Reference Manual issue C.a
2018-11-06 Matthew Malcomson <matthew.malcomson@arm.com>
* config/tc-arm.c (do_neon_cvt_1): Add check for neon and condition
codes to half-precision conversion.
* testsuite/gas/arm/neon-cond-bad-inc.s: Check vcvteq disallowed.
* testsuite/gas/arm/neon-cond-bad.l: Likewise.
* testsuite/gas/arm/neon-cond-bad_t2.d: Check vcvteq allowed in IT
block.
* testsuite/gas/arm/vfp-bad.l: Ensure vcvt doesn't work without neon.
* testsuite/gas/arm/vfp-bad.s: Likewise.
This patch addresses the following
1) Adding ARMv8.5-A in select_arm_features.
2) Updating the feature macro so that the new ARM_EXT2_* features for
Armv8.5-A are moved to ARM_AEXT2_V8_5A.
*** opcodes/ChangeLog ***
2018-11-06 Sudakshina Das <sudi.das@arm.com>
* arm-dis.c (select_arm_features): Update bfd_mach_arm_8
with Armv8.5-A. Remove reduntant ARM_EXT2_FP16_FML.
*** include/ChangeLog ***
2018-11-06 Sudakshina Das <sudi.das@arm.com>
* opcode/arm.h (ARM_ARCH_V8_5A): Move ARM_EXT2_PREDRES and
ARM_EXT2_SB to ...
(ARM_AEXT2_V8_5A): Here.
The instruction mask bits should never overlap any of the operands,
nor should operand bits overlap, but some operands weren't checked.
This patch arranges to check the omitted operands, using a mask
returned by the operand->insert function. Some tweaking of various
insert functions is needed to support this: The error case must set
field bits.
Since I was looking at the insert functions, I tidied some dead code
and simplified some of the powerpc_operands entries.
gas/
* config/tc-ppc.c (insn_validate): Don't ignore mask in
PPC_OPSHIFT_INV case. Call the insert function to calculate
a mask.
opcodes/
* ppc-opc.c (insert_arx, insert_ary, insert_rx, insert_ry, insert_ls),
(insert_evuimm1_ex0, insert_evuimm2_ex0, insert_evuimm4_ex0),
(insert_evuimm8_ex0, insert_evuimm_lt8, insert_evuimm_lt16),
(insert_rD_rS_even, insert_off_lsp, insert_off_spe2, insert_Ddd):
Don't return zero on error, insert mask bits instead.
(insert_sd4h, extract_sd4h, insert_sd4w, extract_sd4w): Delete.
(insert_sh6, extract_sh6): Delete dead code.
(insert_sprbat, insert_sprg): Use unsigned comparisions.
(powerpc_operands <OIMM>): Set shift count rather than using
PPC_OPSHIFT_INV.
<SE_SDH, SE_SDW>: Likewise. Don't use insert/extract functions.
This adds another check that might have saved me a little time
recently if it had been present.
* config/tc-ppc.c (insn_validate): Check that optional operands
are not followed by non-optional operands.
For the flavors having a GPR operand EVEX.W is ignored outside of 64-bit
mode. The mnemonic should therefore not be KMOVQ, the GPR operand should
not name a non-existing 64-bit register, just like is already the case
for the AVX counterparts, and the Disp8 scaling factor should be 4
rather than 8.
PEXTR{B,W} and PINSR{B,W}, just like for AVX512BW, are WIG, no matter
that the SDM uses a nonstandard description of that fact.
PEXTRD, even with EVEX.W set, ignores that bit outside of 64-bit mode,
just like its AVX counterpart.
Many VEX-/EVEX-encoded instructions accessing GPRs become WIG outside of
64-bit mode. The respective templates should specify neither VexWIG nor
VexW0, but instead the setting of the bit should be determined from
- REX.W in 64-bit mode,
- the setting established through -mvexwig= / -mevexwig= otherwise.
This implies that the evex-wig2 testcase needs to go away, as being
wrong altogether.
A few test additions desirable here will only happen in later patches,
as the disassembler needs adjustments first.
Once again SSE2AVX templates are left alone, for it being unclear what
the behavior there should be.
Quite a few templates were marked LIG while really the insns aren't.
Introduce descriptive shorthands once again, instead of continuing to
use the less legible original forms.
The 0F C5 encoding is indeed a load type one (just that memory operands
are not permitted), while the 0F 3A 15 encoding is obviously a store.
Allow the pseudo prefixes to be used to select between them.
Also move (without any change) the secondary AVX512BW templates next to
the primary one.
Commits 6865c0435a ("x86: Support VEX/EVEX WIG encoding") and 6fa52824c3
("x86: Replace VexW=3 with VexWIG") omitted quite a few templates, oddly
enough in some cases despite testcases getting added (which then were
recorded with wrong expected output).
Also adjust VPMAXUB's attributes in the AVX512BW case to match ordering
of that of neighboring templates.
For the moment SSE2AVX templates are left alone, as it isn't clear
whether they were intentionally left untouched by the original commits
(the descriptions don't say either way).
In this context I question the decision in commit 0375113302 ("x86: Add
-mvexwig=[0|1] option to assembler") to move the logic to determine the
value of the W bit ahead of the decision whether to use 2-byte VEX:
While I can see this as one possible interpretation of -mvexwig=, the
other alternative (setting the value of the bit only if it actually
exists in the encoding) looks as reasonable to me, and perhaps even more
in line with us generally trying to pick the shortest encoding.
When current function changes after a next/step, GDB shows a message such as:
(gdb) s
info_fun1 ()
at /bd/home/philippe/gdb/git/build_smallthing/gdb/testsuite/../../../smallthing/gdb/testsuite/gdb.base/info_qt.c:41
41 info_qt_inc++;
(gdb)
Valgrind reports a 4K definite leak for each such message (full stacktrace of
the leak below).
This patch fixes this leak, by transferring the current s->fullname to the
unique_xmalloc_ptr fullname given to find_and_open_source.
Note that I do not understand why find_and_open_source always tries to
re-execute the substitution rules on the provided fullname, as source.c
symtab_to_fullname just blindly returns a non NULL s->fullname, counting on
forget_cached_source_info to be called if search dir or substitution rules are
changed. Similarly, psymtab_to_fullname also just returns a non NULL
ps->fullname.
==15309== VALGRIND_GDB_ERROR_BEGIN
==15309== 69,632 bytes in 17 blocks are definitely lost in loss record 3,158 of 3,186
==15309== at 0x4C2BE2D: malloc (vg_replace_malloc.c:299)
==15309== by 0x5BF0987: realpath@@GLIBC_2.3 (canonicalize.c:78)
==15309== by 0x41F713: gdb_realpath(char const*) (pathstuff.c:72)
==15309== by 0x608833: openp(char const*, enum_flags<openp_flag>, char const*, int, std::unique_ptr<char, gdb::xfree_deleter<char> >*) (source.c:861)
==15309== by 0x608B89: find_and_open_source(char const*, char const*, std::unique_ptr<char, gdb::xfree_deleter<char> >*) (source.c:1049)
==15309== by 0x608D0B: open_source_file(symtab*) (source.c:1074)
==15309== by 0x609101: print_source_lines_base(symtab*, int, int, enum_flags<print_source_lines_flag>) (source.c:1291)
==15309== by 0x614ADF: print_frame_info(frame_info*, int, print_what, int, int) (stack.c:911)
==15309== by 0x614C45: print_stack_frame(frame_info*, int, print_what, int) (stack.c:181)
==15309== by 0x511D5E: print_stop_location (infrun.c:8044)
==15309== by 0x511D5E: print_stop_event(ui_out*) (infrun.c:8061)
==15309== by 0x40DD6D: cli_on_normal_stop(bpstats*, int) (cli-interp.c:145)
==15309== by 0x512409: operator() (functional:2127)
==15309== by 0x512409: notify (observable.h:106)
==15309== by 0x512409: normal_stop() (infrun.c:8334)
==15309== by 0x5156D8: fetch_inferior_event(void*) (infrun.c:3955)
==15309== by 0x4B3EEC: gdb_wait_for_event(int) (event-loop.c:859)
==15309== by 0x4B3FF6: gdb_do_one_event() [clone .part.4] (event-loop.c:322)
==15309== by 0x4B41B4: gdb_do_one_event (common-exceptions.h:219)
==15309== by 0x4B41B4: start_event_loop() (event-loop.c:371)
==15309== by 0x551217: captured_command_loop() (main.c:330)
==15309== by 0x55220C: captured_main (main.c:1177)
==15309== by 0x55220C: gdb_main(captured_main_args*) (main.c:1193)
==15309== by 0x29B4F7: main (gdb.c:32)
==15309==
==15309== VALGRIND_GDB_ERROR_END
gdb/ChangeLog
2018-11-04 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* source.c (open_source_file): Fix leak by transferring the
current s->fullname to the unique_xmalloc_ptr fullname given
to find_and_open_source.
commit e60f4d3bda
Author: H.J. Lu <hjl.tools@gmail.com>
Date: Mon Nov 5 09:01:26 2018 -0800
x86: Disable GOT relaxation with data prefix
Since linker GOT relaxation isn't valid for 16-bit GOT access, we should
disable GOT relaxation with data prefix.
Valgrind detected a leak for the line:
type = xstrdup ("auto");
as the compile probably dropped the type variable completely, as its
only usage was this initialization.
So, remove the useless variable.
Add AC_FUNC_MMAP to configure.ac so that HAVE_MMAP will be checked in
objdump.c and mmap is used if available.
* configure.ac (AC_FUNC_MMAP): New.
* config.in: Regenerated.
* configure: Likewise.
This patch adds support for debugging Ravenscar tasks, similar to what
is done for ppc and sparc.
gdb/ChangeLog:
* aarch64-ravenscar-thread.h, aarch64-ravenscar-thread.c:
New files.
* aarch64-tdep.c: #include "aarch64-ravenscar-thread.h".
(aarch64_gdbarch_init): Add call to register_aarch64_ravenscar_ops.
* Makefile.in (ALL_64_TARGET_OBS): Add aarch64-ravenscar-thread.o.
(HFILES_NO_SRCDIR): Add aarch64-ravenscar-thread.h.
(ALLDEPFILES): Add aarch64-ravenscar-thread.c.
* configure.tgt (cpu_obs) [aarch64*-*-*]: Add ravenscar-thread.o
and aarch64-ravenscar-thread.o.
* NEWS: Add entry documenting Ravenscar tasking support
on AArch64 ELF.
Cleans a few more test files.
* Makefile.am (MOSTLYCLEANFILES): Define.
* Makefile.in: Regnerate.
* testsuite/Makefile.am (MOSTLYCLEANFILES): Add ver_test_14 and
gnu_property_test.
* testsuite/Makefile.in: Regnerate.
