Prior to the patch, addends for relocs were being adjusted even if
they went beyond an alignment boundary. This is wrong - to
preserve alignment constraints, the relaxation logic adds as many padding
bytes at the alignment boundary as was deleted, so addends beyond the
boundary should not be adjusted. avr-prop-7.s reproduces this
scenario.
Also, prior to this patch, the relaxation logic assumed that the addr
parameter pointed to the middle of the instruction to be deleted, and
that addr - count would therefore be the shrinked instruction's
address. This is true when actually shrinking instructions.
The alignment constraints handling logic also invokes the same logic
though, with addr as the starting offset of padding bytes and
with count as the number of bytes to be deleted. Calculating the
shrinked insn's address as addr - count is obviously wrong in this
case - that offset would point to count bytes before the last
non-padded byte. avr-prop-8.s reproduces this scenario.
To fix scenario 1, the patch adds an additional check to ensure reloc addends
aren't adjusted if they cross a shrink boundary. The shrink boundary
is either the section size or an alignment boundary. Addends pointing
at an alignment boundary don't need to be adjusted, as padding would
occur and keep the boundary the same. Addends pointing at section size
need to be adjusted though, as no padding occurs and the section size
itself would get decremented. The patch records whether padding
occured (did_pad) and uses that to detect and handle this condition.
To fix scenario 2, the patch adds an additional parameter
(delete_shrinks_insn) to elf32_avr_relax_delete_bytes to distinguish
instruction bytes deletion from padding bytes deletion. It then uses that to
correctly set shrinked_insn_address.
bfd/ChangeLog:
2016-09-02 Senthil Kumar Selvaraj <senthil_kumar.selvaraj@atmel.com>
PR ld/20545
* elf32-avr.c (elf32_avr_relax_delete_bytes): Add parameter
delete_shrinks_insn. Modify computation of shrinked_insn_address.
Compute shrink_boundary and adjust addend only if
addend_within_shrink_boundary.
(elf32_avr_relax_section): Modify calls to
elf32_avr_relax_delete_bytes to pass extra parameter.
ld/ChangeLog:
2016-09-02 Senthil Kumar Selvaraj <senthil_kumar.selvaraj@atmel.com>
PR ld/20545
* testsuite/ld-avr/avr-prop-7.d: New test.
* testsuite/ld-avr/avr-prop-7.s: New test.
* testsuite/ld-avr/avr-prop-8.d: New test.
* testsuite/ld-avr/avr-prop-8.s: New test.
This removes all support for building gdb & gdbserver with a C
compiler from gdb & gdbserver's build machinery.
gdb/ChangeLog:
2016-09-05 Pedro Alves <palves@redhat.com>
* NEWS: Mention that a C++ compiler is now required.
* Makefile.in (COMPILER, COMPILER_CFLAGS): Remove.
(COMPILE.pre, CC_LD): Use CXX directly.
(INTERNAL_CFLAGS_BASE): Use CXXFLAGS directly.
* acinclude.m4: Don't include build-with-cxx.m4.
* build-with-cxx.m4: Delete file.
* configure.ac: Remove GDB_AC_BUILD_WITH_CXX call.
* warning.m4: Assume $enable_build_with_cxx is yes.
* configure: Regenerate.
gdb/gdbserver/ChangeLog:
2016-09-05 Pedro Alves <palves@redhat.com>
* Makefile.in (COMPILER, COMPILER_CFLAGS): Remove.
(COMPILE.pre, CC_LD): Use CXX directly.
(INTERNAL_CFLAGS_BASE): Use CXXFLAGS directly.
* acinclude.m4: Don't include build-with-cxx.m4.
* configure.ac: Remove GDB_AC_BUILD_WITH_CXX call.
* configure: Regenerate.
This fixes the problem exercised by Kevin's test at:
https://sourceware.org/ml/gdb-patches/2016-08/msg00216.html
This was originally exposed by the OpenJDK Python-based unwinder.
If an unwinder attempts to call parse_and_eval from within its
sniffing method, GDB's unwinding machinery enters infinite recursion.
However, parse_and_eval is a pretty reasonable thing to call, because
Python/Scheme-based unwinders will often need to read globals out of
inferior memory. The recursion happens because:
- get_current_frame() is called soon after the target stops.
- current_frame is NULL, and so we unwind it from the sentinel frame
(which is special and has level == -1).
- We reach get_prev_frame_if_no_cycle, which does cycle detection
based on frame id, and thus tries to compute the frame id of the new
frame.
- Frame id computation requires an unwinder, so we go through all
unwinder sniffers trying to see if one accepts the new frame (the
current frame).
- the unwinder's sniffer calls parse_and_eval().
- parse_and_eval depends on the selected frame/block, and if not set
yet, the selected frame is set to the current frame.
- get_current_frame () is called again. current_frame is still NULL,
so ...
- recurse forever.
In Kevin's test at:
https://sourceware.org/ml/gdb-patches/2016-08/msg00216.html
gdb doesn't recurse forever simply because the Python unwinder
contains code to detect and stop the recursion itself. However, GDB
goes downhill from here, e.g., by showing the sentinel frame as
current frame (note the -1):
Breakpoint 1, ccc (arg=<unavailable>) at py-recurse-unwind.c:23
23 }
(gdb) bt
#-1 ccc (arg=<unavailable>) at py-recurse-unwind.c:23
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
That "-1" frame level comes from this:
if (catch_exceptions (current_uiout, unwind_to_current_frame,
sentinel_frame, RETURN_MASK_ERROR) != 0)
{
/* Oops! Fake a current frame? Is this useful? It has a PC
of zero, for instance. */
current_frame = sentinel_frame;
}
which is bogus. It's never correct to set the current frame to the
sentinel frame. The only reason this has survived so long is that
getting here normally indicates something wrong has already happened
before and we fix that. And this case is no exception -- it doesn't
really matter how precisely we managed to get to that bogus code (it
has to do with the the stash), because anything after recursion
happens is going to be invalid.
So the fix is to avoid the recursion in the first place.
Observations:
#1 - The recursion happens because we try to do cycle detection from
within get_prev_frame_if_no_cycle. That requires computing the
frame id of the frame being unwound, and that itself requires
calling into the unwinders.
#2 - But, the first time we're unwinding from the sentinel frame,
when we reach get_prev_frame_if_no_cycle, there's no frame chain
at all yet:
- current_frame is NULL.
- the frame stash is empty.
Thus, there's really no need to do cycle detection the first time we
reach get_prev_frame_if_no_cycle, when building the current frame.
So we can break the recursion by making get_current_frame call a
simplified version of get_prev_frame_if_no_cycle that results in
setting the current_frame global _before_ computing the current
frame's id.
But, we can go a little bit further. As there's really no reason
anymore to compute the current frame's frame id immediately, we can
defer computing it to when some caller of get_current_frame might need
it. This was actually how the frame id was computed for all frames
before the stash-based cycle detection was added. So in a way, this
patch reintroduces the lazy frame id computation, but unlike before,
only for the case of the current frame, which turns out to be special.
This lazyness, however, requires adjusting
gdb.python/py-unwind-maint.exp, because that assumes unwinders are
immediately called as side effect of some commands. I didn't see a
need to preserve the behavior expected by that test (all it would take
is call get_frame_id inside get_current_frame), so I adjusted the
test.
gdb/ChangeLog:
2016-09-05 Pedro Alves <palves@redhat.com>
PR backtrace/19927
* frame.c (get_frame_id): Compute the frame id if not computed
yet.
(unwind_to_current_frame): Delete.
(get_current_frame): Use get_prev_frame_always_1 to get the
current frame and assert that that always succeeds.
(get_prev_frame_if_no_cycle): Skip cycle detection if returning
the current frame.
gdb/testsuite/ChangeLog:
2016-09-05 Pedro Alves <palves@redhat.com>
PR backtrace/19927
* gdb.python/py-unwind-maint.exp: Adjust tests to not expect that
unwinders are immediately called as side effect of "source" or
"disable unwinder" commands.
* gdb.python/py-recurse-unwind.exp: Remove setup_kfail calls.
Currently gdb supports DW_OP_GNU_push_tls_address, but not
DW_OP_form_tls_address. I think it would be better if the toolchain
as a whole moved to using the standard opcode, and the prerequisite to
this is getting gdb to recognize it.
GCC can sometimes emit DW_OP_form_tls_address for emultls targets. As
far as I know, nobody has ever tried this with gdb (since it wouldn't
work at all).
I don't think there's a major drawback to using a single opcode for
all targets, because computing the location of a thread-local is
already target specific.
This is PR gdb/11616.
I don't know how to write a test case for this; though it's worth
noting that there aren't explicit tests for DW_OP_GNU_push_tls_address
either -- and if I change GCC, these paths will be tested to the same
extent they are now.
2016-09-02 Tom Tromey <tom@tromey.com>
PR gdb/11616:
* dwarf2read.c (decode_locdesc): Handle DW_OP_form_tls_address.
* dwarf2loc.c (dwarf2_compile_expr_to_ax): Handle
DW_OP_form_tls_address.
(locexpr_describe_location_piece): Likewise.
* dwarf2expr.h (struct dwarf_expr_context_funcs): Update comment.
* dwarf2expr.c (execute_stack_op): Handle DW_OP_form_tls_address.
(ctx_no_get_tls_address): Mention DW_OP_form_tls_address.
* compile/compile-loc2c.c (struct insn_info): Update comment.
(compute_stack_depth_worker): Handle DW_OP_form_tls_address.
reinsert_breakpoint is used for software single step, so it is more
clear to rename it to single_step_breakpoint. This was pointed out in
the review https://sourceware.org/ml/gdb-patches/2016-05/msg00429.html
I don't rename "other_breakpoint" in this patch.
gdb/gdbserver:
2016-09-02 Yao Qi <yao.qi@linaro.org>
* linux-low.c: Replace "reinsert_breakpoints" with
"single_step_breakpoints". Replace "reinsert breakpoints"
with "single-step breakpoints".
* mem-break.c: Likewise.
* mem-break.h: Likewise.
return-nodebug.exp does the test for various types, but we shouldn't
test with floating point type if gdb_skip_float_test returns true.
gdb/testsuite:
2016-09-02 Yao Qi <yao.qi@linaro.org>
* gdb.base/return-nodebug.exp: Skip the test if skip_float_test
is true and $type is "float" or "double".
We recently found a ARM kernel ptrace bug
http://lists.infradead.org/pipermail/linux-arm-kernel/2016-May/431962.html
Details can be found in the comment in gdb_skip_float_test. We can
skip floating point tests if the kernel bug is detected.
This patch adds more code in gdb_skip_float_test to detect the broken
ptrace on arm-linux. Such detection should be done at the beginning
of the test, because it starts a fresh GDB, so change the test cases
to invoke gdb_skip_float_test at the beginning of test, and use its
return value afterwards.
Since gdb_skip_float_test becomes a gdb_caching_proc, so it can't
have an argument, this patch also removes argument "msg", which isn't
useful.
gdb/testsuite:
2016-09-02 Yao Qi <yao.qi@linaro.org>
* gdb.arch/arm-neon.exp: Skip it if gdb_skip_float_test returns
true.
* gdb.base/call-ar-st.exp: Invoke gdb_skip_float_test.
* gdb.base/call-rt-st.exp: Likewise.
* gdb.base/call-sc.exp: Invoke gdb_skip_float_test and use its
return value instead of gdb,skip_float_test.
* gdb.base/callfuncs.exp: Invoke gdb_skip_float_test.
(do_function_calls): Use its return value instead of
gdb,skip_float_test.
* gdb.base/finish.exp: Likewise.
* gdb.base/funcargs.exp: Likewise.
* gdb.base/return.exp: Likewise.
* gdb.base/return2.exp: Likewise.
* gdb.base/varargs.exp: Likewise.
* lib/gdb.exp (gdb_skip_float_test): Change it to
gdb_caching_proc. Detect the broken ptrace on arm-linux.
This commit moves the target_wait prototype from the GDB-specific
target.h header to the common target/target.h header. Then, it
creates a compatible implementation of target_wait on gdbserver using
the_target->wait, and adjusts the (only) caller (mywait function).
Pretty straightforward, no regressions introduced.
gdb/gdbserver/ChangeLog:
2016-09-01 Sergio Durigan Junior <sergiodj@redhat.com>
* target.c (mywait): Call target_wait instead of
the_target->wait.
(target_wait): New function.
gdb/ChangeLog:
2016-09-01 Sergio Durigan Junior <sergiodj@redhat.com>
* target.c (target_wait): Mention that the function's prototype
can be found at target/target.h.
* target.h (target_wait): Move prototype from here...
* target/target.h (target_wait): ... to here.
This commit implements a new function, target_continue, on top of the
target_resume function. Then, it replaces all calls to target_resume
by calls to target_continue or to the already existing
target_continue_no_signal.
This is one of the (many) necessary steps needed to consolidate the
target interface between GDB and gdbserver. In particular, I am
interested in the impact this change will have on the unification of
the fork_inferior function (which I have been working on).
Tested on the BuildBot, no regressions introduced.
gdb/gdbserver/ChangeLog:
2016-09-31 Sergio Durigan Junior <sergiodj@redhat.com>
* server.c (start_inferior): New variable 'ptid'. Replace calls
to the_target->resume by target_continue{,_no_signal}, depending
on the case.
* target.c (target_stop_and_wait): Call target_continue_no_signal
instead of the_target->resume.
(target_continue): New function.
gdb/ChangeLog:
2016-09-31 Sergio Durigan Junior <sergiodj@redhat.com>
* fork-child.c (startup_inferior): Replace calls to target_resume
by target_continue{,_no_signal}, depending on the case.
* linux-nat.c (cleanup_target_stop): Call
target_continue_no_signal instead of target_resume.
* procfs.c (procfs_wait): Likewise.
* target.c (target_continue): New function.
* target/target.h (target_continue): New prototype.
bfd/
* elf32-arm.c (cmse_entry_fct_p): Store instruction encoding in an
array of bytes and use bfd_get_16 to interpret its encoding according
to endianness of target.
Fixes a gdb segfault if a section named .opd is found in ELFv2 binaries.
* elf64-ppc.c (synthetic_opd): New static var.
(compare_symbols): Don't treat symbols in .opd specially for ELFv2.
(ppc64_elf_get_synthetic_symtab): Likewise. Comment.
This patch fixes imbalanced lwp_suspend/unsuspend calls caused by the
premature choosing of another event for fairness.
select_event_lwp would switch the event before a call to
unsuspend_all_lwps, thus it would be called with the wrong event.
This caused an assertion failure: unsuspend LWP xx, suspended=-1 when
testing gdb.threads/non-stop-fair-events.exp with ARM range stepping in
GDBServer.
This patch moves the switch of event after the unsuspend/unstop calls.
No regressions, tested on ubuntu 14.04 ARMv7 and x86.
With gdbserver-native.
gdb/gdbserver/ChangeLog:
* linux-low.c (linux_wait_1): Move event switch after unsuspend_lwps.
This patch replaces "keep things single" with "keep things simple".
gdb:
2016-08-31 Yao Qi <yao.qi@linaro.org>
* record-full.c (record_full_insert_breakpoint): Fix typo.
This patch adds a little more debug output, and replaces two variables
with one, tracking current max group size by group_size_ rather than
by has14_.
* powerpc.cc (class Stub_control): Delete stub14_group_size_
and has14_. Add group_size_.
(Stub_control::can_add_to_stub_group): Adjust to suit. Print
debug info when switching to adding sections before stubs.
Like 57f6d32d, this patch ensures that sections containing external
conditional branches limit the group size.
* elf64-ppc.c (group_sections): Delete stub14_group_size. Instead,
track max group size with a new "group_size" var that is reduced
by a factor of 1024 from the 24-bit branch size whenever a 14-bit
branch is seen.
ELF section sh_flags SHF_PPC_VLE was being set based on arch/mach,
which meant all code sections in an object file has the flag or all
lacked it. We can do better than that. Only those code sections
where VLE is enabled ought to have the flag, allowing an object file
to contain both VLE and non-VLE code.
Also, ELF header p_flags PF_PPC_VLE wasn't being set, and segments
were being split unnecessarily.
bfd/
* elf32-ppc.c (ppc_elf_section_processing): Delete.
(elf_backend_section_processing): Don't define.
(ppc_elf_modify_segment_map): Set p_flags and mark valid. Don't
split on non-exec sections differing in SHF_PPC_VLE. When
splitting segments, mark size invalid.
gas/
* config/tc-ppc.c (md_assemble): Set sh_flags for VLE. Test
ppc_cpu rather than calling ppc_mach to determine VLE mode.
(ppc_frag_check, ppc_handle_align): Likewise use ppc_cpu.
Variable "header" in function is set conditionally, but was accessed without
verifying if pointer was NULL.
opcodes/ChangeLog:
Cupertino Miranda <cmiranda@synopsys.com>
* opcodes/arc-dis.c (print_insn_arc): Changed.
This inserts missing parentheses in the calculation of the comparison
result between two different inferior numbers. The problem was found by
Philipp Rudo.
gdb/ChangeLog:
* thread.c (tp_array_compar): Insert missing parentheses.
gdb/testsuite/ChangeLog:
* gdb.multi/tids.exp: Test "thread apply all".
ld/ChangeLog:
Cupertino Miranda <cmiranda@synopsys.com>
* testsuite/ld-arc/tls_gs-01.d: Set to XFAIL on arc*-*-elf*.
* testsuite/ld-arc/tls_ie-01.d: Likewise.
PR gprof/20499
* corefile.c (num_of_syms_in): Return an unsigned int.
Fail if the count exceeds the maximum possible allocatable size.
(core_create_syms_from): Exit early if num_of_syms_in returns a
failure code.
PR gprof/20499
* corefile.c (num_of_syms_in): Return an unsigned int.
(core_create_syms_from): Catch a possible integer overflow
computing the argument to xmalloc. Also allow for the possibility
that an integer overflow in num_of_syms_in means that less space
has been allocated than expected.
This patch rewrites the rather obscure can_add_to_stub_group, fixing
a problem with the handling of sections containing conditional
external branches. When a section group contains any such section,
the group size needs to be limited to a much smaller size than groups
with only non-conditional external branches.
PR 20523
* powerpc.cc (class Stub_control): Add has14_. Comment owner_.
(Stub_control::can_add_to_stub_group): Correct grouping of
sections containing 14-bit external branches. When returning
false, set state_ to reflect the fact that we have one section
for the next group. Rewrite most of function for clarity.
Add and expand comments.
(Target_powerpc::do_relax): Print stub group size retry in hex.
Since the internal compression header size can be bigger than the
external compression header size, we should check the external
compression header size.
* readelf.c (load_specific_debug_section): Check the external
compression header size.
On i386, IFUNC function must be called via PLT. Since PLT in PIC
object uses EBX register, R_386_PLT32 relocation must be used to
call IFUNC function even when IFUNC function is defined locally.
Linker should issue an error when R_386_PC32 relocation is used
to call IFUNC function.
Since PR ld/19784 tests doesn't use PLT relocation to local IFUNC
function, they are moved to the x86-64 test directory.
bfd/
PR ld/14961
PR ld/20515
* elf32-i386.c (elf_i386_check_relocs): Issue an error when
R_386_PC32 relocation is used to call IFUNC function in PIC
object.
ld/
PR ld/14961
PR ld/20515
* testsuite/ld-i386/i386.exp: Run pr20515.
* testsuite/ld-i386/pr20515.d: New file.
* testsuite/ld-i386/pr20515.s: Likewise.
* testsuite/ld-ifunc/ifunc-14a.s: Use R_386_PLT32 to call IFUNC
function.
* testsuite/ld-ifunc/ifunc-14c.s: Likewise.
* testsuite/ld-ifunc/ifunc-2-i386.s: Likewise.
* testsuite/ld-ifunc/ifunc-2-local-i386.s: Likewise.
* testsuite/ld-ifunc/ifunc.exp: Move PR ld/19784 tests to ...
* testsuite/ld-x86-64/x86-64.exp: Here.
* testsuite/ld-ifunc/pr19784a.c: Moved to ...
* testsuite/ld-x86-64/pr19784a.c: Here.
* testsuite/ld-ifunc/pr19784b.c: Moved to ...
* testsuite/ld-x86-64/pr19784b.c: Here.
* testsuite/ld-ifunc/pr19784c.c: Moved to ...
* testsuite/ld-x86-64/pr19784c.c: Here.
gold/ChangeLog
2016-08-26 Han Shen <shenhan@google.com>
* powerpc.cc (Stub_table::min_size_threshold_): New member to
limit size.
(Stub_table::set_min_size_threshold): New member function.
(Stub_table::set_address_and_size): Add code to only allow size
increase.
(Target_powerpc::do_relax): Add code to record last size.
Commit 980aa3e6 was supposed to cure dyn_reloc counting problems, but
did the opposite. For PIC we count two types of dyn_reloc, those on
pc-relative relocs, and the total. If a sym needs pc-relative dyn
relocs then all the relocs are dynamic. If not, then only those that
are must_be_dyn_reloc are dynamic.
PR 20519
* elf64-ppc.c (pc_dynrelocs): New function.
(ppc64_elf_relocate_section): Use it and must_be_dyn_reloc to
handle pic dynamic relocs.
This patch fixes a typo in the mnemonic of the camellia_fl
instruction, which was implemented before as camellia_fi.
gas/ChangeLog:
2016-08-26 Jose E. Marchesi <jose.marchesi@oracle.com>
* testsuite/gas/sparc/crypto.d: Rename invalid opcode camellia_fi
to camellia_fl.
* testsuite/gas/sparc/crypto.s: Likewise.
opcodes/ChangeLog:
2016-08-26 Jose E. Marchesi <jose.marchesi@oracle.com>
* sparc-opc.c (sparc_opcodes): Fix typo in opcode, camellia_fi ->
camellia_fl.
Nick Clifton
Senthil Kumar Selvaraj
GDB Administrator
Pedro Alves
Akash Trehan
Doug Kwan
Tom Tromey
H.J. Lu
Yao Qi
Sergio Durigan Junior
Thomas Preud'homme
Alan Modra
Antoine Tremblay
Cupertino Miranda
Andreas Arnez
Jan Kratochvil
Han Shen
Jose E. Marchesi