If you should somehow link non-pic objects into a PIE or shared
library, resulting in an object with DT_TEXTREL (text relocations)
set, and your executable or shared library also contains GNU indirect
functions, then you're in trouble. To apply dynamic relocations
ld.so will make the text segment writable. On most systems this will
make the text segment non-executable, which will then result in a
segfault when ld.so tries to run ifunc resolvers when applying
relocations against ifuncs.
This patch teaches PowerPC ld to detect the situation, and warn.
* elf64-ppc.c (struct ppc_link_hash_table): Add
local_ifunc_resolver and maybe_local_ifunc_resolver.
(ppc_build_one_stub): Set flags on emitting dynamic
relocation to ifunc.
(ppc64_elf_relocate_section): Likewise.
(ppc64_elf_finish_dynamic_symbol): Likewise.
(ppc64_elf_finish_dynamic_sections): Error on DT_TEXTREL with
local dynamic relocs to ifuncs.
* elf32-ppc.c (struct ppc_elf_link_hash_table): Add
local_ifunc_resolver and maybe_local_ifunc_resolver.
(ppc_elf_relocate_section): Set flag on emitting dynamic
relocation to ifuncs.
(ppc_elf_finish_dynamic_symbol): Likewise.
(ppc_elf_finish_dynamic_sections): Error on DT_TEXTREL with local
dynamic relocs to ifuncs.
This is one of the rare to_fetch/store_registers implementations that will
still rely (for now) on inferior_ptid (because of the memory read/write
operations). We therefore have to add a save/restore of inferior_ptid. We'll
be able to remove it when we make the memory operations accept the ptid as a
parameter.
gdb/ChangeLog:
* bsd-uthread.c (bsd_uthread_fetch_registers,
bsd_uthread_store_registers): Use ptid from regcache, set and
restore inferior_ptid.
As Gareth McMullin <gareth@blacksphere.co.nz> reports at
<https://sourceware.org/ml/gdb-patches/2017-02/msg00560.html>, the
timeout mechanism in ser-unix.c was broken by commit 048094acc
("target remote: Don't rely on immediate_quit (introduce quit
handlers)").
Instead of applying a local fix, and since we now finally always use
interrupt_select [1], let's get rid of hardwire_readchar entirely, and
use ser_base_readchar instead, which has similar timeout handling,
except for the bug.
Smoke tested with:
$ socat -d -d pty,raw,echo=0 pty,raw,echo=0
2017/03/14 14:08:13 socat[4994] N PTY is /dev/pts/14
2017/03/14 14:08:13 socat[4994] N PTY is /dev/pts/15
2017/03/14 14:08:13 socat[4994] N starting data transfer loop with FDs [3,3] and [5,5]
$ gdbserver /dev/pts/14 PROG
$ gdb PROG -ex "tar rem /dev/pts/15"
and then a few continues/ctrl-c's, plus killing gdbserver and socat.
[1] - See FIXME comments being removed.
gdb/ChangeLog:
2017-03-17 Pedro Alves <palves@redhat.com>
PR remote/21188
* ser-base.c (ser_base_wait_for): Add comment.
(do_ser_base_readchar): Improve comment based on the ser-unix.c's
version.
* ser-unix.c (hardwire_raw): Remove reference to
scb->current_timeout.
(wait_for, do_hardwire_readchar, hardwire_readchar): Delete.
(hardwire_ops): Install ser_base_readchar instead of
hardwire_readchar.
* serial.h (struct serial) <current_timeout, timeout_remaining>:
Remove fields.
Fix this the same way gdb/python/lib/gdb/printing.py handles it.
gdb/Changelog:
2017-03-17 Jonah Graham <jonah@kichwacoders.com>
PR gdb/19637
* python/lib/gdb/printer/bound_registers.py: Add support for
Python 3.
PR 21248
* ppc-opc.c (powerpc_opcodes): Enable mfivor32, mfivor33,
mtivor32, and mtivor33 for e6500. Move mfibatl and mfibatu after
those spr mnemonics they alias. Similarly for mtibatl, mtibatu.
Recently I fixed a bug that caused a DW_OP_implicit_pointer with non-zero
offset into a DW_OP_implicit_value to be handled incorrectly on big-endian
targets. GDB ignored the offset and copied the wrong bytes:
https://sourceware.org/ml/gdb-patches/2017-01/msg00251.html
But there is still a similar issue when a DW_OP_implicit_pointer points
into a DW_OP_stack_value instead; and again, the offset is ignored. There
is an important difference, though: While implicit values are treated like
blocks of data and anchored at the lowest-addressed byte, stack values
traditionally contain integer numbers and are anchored at the *least
significant* byte. Also, stack values do not come in varying sizes, but
are cut down appropriately when used. Thus, on big-endian targets the
scenario looks like this (higher addresses shown right):
|<- - - - - Stack value - - - - - - ->|
| |
|<- original object ->|
|
| offset ->|####|
^^^^
de-referenced
implicit pointer
(Note how the original object's size influences the position of the
de-referenced implicit pointer within the stack value. This is not the
case for little-endian targets, where the original object starts at offset
zero within the stack value.)
This patch implements the logic indicated in the above diagram and adds an
appropriate test case. A new function dwarf2_fetch_die_type_sect_off is
added; it is used for retrieving the original object's type, so its size
can be determined. That type is passed to dwarf2_evaluate_loc_desc_full
via a new parameter.
gdb/ChangeLog:
* dwarf2loc.c (indirect_synthetic_pointer): Get data type of
pointed-to DIE and pass it to dwarf2_evaluate_loc_desc_full.
(dwarf2_evaluate_loc_desc_full): New parameter subobj_type; rename
byte_offset to subobj_byte_offset. Fix the handling of
DWARF_VALUE_STACK on big-endian targets when coming via an
implicit pointer.
(dwarf2_evaluate_loc_desc): Adjust call to
dwarf2_evaluate_loc_desc_full.
* dwarf2loc.h (dwarf2_fetch_die_type_sect_off): New declaration.
* dwarf2read.c (dwarf2_fetch_die_type_sect_off): New function.
gdb/testsuite/ChangeLog:
* lib/dwarf.exp: Add support for DW_OP_implicit_pointer.
* gdb.dwarf2/nonvar-access.exp: Add test for stack value location
and implicit pointer into such a location.
include * elf/common.h (GNU_BUILD_ATTRIBUTE_SHORT_ENUM): New GNU BUILD
note type.
binutils * readelf.c (print_gnu_build_attribute_name): Add support for
GNU_BUILD_ATTRIBUTE_SHORT_ENUM.
This patch adds the support for these instructions in arm process
record.
gdb:
2017-03-16 Yao Qi <yao.qi@linaro.org>
* arm-tdep.c (thumb_record_misc): Decode CBNZ, CBZ, REV16,
and REVSH instructions.
I look at some fails in gdb.reverse/solib-precsave.exp in -mthumb,
they are caused by some bugs on decoding these three instructions,
uxtb, ldr and mrc. This patch adds unit tests against these three
instructions, and fix these bugs by re-organizing the code to match
the table in ARM ARM.
gdb:
2017-03-16 Yao Qi <yao.qi@linaro.org>
* arm-tdep.c [GDB_SELF_TEST]: include "selftests.h".
(arm_record_test): Declare.
(_initialize_arm_tdep) [GDB_SELF_TEST]: call register_self_test.
(thumb_record_ld_st_reg_offset): Rewrite the opcode matching to
align with the manual.
(thumb_record_misc): Adjust the code order to align with the
manual.
(thumb2_record_decode_insn_handler): Fix instruction matching.
(instruction_reader_thumb): New class.
(arm_record_test): New function.
This patch adds an abstract class abstract_memory_reader a
and pass it to the code reading instructions in arm process record,
rather than using target_read_memory to read from real target. This
paves the way for adding more unit tests to arm process record.
gdb:
2017-03-16 Yao Qi <yao.qi@linaro.org>
* arm-tdep.c (abstract_memory_reader): New class.
(instruction_reader): New class.
(extract_arm_insn): Add argument 'reader'. Callers updated.
(decode_insn): Likewise.
This patch keeps the Scheme side of lazy string handling in sync
with the python size, bringing over fixes for
PRs python/17728, python/18439, python/18779.
gdb/ChangeLog:
* guile/scm-lazy-string.c (lazy_string_smob): Clarify use of LENGTH
member. Change type of TYPE member to SCM. All uses updated.
(lsscm_make_lazy_string_smob): Add assert.
(lsscm_make_lazy_string): Flag bad length values.
(lsscm_elt_type): New function.
(gdbscm_lazy_string_to_value): Rewrite to use
lsscm_safe_lazy_string_to_value.
(lsscm_safe_lazy_string_to_value): Fix handling of TYPE_CODE_PTR.
* guile/scm-value.c (gdbscm_value_to_lazy_string): Flag bad length
values. Fix TYPE_CODE_PTR. Handle TYPE_CODE_ARRAY. Handle typedefs
in incoming type.
* guile/guile-internal.h (tyscm_scm_to_type): Declare.
* guile/scm-type.c (tyscm_scm_to_type): New function.
gdb/testsuite/ChangeLog:
* gdb.guile/scm-value.c (main) Delete locals sptr, sn.
* gdb.guile/scm-lazy-string.c: New file.
* gdb.guile/scm-value.exp: Move lazy string tests to ...
* gdb.guile/scm-lazy-string.exp: ... here, new file. Add more tests
for pointer, array, typedef lazy strings.
gdb/ChangeLog:
PR python/17728, python/18439, python/18779
* python/py-lazy-string.c (lazy_string_object): Clarify use of LENGTH
member. Change type of TYPE member to PyObject *. All uses updated.
(stpy_convert_to_value): Fix handling of TYPE_CODE_PTR.
(gdbpy_create_lazy_string_object): Flag bad length values.
Handle TYPE_CODE_ARRAY with possibly different user-provided length.
Handle typedefs in incoming type.
(stpy_lazy_string_elt_type): New function.
(gdbpy_extract_lazy_string): Call it.
* python/py-value.c (valpy_lazy_string): Flag bad length values.
Fix handling of TYPE_CODE_PTR. Handle TYPE_CODE_ARRAY. Handle
typedefs in incoming type.
gdb/testsuite/ChangeLog:
PR python/17728, python/18439, python/18779
* gdb.python/py-value.c (main) Delete locals sptr, sn.
* gdb.python/py-lazy-string.c (pointer): New typedef.
(main): New locals ptr, array, typedef_ptr.
* gdb.python/py-value.exp: Move lazy string tests to ...
* gdb.python/py-lazy-string.exp: ... here. Add more tests for pointer,
array, typedef lazy strings.
The expectation in gdb.cp/m-static.exp for the ptype of
single_constructor is to get in the result of destructor with the
following prototype: ~single_constructor(int).
Yet, m-static.cc declares the destructor as ~single_constructor(). This
commit fixes the expectation.
2017-03-16 Thomas Preud'homme <thomas.preudhomme@arm.com>
gdb/testsuite/
* gdb.cp/m-static.exp: Fix expectation for prototype of
test5.single_constructor and single_constructor::single_constructor.
In a later commit I'll be adding a new version of the ".nt" flag for an
ARC700 extension (NPS400) which does not require this same special
handling.
In this commit I have restricted the special flag handling to only apply
if we are assembling for ARCv2. This is a restructuring commit, and
there should be no user visible changes after this commit.
gas/ChangeLog:
* config/tc-arc.c (assemble_insn): Only handle ".t" and ".nt"
specially for ARCv2.
gold/
* mips.cc (Mips_got_entry::hash()): Shift addend to reduce
possibility of collisions.
(Mips_got_entry::equals): Fix case for GOT_TLS_LDM
entries.
gold/
* mips.cc (Mips_relobj::merge_processor_specific_data_): New data
member.
(Mips_relobj::merge_processor_specific_data): New method.
(Mips_relobj::do_read_symbols): Set merge_processor_specific_data_
to false, only if the input file is a binary or if object has no
contents except the section name string table and an empty symbol
table with the undefined symbol.
(Target_mips::do_finalize_sections): Refactor. Skip empty object files
for merging processor-specific data.
gold/
* mips.cc (Target_mips::Relocate::calculated_value_): New data
member.
(Target_mips::Relocate::calculate_only_): Likewise.
(Target_mips::Relocate::relocate): Handle multiple consecutive
relocations with the same offset.
gold/
* mips.cc (symbol_refs_local): Return false if a symbol
is from a dynamic object.
(Target_mips::got_section): Make _GLOBAL_OFFSET_TABLE_ STV_HIDDEN.
(Target_mips::set_gp): Refactor. Make _gp STT_NOTYPE and
STB_LOCAL.
(Target_mips::do_finalize_sections): Set _gp after all the checks
for creating .got are done.
(Target_mips::Scan::global): Remove unused code.
- They can accept 0 in imm field
2017-03-14 Kito Cheng <kito.cheng@gmail.com>
* riscv-opc.c (riscv_opcodes> <c.li>: Use the 'o' immediate encoding.
<c.andi>: Likewise.
<c.addiw> Likewise.
When inf_ptrace_xfer_partial performs a memory transfer via ptrace with
PT_READ_I, PT_WRITE_I (aka PTRACE_PEEKTEXT, PTRACE_POKETEXT), etc., then
it currently transfers at most one word. This behavior yields degraded
performance, particularly if the caller has significant preparation work
for each invocation. And indeed it has for writing, in
memory_xfer_partial in target.c, where all of the remaining data to be
transferred is copied to a temporary buffer each time, for breakpoint
shadow handling. Thus large writes have quadratic runtime and can take
hours.
Note: On GNU/Linux targets GDB usually does not use
inf_ptrace_xfer_partial for large memory transfers, but attempts a single
read/write from/to /proc/<pid>/mem instead. However, the kernel may
reject writes to /proc/<pid>/mem (such as kernels prior to 2.6.39), or
/proc may not be mounted. In both cases GDB falls back to the ptrace
mechanism.
This patch fixes the performance issue by attempting to fulfill the whole
transfer request in inf_ptrace_xfer_partial, using a loop around the
ptrace call.
gdb/ChangeLog:
PR gdb/21220
* inf-ptrace.c (inf_ptrace_xfer_partial): In "case
TARGET_OBJECT_MEMORY", extract the logic for ptrace peek/poke...
(inf_ptrace_peek_poke): ...here. New function. Now also loop
over ptrace peek/poke until end of buffer or error.
gas/ChangeLog:
2017-03-02 Kuan-Lin Chen <rufus@andestech.com>
* config/tc-riscv.c (md_apply_fix): Set fx_frag and
fx_next->fx_frag for CFA_advance_loc relocations.
