ada-lang.c has a "bound_name" static that is used when finding fields
in a structure in some cases. This patch removes it in favor of
computing the desired field name at runtime; this avoids an artificial
limit.
I'm checking this in. Tested on x86-64 Fedora 30, and also on the
internal AdaCore test suite.
gdb/ChangeLog
2020-05-20 Tom Tromey <tromey@adacore.com>
* ada-lang.c (bound_name, MAX_ADA_DIMENS): Remove.
(desc_one_bound, desc_index_type): Compute field name.
When running test-case gdb.base/with.exp with target board cc-with-gdb-index,
we have:
...
(gdb) PASS: gdb.base/with.exp: basics: show language
with language ada -- print g_s^M
'g_s' has unknown type; cast it to its declared type^M
(gdb) FAIL: gdb.base/with.exp: basics: with language ada -- print g_s
...
This is due to this bit in dw2_map_matching_symbols:
...
if (dwarf2_per_objfile->index_table != nullptr)
{
/* Ada currently doesn't support .gdb_index (see PR24713). We can get
here though if the current language is Ada for a non-Ada objfile
using GNU index. As Ada does not look for non-Ada symbols this
function should just return. */
return;
}
...
While the reasoning in the comment may be sound from language perspective, it
does introduce an inconsistency in gdb behaviour between:
- having a .gdb_index section, and
- having a .gdb_names section, or a partial symtab, or -readnow.
Fix the inconsistency by completing implementation of
dw2_map_matching_symbols.
Tested on x86_64-linux, both with native and target board
cc-with-debug-index.
gdb/ChangeLog:
2020-05-20 Tom de Vries <tdevries@suse.de>
PR symtab/25833
* dwarf2/read.c (dw2_map_matching_symbols): Handle .gdb_index.
gdb/testsuite/ChangeLog:
2020-05-20 Tom de Vries <tdevries@suse.de>
PR symtab/25833
* gdb.base/with-mf-inc.c: New test.
* gdb.base/with-mf-main.c: New test.
* gdb.base/with-mf.exp: New file.
ldmain.c:add_archive_element copies file name pointers from the bfd to
a lang_input_statement_type.
input->filename = abfd->filename;
input->local_sym_name = abfd->filename;
This results in stale pointers when twiddling the bfd filename in
places like the pe ld after_open. So don't free the bfd filename,
and make copies using bfd_alloc memory that won't result in small
memory leaks that annoy memory checkers.
PR 25993
bfd/
* archive.c (_bfd_get_elt_at_filepos): Don't strdup filename,
use bfd_set_filename.
* elfcode.h (_bfd_elf_bfd_from_remote_memory): Likewise.
* mach-o.c (bfd_mach_o_fat_member_init): Likewise.
* opncls.c (bfd_fopen, bfd_openstreamr, bfd_openr_iovec, bfd_openw),
(bfd_create): Likewise.
(_bfd_delete_bfd): Don't free filename.
(bfd_set_filename): Copy filename param to bfd_alloc'd memory,
return pointer to the copy or NULL on alloc fail.
* vms-lib.c (_bfd_vms_lib_get_module): Free newname and test
result of bfd_set_filename.
* bfd-in2.h: Regenerate.
gdb/
* solib-darwin.c (darwin_bfd_open): Don't strdup pathname for
bfd_set_filename.
* solib-aix.c (solib_aix_bfd_open): Use std::string for name
passed to bfd_set_filename.
* symfile-mem.c (add_vsyscall_page): Likewise for string
passed to symbol_file_add_from_memory.
(symbol_file_add_from_memory): Make name param a const char* and
don't strdup.
ld/
* emultempl/pe.em (gld_${EMULATION_NAME}_after_open): Don't copy
other_bfd_filename for bfd_set_filename, and test result of
bfd_set_filename call. Don't create a new is->filename, simply
copy from bfd filename. Free new_name after bfd_set_filename.
* emultempl/pep.em (gld_${EMULATION_NAME}_after_open): Likewise.
This patch makes gdb use the inline accessor for all bfd->filename
read accesses.
* coff-pe-read.c (read_pe_exported_syms): Use bfd_get_filename
rather than accessing bfd->filename directly.
* dtrace-probe.c (dtrace_static_probe_ops::get_probes): Likewise,
and use bfd_section_name.
* dwarf2/frame.c (decode_frame_entry): Likewise.
* exec.c (exec_set_section_address): Likewise.
* solib-aix.c (solib_aix_bfd_open): Likewise.
* stap-probe.c (get_stap_base_address): Likewise.
* symfile.c (reread_symbols): Likewise.
An earlier patch changed target_fileio_open, but missed a caller.
This patch fixes it.
2020-05-19 Tom Tromey <tromey@adacore.com>
* sparc64-tdep.c (adi_tag_fd): Update call to target_fileio_open.
Found by inspection, so I don't have a test for it (I don't think it
would be easy to have this bug cause a failure reliably).
We allocate space for N fields into `new_fields`, then memcpy N fields
at `new_fields + 1`. This overflows the allocated buffer by one field.
Fix it by allocating `N + 1` fields.
gdb/ChangeLog:
* dwarf2/read.c (quirk_rust_enum): Allocate enough fields.
The patch makes GDB do exec-file-mismatch validation by comparing
build IDs instead of the current method of comparing filenames.
Currently, the exec-file-mismatch feature simply compares filenames to
decide whether the exec file loaded in gdb and the exec file the
target reports is running match. This causes false positives when
remote debugging, because it'll often be the case that the paths in
the host and the target won't match. And of course misses the case of
the files having the same name but being actually different files
(e.g., different builds).
This also broke many testcases when running against gdbserver, causing
tests to be skipped like (here native-extended-gdbserver):
(gdb) run
Starting program: /home/pedro/gdb/binutils-gdb/build/gdb/testsuite/outputs/gdb.base/argv0-symlink/argv0-symlink-filelink
warning: Mismatch between current exec-file /home/pedro/gdb/binutils-gdb/build/gdb/testsuite/outputs/gdb.base/argv0-symlink/argv0-symlink-filelink
and automatically determined exec-file /home/pedro/gdb/binutils-gdb/build/gdb/testsuite/outputs/gdb.base/argv0-symlink/argv0-symlink
exec-file-mismatch handling is currently "ask"
Load new symbol table from "/home/pedro/gdb/binutils-gdb/build/gdb/testsuite/outputs/gdb.base/argv0-symlink/argv0-symlink"? (y or n) UNTESTED: gdb.base/argv0-symlink.exp: could not run to main
or to fail like (here native-gdbserver):
(gdb) spawn /home/pedro/gdb/binutils-gdb/build/gdb/testsuite/../../gdbserver/gdbserver --once localhost:2346 /home/pedro/gdb/binutils-gdb/build/gdb/te
stsuite/outputs/gdb.btrace/buffer-size/skip_btrace_tests-19968.x
Process /home/pedro/gdb/binutils-gdb/build/gdb/testsuite/outputs/gdb.btrace/buffer-size/skip_btrace_tests-19968.x created; pid = 20040
Listening on port 2346
target remote localhost:2346
Remote debugging using localhost:2346
warning: Mismatch between current exec-file /home/pedro/gdb/binutils-gdb/build/gdb/testsuite/temp/19968/skip_btrace_tests-19968.x
and automatically determined exec-file /home/pedro/gdb/binutils-gdb/build/gdb/testsuite/outputs/gdb.btrace/buffer-size/skip_btrace_tests-19968.x
exec-file-mismatch handling is currently "ask"
Load new symbol table from "/home/pedro/gdb/binutils-gdb/build/gdb/testsuite/outputs/gdb.btrace/buffer-size/skip_btrace_tests-19968.x"? (y or n) Quit
(gdb) UNSUPPORTED: gdb.btrace/buffer-size.exp: target does not support record-btrace
The former case is about GDB not realizing the two files are the same,
because one of the them is a symlink to the other. The latter case is
about GDB realizing that one file is a copy of the other.
Over the years, the toolchain has settled on build ID matching being
the canonical method to match core dumps to executables, and
executables with no debug info to their debug info.
This patch makes us use build IDs to match the running image of a
binary with its version loaded in gdb, which may or may not have debug
info. This is very much like the core dump/executable matching.
The change to gdb_bfd_open is necessary to get rid of the "transfers
from remote targets can be slow" warning when we open the remote file
to read its build ID:
(gdb) r
Starting program: /home/pedro/gdb/binutils-gdb/build/gdb/testsuite/outputs/gdb.base/break/break
Reading /home/pedro/gdb/binutils-gdb/build/gdb/testsuite/outputs/gdb.base/argv0-symlink/argv0-symlink from remote target...
warning: File transfers from remote targets can be slow. Use "set sysroot" to access files locally instead.
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
warning: Mismatch between current exec-file /home/pedro/gdb/binutils-gdb/build/gdb/testsuite/outputs/gdb.base/break/break
and automatically determined exec-file /home/pedro/gdb/binutils-gdb/build/gdb/testsuite/outputs/gdb.base/argv0-symlink/argv0-symlink
exec-file-mismatch handling is currently "ask"
Load new symbol table from "/home/pedro/gdb/binutils-gdb/build/gdb/testsuite/outputs/gdb.base/argv0-symlink/argv0-symlink"? (y or n)
While trying this out, I was worried that bfd would read a lot of
stuff from the binary in order to extract the build ID, making it
potentially slow, but turns out we don't read all that much. Maybe a
couple hundred bytes, and most of it seemingly is the read-ahead
cache. So I'm not worried about that. Otherwise I'd consider whether
a new qXfer:buildid:read would be better. But I'm happy that we
seemingly don't need to worry about it.
gdb/ChangeLog:
2020-05-19 Pedro Alves <palves@redhat.com>
* NEWS (set exec-file-mismatch): Adjust entry.
* exec.c: Include "build-id.h".
(validate_exec_file): Try to match build IDs instead of filenames.
* gdb_bfd.c (struct gdb_bfd_open_closure): New.
(gdb_bfd_iovec_fileio_open): Adjust to use gdb_bfd_open_closure
and pass down 'warn_if_slow'.
(gdb_bfd_open): Add 'warn_if_slow' parameter. Use
gdb_bfd_open_closure to pass it down.
* gdb_bfd.h (gdb_bfd_open): Add 'warn_if_slow' parameter.
gdb/doc/ChangeLog:
2020-05-19 Pedro Alves <palves@redhat.com>
* gdb.texinfo (Attach): Update exec-file-mismatch description to
mention build IDs.
(Separate Debug Files): Add "build id" anchor.
This basically makes target_fileio_open_1 extern, renamed to
target_fileio_open, and eliminates the current
target_fileio_open_warn_if_slow and target_fileio_open.
A following parameter will want to change gdb_bfd_iovec_fileio_open,
the only caller of target_fileio_open_warn_if_slow, to pass down
"warn_if_slow" true/false from the caller, instead of hardcoding
"warn_if_slow" true.
gdb/ChangeLog:
2020-05-19 Pedro Alves <palves@redhat.com>
* gdb_bfd.c (gdb_bfd_iovec_fileio_open): Adjust.
* target.c (target_fileio_open_1): Rename to target_fileio_open
and make extern. Use bool.
(target_fileio_open, target_fileio_open_warn_if_slow): Delete.
(target_fileio_read_alloc_1): Adjust.
* target.h (target_fileio_open): Add 'warn_if_slow' parameter.
(target_fileio_open_warn_if_slow): Delete declaration.
A following patch will add one more defaulted parameter.
gdb/ChangeLog:
2020-05-19 Pedro Alves <palves@redhat.com>
* gdb_bfd.h: (gdb_bfd_open): Default to 'fd' parameter to -1.
Adjust all callers.
Compiling with clang 11 gives us:
CXX h8300-tdep.o
/home/smarchi/src/binutils-gdb/gdb/h8300-tdep.c:225:21: error: overlapping comparisons always evaluate to false [-Werror,-Wtautological-overlap-compare]
if (disp < 0 && disp > 0xffffff)
~~~~~~~~~^~~~~~~~~~~~~~~~~~
/home/smarchi/src/binutils-gdb/gdb/h8300-tdep.c:203:17: error: overlapping comparisons always evaluate to false [-Werror,-Wtautological-overlap-compare]
if (disp < 0 && disp > 0xffffff)
~~~~~~~~~^~~~~~~~~~~~~~~~~~
/home/smarchi/src/binutils-gdb/gdb/h8300-tdep.c:184:17: error: overlapping comparisons always evaluate to false [-Werror,-Wtautological-overlap-compare]
if (disp < 0 && disp > 0xffffff)
~~~~~~~~~^~~~~~~~~~~~~~~~~~
Indeed, disp (of type LONGEST) can't be less than 0 and greater than
0xffffff.
Fix it by changing the way we check if disp is negative. Check the sign
bit of disp, which is a 24-bit number.
gdb/ChangeLog:
* h8300-tdep.c (h8300_is_argument_spill): Change how we check
whether disp is negative.
Change the symfile_segment_data::segment_info array to be an
std::vector. No functional changes are expected.
gdb/ChangeLog:
* symfile.h (struct symfile_segment_data)
<~symfile_segment_data>: Remove.
<segment_info>: Change to std::vector.
* symfile.c (default_symfile_segments): Update.
* elfread.c (elf_symfile_segments): Update.
Instead of maintaining two vectors, I added a small `segment` class
which holds both the base address and size of one segment and replaced
the two `segment_bases` and `segment_sizes` arrays with a single vector.
The rest of the changes are straightforward, no behavior changes are
expected.
gdb/ChangeLog:
* symfile.h (struct symfile_segment_data) <struct segment>: New.
<segments>: New.
<segment_bases, segment_sizes>: Remove.
* symfile.c (default_symfile_segments): Update.
* elfread.c (elf_symfile_segments): Update.
* remote.c (remote_target::get_offsets): Update.
* solib-target.c (solib_target_relocate_section_addresses):
Update.
- Allocate this structure with new instead of XNEW, use a unique pointer
to manage its lifetime.
- Change a few functions to return a unique pointer instead of a
plain pointer.
- Change free_symfile_segment_data to be symfile_segment_data's
destructor.
gdb/ChangeLog:
* symfile.h (struct symfile_segment_data): Initialize fields.
<~symfile_segment_data>: Add.
(symfile_segment_data_up): New.
(struct sym_fns) <sym_segments>: Return a
symfile_segment_data_up.
(default_symfile_segments): Return a symfile_segment_data_up.
(free_symfile_segment_data): Remove.
(get_symfile_segment_data): Return a symfile_segment_data_up.
* symfile.c (default_symfile_segments): Likewise.
(get_symfile_segment_data): Likewise.
(free_symfile_segment_data): Remove.
(symfile_find_segment_sections): Update.
* elfread.c (elf_symfile_segments): Return a
symfile_segment_data_up.
* remote.c (remote_target::get_offsets): Update.
* solib-target.c (solib_target_relocate_section_addresses):
Update.
* symfile-debug.c (debug_sym_segments): Return a
symfile_segment_data_up.
This is the 32-bit companion to
Remove unused ps_lgetLDT etc. on Solaris/x86 [PR25981]
https://sourceware.org/pipermail/gdb-patches/2020-May/168713.html
A 32-bit-default gdb fails to compile with the updated <sys/regset.h>.
While it is also affected by the lack of a GS definition, which the
compantion patch above fixes, it also fails to compile i386-sol2-nat.c like
this
/vol/src/gnu/gdb/hg/master/git/gdb/i386-sol2-nat.c:181:3: error: 'EAX' was not declared in this scope
181 | EAX, ECX, EDX, EBX,
| ^~~
and several more.
While this could be fixed by either including <ucontext.h> here or
provding fallback definitions of the register macros, I chose to do what
the 64-bit-default code in the same file
(amd64_sol2_gregset32_reg_offset[]) does, namely just hardcode the
numeric values instead. They are part of the ABI and thus guaranteed
not to change.
With this patch, a i386-pc-solaris2.11 configuration on master compiles
again, however, it doesn't work. However, I could successfully test it
on the gdb-9 branch.
Compiling and testing proved to be messy, unfortunately:
* For one, Solaris <sys/procfs.h> and largefile support used to be
mutually exclusive (fixed in Solaris 11.4 and Illumos), which was
exacerbated by the fact that g++ predefines _FILE_OFFSET_BITS=64 since
GCC 9.1.0. For now I've worked around this by adding
-U_FILE_OFFSET_BITS to CXXFLAGS and configuring with
--disable-largefile. I hope to clean this up in a future patch.
* gdb still defaults to startup-with-shell on. However, /bin/bash is a
64-bit executable which cannot be debugged by a 32-bit gdb. I hacked
around that part by pointing $SHELL at a 32-bit bash before running
make check.
PR build/25981
* i386-sol2-nat.c [PR_MODEL_NATIVE != PR_MODEL_LP64] (regmap):
Hardcode register numbers.
As reported in PR build/25981, a future Solaris 11.4 update will soon
remove the short i386 register names like SS etc. from <sys/regset.h>.
They could leak into user code (e.g. via <signal.h> -> <sys/signal.h> ->
<sys/ucontext.h>) and pollute the user namespace. Affected code would
have a hard time avoiding the issue: LLVM is one of those.
While the short names are required to be present by the i386 psABI, that
document only demands that they exist in <ucontext.h>, which is what the
upcoming update assures.
With this change, in a 64-bit-default configuration, procfs.c fails to
compile on Solaris/x86:
/vol/src/gnu/gdb/hg/master/git/gdb/procfs.c: In function 'ssd* procfs_find_LDT_entry(ptid_t)':
/vol/src/gnu/gdb/hg/master/git/gdb/procfs.c:1643:18: error: 'GS' was not declared in this scope
1643 | key = (*gregs)[GS] & 0xffff;
| ^~
make[2]: *** [Makefile:1607: procfs.o] Error 1
Initially I meant to provide a definition using the planned replacement
macro, but closer inspection revealed a better way. procfs_find_LDT_entry
and its helper proc_get_LDT_entry are only used to implement ps_lgetLDT,
one of the callback functions required by libthread_db.so.1
(cf. <proc_service.h>). While that function is still documented as being
required even in Solaris 11.4, I found that calls to it had been removed
long ago in Solaris 9, so just removing the three functions above is the
easiest fix.
The following patch does just that. It compiled successfully on
amd64-pc-solaris2.11, however, as reported in PR gdb/25939, master is
completely broken on Solaris since the multi-target patch. The patch
applies cleanly to the gdb-9 branch and there I could test it
successfully.
PR build/25981
* procfs.c [(__i386__ || __x86_64__) && sun] (proc_get_LDT_entry,
procfs_find_LDT_entry): Remove.
* procfs.h [(__i386__ || __x86_64__) && sun] (struct ssd,
procfs_find_LDT_entry): Remove.
* sol-thread.c [(__i386__ || __x86_64__) && sun] (ps_lgetLDT):
Remove.
In the following conditions:
- A target with hardware breakpoints available, and
- A target that uses software single stepping,
- An instruction at ADDRESS loops back to itself,
Now consider the following steps:
1. The user places a hardware breakpoint at ADDRESS (an instruction
that loops to itself),
2. The inferior runs and hits the breakpoint at ADDRESS,
3. The user tells GDB to 'continue'.
In #3 when the user tells GDB to continue, GDB first disables the
hardware breakpoint at ADDRESS, and then inserts a software
single-step breakpoint at ADDRESS. The original user-created
breakpoint was a hardware breakpoint, while the single-step breakpoint
will be a software breakpoint.
GDB continues and immediately hits the software single-step
breakpoint.
GDB then deletes the software single-step breakpoint by calling
delete_single_step_breakpoints, which eventually calls
delete_breakpoint, which, once the breakpoint (and its locations) are
deleted, calls update_global_location_list.
During update_global_location_list GDB spots that we have an old
location (the software single step breakpoint location) that is
inserted, but being deleted, and a location (the original hardware
breakpoint) at the same address which we are keeping, but which is not
currently inserted, GDB then calls breakpoint_locations_match on these
two locations.
Currently the locations do match, and so GDB calls swap_insertion
which swaps the "inserted" state of the two locations. The user
created hardware breakpoint is marked as inserted, while the GDB
internal software single step breakpoint is now marked as not
inserted. After this GDB returns through the call stack and leaves
delete_single_step_breakpoints.
After this GDB continues with its normal "stopping" process, as part
of this stopping process GDB removes all the breakpoints from the
target. Due to the swap it is now the user-created hardware
breakpoint that is marked as inserted, so it is this breakpoint GDB
tries to remove.
The problem is that GDB inserted the software single-step breakpoint
as a software breakpoint, but is now trying to remove the hardware
breakpoint. The problem is removing a software breakpoint is very
different to removing a hardware breakpoint, this could result is some
undetected undefined behaviour, or as in the original bug report (PR
gdb/25741), could result in the target throwing an error.
With "set breakpoint always-inserted on", we can easily reproduce this
against GDBserver. E.g.:
(gdb) hbreak main
Sending packet: $m400700,40#28...Packet received: 89e58b....
Sending packet: $m400736,1#fe...Packet received: 48
Hardware assisted breakpoint 1 at 0x400736: file threads.c, line 57.
Sending packet: $Z1,400736,1#48...Packet received: OK
Packet Z1 (hardware-breakpoint) is supported
(gdb) b main
Note: breakpoint 1 also set at pc 0x400736.
Sending packet: $m400736,1#fe...Packet received: 48
Breakpoint 2 at 0x400736: file threads.c, line 57.
(gdb) del
Delete all breakpoints? (y or n) y
Sending packet: $z0,400736,1#67...Packet received: E01
warning: Error removing breakpoint 2
This patch adds a testcase that does exactly that.
Trying to enhance GDB to handle this scenario while continuing to
avoid inserting redundant software and hardware breakpoints at the
same address turns out futile, because, given non-stop and breakpoints
always-inserted, if the user:
#1 - inserts a hw breakpoint, then
#2 - inserts a sw breakpoint at the same address, and then
#3 - removes the original hw breakpoint,
GDB would have to make sure to insert the sw breakpoint before
removing the hw breakpoint, to avoid running threads missing the
breakpoint. I.e., there's always going to be a window where a target
needs to be able to handle both sw and a hw breakpoints installed at
the same address. You can see more detailed description of that issue
here:
https://sourceware.org/pipermail/gdb-patches/2020-April/167738.html
So the fix here is to just stop considering software breakpoints and
hw breakpoints duplicates, and let GDB insert sw and hw breakpoints at
the same address.
The central change is to make breakpoint_locations_match consider the
location's type too. There are several other changes necessary to
actually make that that work correctly, however:
- We need to handle the duplicates detection better. Take a look at
the loop at the tail end of update_global_location_list. Currently,
because breakpoint locations aren't sorted by type, we can end up
with, at the same address, a sw break, then a hw break, then a sw
break, etc. The result is that that second sw break won't be
considered a duplicate of the first sw break. Seems like we already
handle that incorrectly for range breakpoints.
- The "set breakpoint auto-hw on" handling is moved out of
insert_bp_location to update_global_location_list, before the
duplicates determination.
Moving "set breakpoint auto-hw off" handling as well and downgrading
it to a warning+'disabling the location' was considered too, but in
the end discarded, because we want to error out with internal and
momentary breakpoints, like software single-step breakpoints.
Disabling such locations at update_global_location_list time would
make GDB lose control of the inferior.
- In update_breakpoint_locations, the logic of matching old locations
with new locations, in the have_ambiguous_names case, is updated to
still consider sw vs hw locations the same.
- Review all ALL_BP_LOCATIONS_AT_ADDR uses, and update those that
might need to be updated, and update comments for those that don't.
Note that that macro walks all locations at a given address, and
doesn't call breakpoint_locations_match.
The result against GDBserver (with "set breakpoint
condition-evaluation host" to avoid seeing confusing reinsertions) is:
(gdb) hbreak main
Sending packet: $m400736,1#fe...Packet received: 48
Hardware assisted breakpoint 1 at 0x400736: file main.c, line 57.
Sending packet: $Z1,400736,1#48...Packet received: OK
(gdb) b main
Note: breakpoint 1 also set at pc 0x400736.
Sending packet: $m400736,1#fe...Packet received: 48
Breakpoint 4 at 0x400736: file main.c, line 57.
Sending packet: $Z0,400736,1#47...Packet received: OK
(gdb) del 3
Sending packet: $z1,400736,1#68...Packet received: OK
gdb/ChangeLog:
2020-05-17 Pedro Alves <palves@redhat.com>
Andrew Burgess <andrew.burgess@embecosm.com>
Keno Fischer <keno@juliacomputing.com>
PR gdb/25741
* breakpoint.c (build_target_condition_list): Update comments.
(build_target_command_list): Update comments and skip matching
locations.
(insert_bp_location): Move "set breakpoint auto-hw on" handling to
a separate function. Simplify "set breakpoint auto-hw off"
handling.
(insert_breakpoints): Update comment.
(tracepoint_locations_match): New parameter. For breakpoints,
compare location types too, if the caller wants to.
(handle_automatic_hardware_breakpoints): New functions.
(bp_location_is_less_than): Also sort by location type and
hardware breakpoint length.
(update_global_location_list): Handle "set breakpoint auto-hw on"
here.
(update_breakpoint_locations): Ask breakpoint_locations_match to
ignore location types.
gdb/testsuite/ChangeLog:
2020-05-17 Pedro Alves <palves@redhat.com>
PR gdb/25741
* gdb.base/hw-sw-break-same-address.exp: New file.
Remove `TYPE_NAME`, changing all the call sites to use `type::name`
directly. This is quite a big diff, but this was mostly done using sed
and coccinelle. A few call sites were done by hand.
gdb/ChangeLog:
* gdbtypes.h (TYPE_NAME): Remove. Change all cal sites to use
type::name instead.
Add the `name` and `set_name` methods on `struct type`, in order to
remove the `TYPE_NAME` macro. In this patch, the `TYPE_NAME` macro is
changed to use `type::name`, so all the call sites that are used to set
the type name are changed to use `type::set_name`. The next patch will
remove `TYPE_NAME` completely.
gdb/ChangeLog:
* gdbtypes.h (struct type) <name, set_name>: New methods.
(TYPE_CODE): Use type::name. Change all call sites used to set
the name to use type::set_name instead.
Continuing my goal of removing the "ALL_*" iterator macros, this
removes ALL_UIS, replacing it with an iterator adaptor.
gdb/ChangeLog
2020-05-16 Tom Tromey <tom@tromey.com>
* top.c (quit_force): Update.
* infrun.c (handle_no_resumed): Update.
* top.h (all_uis): New function.
(ALL_UIS): Remove.
When building with clang 11, I get:
CXX mips-linux-tdep.o
/home/smarchi/src/binutils-gdb/gdb/mips-linux-tdep.c:643:30: error: overlapping comparisons always evaluate to true [-Werror,-Wtautological-overlap-compare]
if (insn != 0x03e07821 || insn != 0x03e07825)
~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
/home/smarchi/src/binutils-gdb/gdb/mips-linux-tdep.c:636:30: error: overlapping comparisons always evaluate to true [-Werror,-Wtautological-overlap-compare]
if (insn != 0x03e0782d || insn != 0x03e07825)
~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~
Indeed, given two different values, `insn` will always be different to
one of them, and these conditions always be true.
This code is meant to return if `insn` isn't one of these two values, so
the `||` should be replaced with `&&`.
gdb/ChangeLog:
* mips-linux-tdep.c (mips_linux_in_dynsym_stub): Fix condition.
This commit should fix:
../../gdb/ia64-linux-nat.c: In function ‘void enable_watchpoints_in_psr(ptid_t)’:
../../gdb/ia64-linux-nat.c:535:56: error: no matching function for call to ‘get_thread_regcache(ptid_t&)’
struct regcache *regcache = get_thread_regcache (ptid);
^
In file included from ../../gdb/ia64-linux-nat.c:25:0:
../../gdb/regcache.h:35:25: note: candidate: regcache* get_thread_regcache(process_stratum_target*, ptid_t)
extern struct regcache *get_thread_regcache (process_stratum_target *target,
^
../../gdb/regcache.h:35:25: note: candidate expects 2 arguments, 1 provided
../../gdb/regcache.h:39:25: note: candidate: regcache* get_thread_regcache(thread_info*)
extern struct regcache *get_thread_regcache (thread_info *thread);
^
../../gdb/regcache.h:39:25: note: no known conversion for argument 1 from ‘ptid_t’ to ‘thread_info*’
gdb/ChangeLog:
2020-05-16 Pedro Alves <palves@redhat.com>
* ia64-linux-nat.c
(ia64_linux_nat_target) <enable_watchpoints_in_psr(ptid_t)>:
Declare method.
(enable_watchpoints_in_psr): Now a method of ia64_linux_nat_target.
When building with clang 11, I get:
CXX sparc64-tdep.o
/home/smarchi/src/binutils-gdb/gdb/sparc64-tdep.c:89:15: error: anonymous non-C-compatible type given name for linkage purposes by typedef declaration; add a tag name here [-Werror,-Wnon-c-typedef-for-linkage]
typedef struct
^
adi_stat_t
/home/smarchi/src/binutils-gdb/gdb/sparc64-tdep.c:103:16: note: type is not C-compatible due to this default member initializer
int tag_fd = 0;
^
/home/smarchi/src/binutils-gdb/gdb/sparc64-tdep.c:111:3: note: type is given name 'adi_stat_t' for linkage purposes by this typedef declaration
} adi_stat_t;
^
The typedef is not needed in C++ anyway, just remove them.
gdb/ChangeLog:
* sparc64-tdep.c (adi_stat_t): Remove typedef (leaving struct).
(sparc64_adi_info): Likewise.
lookup_objfile_from_block mostly duplicates the functionality of
block_objfile, but in a less efficient way. This patch removes this
function and changes the callers to use block_objfile instead.
Tested by the buildbot.
gdb/ChangeLog
2020-05-15 Tom Tromey <tom@tromey.com>
* symtab.c (lookup_language_this, lookup_symbol_aux): Use
block_objfile.
(lookup_objfile_from_block): Remove.
(lookup_symbol_in_block, lookup_symbol_in_static_block)
(lookup_global_symbol): Use block_objfile.
* symtab.h (lookup_objfile_from_block): Don't declare.
* printcmd.c (clear_dangling_display_expressions): Use
block_objfile.
* parse.c (operator_check_standard): Use block_objfile.
gdb/ChangeLog
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* NEWS: Mention changes to help and apropos.
gdb/doc/ChangeLog
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* gdb.texinfo (Help): Document the help and apropos changes.
(Aliases): Document new meaning of -a abbreviation flag.
This commit finally does the (small) change that started this patch
series.
It ensures that the class_alias is only used for user-defined aliases.
So, the few GDB pre-defined aliases that were using the 'class_alias'
class are now using a real help class, typically the class of
the aliased command.
gdb/ChangeLog
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* command.h (enum command_class): Improve comments, document
that class_alias is for user-defined aliases, give the class
name for each class, remove unused class_xdb.
* cli/cli-decode.c (add_com_alias): Document THECLASS intended usage.
* breakpoint.c (_initialize_breakpoint): Replace class_alias
by a precise class.
* infcmd.c (_initialize_infcmd): Likewise.
* reverse.c (_initialize_reverse): Likewise.
* stack.c (_initialize_stack): Likewise.
* symfile.c (_initialize_symfile): Likewise.
* tracepoint.c (_initialize_tracepoint): Likewise.
gdb/testsuite/ChangeLog
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* gdb.base/alias.exp: Verify 'help aliases' shows user defined aliases.
Similarly to 'help CLASS', apropos possibly shows several
times the same help (for the command and for each of its aliases).
This patch changes 'apropos' so that the help for a command and
all its aliases is shown once.
So, apropos_cmd now skips all aliases/abbreviations, as these are printed
as part of the help of the aliased command.
When 'apropos' prints the help of a command, function 'help_cmd' now
unconditionally print the command name and its possible aliases (as we must
indicate to the user the command/aliases for which the help is printed).
When 'help somecommand' prints the help of a command, if the command is not
aliased, the command name is not printed (to avoid a useless first line), but if
it has aliases, then the command name and all its aliases are now printed.
In addition to provide to the user the choice of the best way to
type a command, it also avoids the strange behaviour that the output
of 'help somealias' does not mention somealias.
gdb/ChangeLog
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* cli/cli-decode.c (apropos_cmd): Produce output for aliases
when their aliased command is traversed.
(help_cmd): Add fput_command_names_styled call to
output command name and aliases when command has an alias.
gdb/testsuite/ChangeLog
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* gdb.base/help.exp: Test apropos and help for commands
having aliases. Fixed comments not starting with an
upper-case letter or not finishing with a dot.
Currently, help CLASS possibly shows several times the same help,
as it shows it once for the command, and once for each alias.
The final objective of this patch series is to have class_alias used only
for user defined aliases, not anymore for aliases predefined by GDB.
The command 'help aliases' will then only show the user defined aliases.
So, the idea is that GDB predefined aliases will be shown together
with their aliased command.
This commit changes 'help CLASS' so that a command is shown once in the output,
with all its aliases.
This ensures:
* that the user has only to read once the same help text
* and sees the command and all its aliases in a glance, a.o. allowing
the user to choose the preferred way (e.g. the shortest one,
or the most mnemonic one) to type the command.
For example, the old output:
(gdb) help stack
...
List of commands:
backtrace -- Print backtrace of all stack frames, or innermost COUNT frames.
bt -- Print backtrace of all stack frames, or innermost COUNT frames.
...
(note that 'where' is not shown in this output)
becomes
(gdb) help stack
...
List of commands:
backtrace, where, bt -- Print backtrace of all stack frames, or innermost COUNT frames.
...
The output layout chosen is to have the command first, followed by all its
aliases separated by a comma. Note that the command and alias names are
title-styled. For sure, other layouts could be discussed, but this one is IMO
readable and compact.
The function 'help_cmd_list' can be simplified by removing the prefix argument,
as the prefixname of a command can now be retrieved in the GDB command tree
structure.
This also fixes the fact that 'help aliases' wrongly shows a long
list of (non-alias) when defining an alias for a prefix command.
For example, after:
(gdb) alias montre = show
then
(gdb) help aliases
shows hundreds of sub-commands starting with the non aliased command,
such as:
montre -- Generic command for showing things about the debugger.
show ada -- Generic command for showing Ada-specific settings.
show ada print-signatures -- Show whether the output of formal ...
....
'help_cmd_list' is also made static, as it is only used inside cli-decode.c.
Note that the 'help CLASS' is somewhat broken, in the sense that it
sometimes shows too many commands (commands not belonging to CLASS)
and sometimes shows not enough commands (not showing some commands
belonging to CLASS).
For example, 'help breakpoints' shows the command
'disable pretty-printer' and 'disable unwinder', not related to breakpoints.
On the other end, 'help stack' does not show 'disable unwinder'
while 'disable unwinder' is defined in unwinders.py as belonging to class_stack.
Fixing the missing commands is easy to do,
but fixing the excess commands is not straightforward, as many
subcommands have a class 'no_class' or 'all_class'.
Possibly, some of this might be improved/fixed in another patch series.
With this patch series, the 'abbrev flag' has as only remaining purpose
to avoid having the abbreviation alias appearing in the completion list,
so change 'help alias' accordingly.
gdb/ChangeLog
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* cli/cli-decode.h (help_cmd_list): Remove declaration.
* cli/cli-decode.c (help_cmd_list): Declare as static,
remove prefix argument, use bool for recurse arg, rework to show the aliases of
a command together with the command.
(fput_command_name_styled, fput_command_names_styled): New functions.
(print_help_for_command): Remove prefix arg, use bool for recurse arg, use
fput_command_name_styled.
(help_list, help_all): Update callers to remove prefix arg and use bool recurse.
* cli/cli-cmds.c (_initialize_cli_cmds): Update alias_command doc.
gdb/testsuite/ChangeLog
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* gdb.base/alias.exp: Update help output check.
cmd_show_list function implements the 'show' command.
cmd_show_list output is inconsistent: it sometimes shows a prefix
and sometimes does not.
For example, in the below, you see that there is a prefix before
each value, except for 'enabled'.
(gdb) show style
style address background: The "address" style background color is: none
style address foreground: The "address" style foreground color is: blue
style address intensity: The "address" style display intensity is: normal
enabled: CLI output styling is enabled.
style filename background: The "filename" style background color is: none
...
There are other inconsistencies or bugs e.g. in
the below we see twice insn-number-max, once with a prefix
and once without prefix : last line, just before the value of
instruction-history-size which is itself without prefix.
(gdb) show record
record btrace bts buffer-size: The record/replay bts buffer size is 65536.
record btrace cpu: btrace cpu is 'auto'.
record btrace pt buffer-size: The record/replay pt buffer size is 16384.
record btrace replay-memory-access: Replay memory access is read-only.
record full insn-number-max: Record/replay buffer limit is 200000.
record full memory-query: Whether query if PREC cannot record memory change of next instruction is off.
record full stop-at-limit: Whether record/replay stops when record/replay buffer becomes full is on.
function-call-history-size: Number of functions to print in "record function-call-history" is 10.
insn-number-max: instruction-history-size: Number of instructions to print in "record instruction-history" is 10.
(gdb)
Also, some values are output several times due to some aliases, so avoid outputting duplicated
values by skipping all aliases.
Now that the command structure has a correct 'back-pointer' from a command
to its prefix command, we can simplify cmd_show_list by removing its prefix argument
and at the same time fix the output inconsistencies and bugs.
gdb/ChangeLog
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* cli/cli-setshow.h (cmd_show_list): Remove prefix argument.
* cli/cli-decode.c (do_show_prefix_cmd): Likewise.
* command.h (cmd_show_list): Likewise.
* dwarf2/index-cache.c (show_index_cache_command): Likewise.
* cli/cli-setshow.c (cmd_show_list): Use the prefix to produce the output. Skip aliases.
gdb/testsuite/ChangeLog
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* gdb.base/default.exp: Update output following fixes.
This test revealed a number of problems that are fixed in the previous commit.
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* unittests/command-def-selftests.c (traverse_command_structure):
Verify all commands of a list have the same prefix command and
that only the top cmdlist commands have a null prefix.
The next commit updates command-def-selftests.c to detect missing
or wrong prefix commands in a list of subcommands.
This command structure selftest detects a series of problems
that are fixed by this commit.
Many commands have a null prefix command, e.g.
(gdb) maintenance selftest command_str
Running selftest command_structure_invariants.
list 0x560417949cb8 reachable via prefix 'append binary '. command 'memory' has null prefixcmd
list 0x560417949cb8 reachable via prefix 'append binary '. command 'value' has null prefixcmd
...
Most of these are fixed by the following changes:
* do_add_cmd searches the prefix command having the list
in which the command is added.
This ensures that a command defined after its prefix command
gets the correct prefix command.
* Due to the GDB initialization order, a GDB file can define
a subcommand before the prefix command is defined.
So, have add_prefix_cmd calling a new recursive function
'update_prefix_field_of_prefix_commands' to set the prefix
command of all sub-commands that are now reachable from
this newly defined prefix command. Note that this recursive
call replaces the function 'set_prefix_cmd' that was providing
a partial solution to this problem.
Following that, 2 python commands (defined after all the other GDB
commands) got a wrong prefix command, e.g. "info frame-filter" has
as prefix command the "i" alias of "info". This is fixed by having
lookup_cmd_for_prefixlist returning the aliased command rather than
the alias.
After that, one remaining problem:
(gdb) maintenance selftest command_str
Running selftest command_structure_invariants.
list 0x55f320272298 reachable via prefix 'set remote '. command 'system-call-allowed' has null prefixcmd
Self test failed: self-test failed at ../../classfix/gdb/unittests/command-def-selftests.c:196
Ran 1 unit tests, 1 failed
(gdb)
Caused by initialize_remote_fileio that was taking the address of
its arguments remote_set_cmdlist and remote_show_cmdlist instead
of receiving the correct values to use as list.
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* cli/cli-decode.c (lookup_cmd_for_prefix): Return the aliased command
as prefix, not one of its aliases.
(set_cmd_prefix): Remove.
(do_add_cmd): Centralize the setting of the prefix of a command, when
command is defined after its full chain of prefix commands.
(add_alias_cmd): Remove call to set_cmd_prefix, as do_add_cmd does it.
(add_setshow_cmd_full): Likewise.
(update_prefix_field_of_prefixed_commands): New function.
(add_prefix_cmd): Replace non working call to set_cmd_prefix by
update_prefix_field_of_prefixed_commands.
* gdb/remote-fileio.c (initialize_remote_fileio): Use the real
addresses of remote_set_cmdlist and remote_show_cmdlist given
as argument, not the address of an argument.
* gdb/remote-fileio.h (initialize_remote_fileio): Likewise.
* gdb/remote.c (_initialize_remote): Likewise.
When an alias name starts with the name of another alias,
GDB was accepting to define the aliases in one order (short first, long after),
but refused it the other way around.
So, fix the logic to recognise an already existing alias by using
lookup_cmd_composition.
Also, this revealed a bug in lookup_cmd_composition:
when the searched command is a prefix command, lookup_cmd_composition
was not returning the fact that a command was found even if the
TEXT to parse was fully consumed.
gdb/ChangeLog
YYYY-MM-DD Philippe Waroquiers <philippe.waroquiers@skynet.be>
* cli/cli-cmds.c (alias_command): Check for an existing alias
using lookup_cmd_composition, as valid_command_p is too strict
and forbids aliases that are the prefix of an existing alias
or command.
* cli/cli-decode.c (lookup_cmd_composition): Ensure a prefix
command is properly recognised as a valid command.
gdb/testsuite/ChangeLog
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* gdb.base/alias.exp: Test aliases starting with a prefix of
another alias.
The GDB data structure that records the GDB commands is made of
'struct cmd_list_element' defined in cli-decode.h.
A cmd_list_element has various pointers to other cmd_list_element structures,
All these pointers are together building a graph of commands.
However, when following the 'next' and '*prefixlist' pointers of
cmd_list_element, the structure must better be a tree.
If such pointers do not form a tree, then some other elements of
cmd_list_element cannot get a correct semantic. In particular, the prefixname
has no correct meaning if the same prefix command can be reached via 2 different
paths.
This commit introduces a selftest that detects (at least some cases of) errors
leading to 'next' and '*prefixlist' not giving a tree structure.
The new 'command_structure_invariants' selftest detects one single case where
the command structure is not a tree:
(gdb) maintenance selftest command_structure_invariants
Running selftest command_structure_invariants.
list 0x56362e204b98 duplicated, reachable via prefix 'show ' and 'info set '. Duplicated list first command is 'ada'
Self test failed: self-test failed at ../../classfix/gdb/unittests/command-def-selftests.c:160
Ran 1 unit tests, 1 failed
(gdb)
This was fixed by the previous commit.
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* unittests/help-doc-selftests.c: Rename to
unittests/command-def-selftests.c
* unittests/command-def-selftests.c (help_doc_tests): Update some
comments.
(command_structure_tests, traverse_command_structure): New namespace
and function.
(command_structure_invariants_tests): New function.
(_initialize_command_def_selftests) Renamed from
_initialize_help_doc_selftests, register command_structure_invariants
selftest.
The next commit introduces a selftest that detects when the GDB
command structure does not define a tree when using the pointers
'next/*prefixlist'. This test detects one such case, fixed
by this commit.
The command 'info set' was defined as a specific prefix command,
but re-using the command list already used for the 'show' command.
This leads to the command tree 'next/*prefixlist' to not be a tree.
This change defines 'info set ' as an alias, thereby fixing the selftest.
2020-05-15 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* cli/cli-cmds.c (_initialize_cli_cmds): Define 'info set' as
an alias of 'show'.
The purpose of this patch is to prepare for the future where
fixed point types become described using standard DWARF info,
rather than GNAT encodings. For that, we rename a number of
routines manipulating Ada fixed point types to make it explicit
from their new names that they rely on the GNAT encodings to work.
This will allow us, when we introduce support for fixed point types
from standard DWARF to use names that are not ambiguous with
the functions that do similar work, but only for GNAT encodings.
gdb/ChangeLog:
* ada-lang.h: (ada_is_gnat_encoded_fixed_point_type): Renames
ada_is_fixed_point_type. Update all callers.
(gnat_encoded_fixed_point_delta): Renames ada_delta. Update
all callers.
* ada-lang.c (gnat_encoded_fixed_type_info): Renames fixed_type_info.
Update all callers.
* ada-typeprint.c (print_gnat_encoded_fixed_point_type): Renames
print_fixed_point_type. Update all callers.
* ada-valprint.c (ada_value_print_num): Replace call to
ada_is_fixed_point_type by ada_is_gnat_encoded_fixed_point_type.
Some Intel processors implement a Branch Trace Store (BTS) which GDB
uses for reverse execution support via the "record btrace bts"
command.
I have been unable to find a description of a similar feature in a
recent (April 2020) AMD64 architecture reference:
https://www.amd.com/system/files/TechDocs/40332.pdf
While it is the case that AMD processors have an LBR (last branch
record) bit in the DebugCtl MSR, it seems that it affects only four
MSRs when enabled. The names of these MSRs are LastBranchToIP,
LastBranchFromIP, LastIntToIP, and LastIntFromIP. I can find no
mention of anything more extensive. While looking at an Intel
architecture document, I noticed that Intel's P6 family from the
mid-90s had registers of the same name.
Therefore...
This commit disables "record btrace bts" support in GDB for AMD
processors.
Using the test case from gdb.base/break.exp, the sessions
below show the expected behavior (run on a machine with an
Intel processor) versus that on a machine with an AMD processor.
The AMD processor in question is reported as follows by "lscpu":
AMD Ryzen Threadripper 2950X 16-Core Processor . Finally, I'll
note that the AMD machine is actually a VM, but I see similar
behavior on both the virtualization host and the VM.
Intel machine - Desired behavior:
[kevinb@mohave gdb]$ ./gdb -q testsuite/outputs/gdb.base/break/break
Reading symbols from testsuite/outputs/gdb.base/break/break...
(gdb) start
Temporary breakpoint 1 at 0x401179: file /home/kevinb/sourceware-git/native-build/bld/../../binutils-gdb/gdb/testsuite/gdb.base/break.c, line 43.
Starting program: /home/kevinb/sourceware-git/native-build/bld/gdb/testsuite/outputs/gdb.base/break/break
Temporary breakpoint 1, main (argc=1, argv=0x7fffffffd748, envp=0x7fffffffd758)
at /home/kevinb/sourceware-git/native-build/bld/../../binutils-gdb/gdb/testsuite/gdb.base/break.c:43
43 if (argc == 12345) { /* an unlikely value < 2^16, in case uninited */ /* set breakpoint 6 here */
(gdb) record btrace
(gdb) b factorial
Breakpoint 2 at 0x40121b: file /home/kevinb/sourceware-git/native-build/bld/../../binutils-gdb/gdb/testsuite/gdb.base/break.c, line 63.
(gdb) c
Continuing.
Breakpoint 2, factorial (value=6)
at /home/kevinb/sourceware-git/native-build/bld/../../binutils-gdb/gdb/testsuite/gdb.base/break.c:63
63 if (value > 1) { /* set breakpoint 7 here */
(gdb) info record
Active record target: record-btrace
Recording format: Branch Trace Store.
Buffer size: 64kB.
Recorded 768 instructions in 22 functions (0 gaps) for thread 1 (process 19215).
(gdb) record function-call-history
13 do_lookup_x
14 _dl_lookup_symbol_x
15 _dl_fixup
16 _dl_runtime_resolve_xsavec
17 atoi
18 strtoq
19 ____strtoll_l_internal
20 atoi
21 main
22 factorial
(gdb) record instruction-history
759 0x00007ffff7ce0917 <____strtoll_l_internal+647>: pop %r15
760 0x00007ffff7ce0919 <____strtoll_l_internal+649>: retq
761 0x00007ffff7cdd064 <atoi+20>: add $0x8,%rsp
762 0x00007ffff7cdd068 <atoi+24>: retq
763 0x00000000004011b1 <main+75>: mov %eax,%edi
764 0x00000000004011b3 <main+77>: callq 0x401210 <factorial>
765 0x0000000000401210 <factorial+0>: push %rbp
766 0x0000000000401211 <factorial+1>: mov %rsp,%rbp
767 0x0000000000401214 <factorial+4>: sub $0x10,%rsp
768 0x0000000000401218 <factorial+8>: mov %edi,-0x4(%rbp)
AMD machine - Wrong behavior:
[kev@f32-1 gdb]$ ./gdb -q testsuite/outputs/gdb.base/break/break
Reading symbols from testsuite/outputs/gdb.base/break/break...
(gdb) start
Temporary breakpoint 1 at 0x401179: file /ironwood1/sourceware-git/f32-master/bld/../../worktree-master/gdb/testsuite/gdb.base/break.c, line 43.
Starting program: /mesquite2/sourceware-git/f32-master/bld/gdb/testsuite/outputs/gdb.base/break/break
Temporary breakpoint 1, main (argc=1, argv=0x7fffffffd5b8, envp=0x7fffffffd5c8)
at /ironwood1/sourceware-git/f32-master/bld/../../worktree-master/gdb/testsuite/gdb.base/break.c:43
43 if (argc == 12345) { /* an unlikely value < 2^16, in case uninited */ /* set breakpoint 6 here */
(gdb) record btrace
(gdb) b factorial
Breakpoint 2 at 0x40121b: file /ironwood1/sourceware-git/f32-master/bld/../../worktree-master/gdb/testsuite/gdb.base/break.c, line 63.
(gdb) c
Continuing.
Breakpoint 2, factorial (value=6)
at /ironwood1/sourceware-git/f32-master/bld/../../worktree-master/gdb/testsuite/gdb.base/break.c:63
63 if (value > 1) { /* set breakpoint 7 here */
(gdb) info record
Active record target: record-btrace
Recording format: Branch Trace Store.
Buffer size: 64kB.
warning: Recorded trace may be incomplete at instruction 7737 (pc = 0x405000).
warning: Recorded trace may be incomplete at instruction 7739 (pc = 0x0).
Recorded 7740 instructions in 46 functions (2 gaps) for thread 1 (process 1402911).
(gdb) record function-call-history
37 ??
38 values
39 some_enum_global
40 ??
41 some_union_global
42 some_variable
43 ??
44 [decode error (2): unknown instruction]
45 ??
46 [decode error (2): unknown instruction]
(gdb) record instruction-history
7730 0x0000000000404ff3: add %al,(%rax)
7731 0x0000000000404ff5: add %al,(%rax)
7732 0x0000000000404ff7: add %al,(%rax)
7733 0x0000000000404ff9: add %al,(%rax)
7734 0x0000000000404ffb: add %al,(%rax)
7735 0x0000000000404ffd: add %al,(%rax)
7736 0x0000000000404fff: .byte 0x0
7737 0x0000000000405000: Cannot access memory at address 0x405000
Lastly, I'll note that I see a lot of gdb.btrace failures without
this commit. Worse still, the results aren't always the same which
causes a lot of noise when comparing test results.
gdbsupport/ChangeLog:
* btrace-common.h (btrace_cpu_vendor): Add CV_AMD.
gdb/ChangeLog:
* nat/linux-btrace.c (btrace_this_cpu): Add check for AMD
processors.
(cpu_supports_bts): Add CV_AMD case.
[Simon: I send this patch on behalf of Laurent Morichetti, I added the
commit message and performance measurement stuff.
Also, this patch is better viewed with "git show -w".]
stop_all_threads, in infrun.c, is used to stop all running threads on
targets that are always non-stop. It's used, for example, when the
program hits a breakpoint while GDB is set to "non-stop off". It sends
a stop request for each running thread, then collects one wait event for
each.
Since new threads can spawn while we are stopping the threads, it's
written in a way where it makes multiple such "send stop requests to
running threads & collect wait events" passes. The function completes
when it has made two passes where it hasn't seen any running threads.
With the way it's written right now is, it iterates on the thread list,
sending a stop request for each running thread. It then waits for a
single event, after which it iterates through the thread list again. It
sends stop requests for any running threads that's been created since
the last iteration. It then consumes another single wait event.
This makes it so we iterate on O(n^2) threads in total, where n is the
number of threads. This patch changes the function to reduce it to
O(n). This starts to have an impact when dealing with multiple
thousands of threads (see numbers below). At each pass, we know the
number of outstanding stop requests we have sent, for which we need to
collect a stop event. We can therefore loop to collect this many stop
events before proceeding to the next pass and iterate on the thread list
again.
To check the performance improvements with this patch, I made an
x86/Linux program with a large number of idle threads (varying from 1000
to 10000). The program's main thread hits a breakpoint once all these
threads have started, which causes stop_all_threads to be called to stop
all these threads. I measured (by patching stop_all_threads):
- the execution time of stop_all_threads
- the total number of threads we iterate on during the complete
execution of the function (the total number of times we execute the
"for (thread_info *t : all_non_exited_threads ())" loop)
These are the execution times, in milliseconds:
# threads before after
1000 226 106
2000 997 919
3000 3461 2323
4000 4330 3570
5000 8642 6600
6000 9918 8039
7000 12662 10930
8000 16652 11222
9000 21561 15875
10000 26613 20019
Note that I very unscientifically executed each case only once.
These are the number of loop executions:
# threads before after
1000 1003002 3003
2000 4006002 6003
3000 9009002 9003
4000 16012002 12003
5000 25015002 15003
6000 36018002 18003
7000 49021002 21003
8000 64024002 24003
9000 81027002 27003
10000 100030002 30003
This last table shows pretty well the O(n^2) vs O(n) behaviors.
Reg-tested on x86 GNU/Linux (Ubuntu 16.04).
gdb/ChangeLog:
YYYY-MM-DD Laurent Morichetti <Laurent.Morichetti@amd.com>
YYYY-MM-DD Simon Marchi <simon.marchi@efficios.com>
* infrun.c (stop_all_threads): Collect multiple wait events at
each pass.
Remove TYPE_CODE, changing all the call sites to use type::code
directly. This is quite a big diff, but this was mostly done using sed
and coccinelle. A few call sites were done by hand.
gdb/ChangeLog:
* gdbtypes.h (TYPE_CODE): Remove. Change all call sites to use
type::code instead.
Add the code and set_code methods on code, in order to remove the
TYPE_CODE macro. In this patch, the TYPE_CODE macro is changed to use
type::code, so all the call sites that are used to set the type code are
changed to use type::set_code. The next patch will remove TYPE_CODE
completely.
gdb/ChangeLog:
* gdbtypes.h (struct type) <code, set_code>: New methods.
(TYPE_CODE): Use type::code. Change all call sites used to set
the code to use type::set_code instead.
In stop_all_threads, GDB sends signals to other threads in an attempt
to stop them. While in a typical scenario the expected wait status is
TARGET_WAITKIND_STOPPED, it is possible that the thread GDB attempted
to stop has already terminated. If so, a waitstatus other than
TARGET_WAITKIND_STOPPED would be received. Handle this case
appropriately.
If a wait status that denotes thread termination is ignored, GDB goes
into an infinite loop in stop_all_threads.
E.g.:
$ gdb ./a.out
(gdb) start
...
(gdb) add-inferior -exec ./a.out
...
(gdb) inferior 2
...
(gdb) start
...
(gdb) set schedule-multiple on
(gdb) set debug infrun 2
(gdb) continue
Continuing.
infrun: clear_proceed_status_thread (process 10449)
infrun: clear_proceed_status_thread (process 10453)
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: proceed: resuming process 10449
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 10449] at 0x55555555514e
infrun: infrun_async(1)
infrun: prepare_to_wait
infrun: proceed: resuming process 10453
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 10453] at 0x55555555514e
infrun: prepare_to_wait
infrun: Found 2 inferiors, starting at #0
infrun: target_wait (-1.0.0, status) =
infrun: 10449.10449.0 [process 10449],
infrun: status->kind = exited, status = 0
infrun: handle_inferior_event status->kind = exited, status = 0
[Inferior 1 (process 10449) exited normally]
infrun: stop_waiting
infrun: stop_all_threads
infrun: stop_all_threads, pass=0, iterations=0
infrun: process 10453 executing, need stop
infrun: target_wait (-1.0.0, status) =
infrun: 10453.10453.0 [process 10453],
infrun: status->kind = exited, status = 0
infrun: stop_all_threads status->kind = exited, status = 0 process 10453
infrun: process 10453 executing, already stopping
infrun: target_wait (-1.0.0, status) =
infrun: -1.0.0 [process -1],
infrun: status->kind = no-resumed
infrun: infrun_async(0)
infrun: stop_all_threads status->kind = no-resumed process -1
infrun: process 10453 executing, already stopping
infrun: stop_all_threads status->kind = no-resumed process -1
infrun: process 10453 executing, already stopping
infrun: stop_all_threads status->kind = no-resumed process -1
infrun: process 10453 executing, already stopping
infrun: stop_all_threads status->kind = no-resumed process -1
infrun: process 10453 executing, already stopping
infrun: stop_all_threads status->kind = no-resumed process -1
infrun: process 10453 executing, already stopping
infrun: stop_all_threads status->kind = no-resumed process -1
infrun: process 10453 executing, already stopping
infrun: stop_all_threads status->kind = no-resumed process -1
infrun: process 10453 executing, already stopping
infrun: stop_all_threads status->kind = no-resumed process -1
infrun: process 10453 executing, already stopping
infrun: stop_all_threads status->kind = no-resumed process -1
infrun: process 10453 executing, already stopping
infrun: stop_all_threads status->kind = no-resumed process -1
infrun: process 10453 executing, already stopping
...
And this polling goes on forever. This patch prevents the infinite
looping behavior. For the same scenario above, we obtain the
following behavior:
...
(gdb) continue
Continuing.
infrun: clear_proceed_status_thread (process 31229)
infrun: clear_proceed_status_thread (process 31233)
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: proceed: resuming process 31229
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 31229] at 0x55555555514e
infrun: infrun_async(1)
infrun: prepare_to_wait
infrun: proceed: resuming process 31233
infrun: resume (step=0, signal=GDB_SIGNAL_0), trap_expected=0, current thread [process 31233] at 0x55555555514e
infrun: prepare_to_wait
infrun: Found 2 inferiors, starting at #0
infrun: target_wait (-1.0.0, status) =
infrun: 31229.31229.0 [process 31229],
infrun: status->kind = exited, status = 0
infrun: handle_inferior_event status->kind = exited, status = 0
[Inferior 1 (process 31229) exited normally]
infrun: stop_waiting
infrun: stop_all_threads
infrun: stop_all_threads, pass=0, iterations=0
infrun: process 31233 executing, need stop
infrun: target_wait (-1.0.0, status) =
infrun: 31233.31233.0 [process 31233],
infrun: status->kind = exited, status = 0
infrun: stop_all_threads status->kind = exited, status = 0 process 31233
infrun: saving status status->kind = exited, status = 0 for 31233.31233.0
infrun: process 31233 not executing
infrun: stop_all_threads, pass=1, iterations=1
infrun: process 31233 not executing
infrun: stop_all_threads done
(gdb)
The exit event from Inferior 1 is received and shown to the user.
The exit event from Inferior 2 is not displayed, but kept pending.
(gdb) info inferiors
Num Description Connection Executable
* 1 <null> a.out
2 process 31233 1 (native) a.out
(gdb) inferior 2
[Switching to inferior 2 [process 31233] (a.out)]
[Switching to thread 2.1 (process 31233)]
Couldn't get registers: No such process.
(gdb) continue
Continuing.
infrun: clear_proceed_status_thread (process 31233)
infrun: clear_proceed_status_thread: thread process 31233 has pending wait status status->kind = exited, status = 0 (currently_stepping=0).
infrun: proceed (addr=0xffffffffffffffff, signal=GDB_SIGNAL_DEFAULT)
infrun: proceed: resuming process 31233
infrun: resume: thread process 31233 has pending wait status status->kind = exited, status = 0 (currently_stepping=0).
infrun: prepare_to_wait
infrun: Using pending wait status status->kind = exited, status = 0 for process 31233.
infrun: target_wait (-1.0.0, status) =
infrun: 31233.31233.0 [process 31233],
infrun: status->kind = exited, status = 0
infrun: handle_inferior_event status->kind = exited, status = 0
[Inferior 2 (process 31233) exited normally]
infrun: stop_waiting
(gdb) info inferiors
Num Description Connection Executable
1 <null> a.out
* 2 <null> a.out
(gdb)
When a process exits and we leave the process exit event pending, we
need to make sure that at least one thread is left listed in the
inferior's thread list. This is necessary in order to make sure we
have a thread that we can later resume, so the process exit event can
be collected/reported.
When native debugging, the GNU/Linux back end already makes sure that
the last LWP isn't deleted.
When remote debugging against GNU/Linux GDBserver, the GNU/Linux
GDBserver backend also makes sure that the last thread isn't deleted
until the process exit event is reported to GDBserver core.
However, between the backend reporting the process exit event to
GDBserver core, and GDB consuming the event, GDB may update the thread
list and find no thread left in the process. The process exit event
will be pending somewhere in GDBserver's stop reply queue, or
gdb/remote.c's queue, or whathever other event queue inbetween
GDBserver and infrun.c's handle_inferior_event.
This patch tweaks remote.c's target_update_thread_list implementation
to avoid deleting the last thread of an inferior.
In the past, this case of inferior-with-no-threads led to a special
case at the bottom of handle_no_resumed, where it reads:
/* Note however that we may find no resumed thread because the whole
process exited meanwhile (thus updating the thread list results
in an empty thread list). In this case we know we'll be getting
a process exit event shortly. */
for (inferior *inf : all_non_exited_inferiors (ecs->target))
In current master, that code path is still reachable with the
gdb.threads/continue-pending-after-query.exp testcase, when tested
against GDBserver, with "maint set target-non-stop" forced "on".
With this patch, the scenario that loop was concerned about is still
properly handled, because the loop above it finds the process's last
thread with "executing" set to true, and thus the handle_no_resumed
function still returns true.
Since GNU/Linux native and remote are the only targets that support
non-stop mode, and with this patch, we always make sure the inferior
has at least one thread, this patch also removes that "inferior with
no threads" special case handling from handle_no_resumed.
Since remote.c now has a special case where we treat a thread that has
already exited as if it was still alive, we might need to tweak
remote.c's target_thread_alive implementation to return true for that
thread without querying the remote side (which would say "no, not
alive"). After inspecting all the target_thread_alive calls in the
codebase, it seems that only the one from prune_threads could result
in that thread being accidentally deleted. There's only one call to
prune_threads in GDB's common code, so this patch handles this by
replacing the prune_threads call with a delete_exited_threads call.
This seems like an improvement anyway, because we'll still be doing
what the comment suggests we want to do, and, we avoid remote protocol
traffic.
Regression-tested on X86_64 Linux.
gdb/ChangeLog:
2020-05-14 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
Tom de Vries <tdevries@suse.de>
Pedro Alves <palves@redhat.com>
PR threads/25478
* infrun.c (stop_all_threads): Do NOT ignore
TARGET_WAITKIND_NO_RESUMED, TARGET_WAITKIND_THREAD_EXITED,
TARGET_WAITKIND_EXITED, TARGET_WAITKIND_SIGNALLED wait statuses
received.
(handle_no_resumed): Remove code handling a live inferior with no
threads.
* remote.c (has_single_non_exited_thread): New.
(remote_target::update_thread_list): Do not delete a thread if is
the last thread of the process.
* thread.c (thread_select): Call delete_exited_threads instead of
prune_threads.
gdb/testsuite/ChangeLog:
2020-05-14 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
Pedro Alves <palves@redhat.com>
* gdb.multi/multi-exit.c: New file.
* gdb.multi/multi-exit.exp: New file.
* gdb.multi/multi-kill.c: New file.
* gdb.multi/multi-kill.exp: New file.
In stop_all_threads, the thread events of the current top target are
enabled at the beginning of the function and then disabled at the end
(at scope exit time). Because there may be multiple targets whose
thread lists will be updated and whose threads are stopped,
enable/disable thread events for all targets.
This update caused a change in the annotations. In particular, a
"frames-invalid" annotation is printed one more time due to switching
the current inferior. Hence, gdb.base/annota1.exp and
gdb.cp/annota2.exp tests are also updated.
Regression-tested on X86_64 Linux using the default board file and the
native-extended-gdbserver board file.
gdb/ChangeLog:
2020-05-14 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* infrun.c (stop_all_threads): Enable/disable thread events of all
targets. Move a debug message denoting the end of the function
into the SCOPED_EXIT block.
gdb/testsuite/ChangeLog:
2020-05-14 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* gdb.base/annota1.exp: Update the expected output.
* gdb.cp/annota2.exp: Ditto.
Introduce two new convenience functions:
1. all_non_exited_process_targets: returns a collection of all process
stratum targets that have non-exited inferiors on them. Useful for
iterating targets.
2. switch_to_target_no_thread: switch the context to the first
inferior of the given target, and to no selected thread.
gdb/ChangeLog:
2020-05-14 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* process-stratum-target.h: Include <set>.
(all_non_exited_process_targets, switch_to_target_no_thread): New
function declarations.
* process-stratum-target.c (all_non_exited_process_targets)
(switch_to_target_no_thread): New function implementations.
This is a refactoring. The extracted function is placed deliberately
before 'stop_all_threads' because the function will be re-used there
in a subsequent patch for handling an exit status kind received from
a thread that GDB attempted to stop.
gdb/ChangeLog:
2020-05-14 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* infrun.c (handle_inferior_event): Extract out a piece of code
into...
(mark_non_executing_threads): ...this new function.
Change-Id: I2b088f4a724f4260cb37068264964525cf62a118
In infrun.c's resume_1 function, move the definition of the local
variable PC down to its first use. This is useful if the thread we want
to resume is already gone with a pending exit event, because we avoid
the error we would see otherwise when trying to read the PC.
gdb/ChangeLog:
2020-05-14 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* infrun.c (resume_1): Move a 'regcache_read_pc' call down to first
use.
It possible that a thread whose PC we attempt to read is already dead.
In this case, 'regcache_read_pc' errors out. This impacts the
"proceed" execution flow, where GDB quits early before having a chance
to check if there exists a pending event. To remedy, keep going with
a 0 value for the PC if 'regcache_read_pc' fails. Because the value
of PC before resuming a thread is mostly used for storing and checking
the next time the thread stops, this tolerance is expected to be
harmless for a dead thread/process.
gdb/ChangeLog:
2020-05-14 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* regcache.c (regcache_read_pc_protected): New function
implementation that returns 0 if the PC cannot read via
'regcache_read_pc'.
* infrun.c (proceed): Call 'regcache_read_pc_protected'
instead of 'regcache_read_pc'.
(keep_going_pass_signal): Ditto.
gdbsupport/ChangeLog:
2020-05-14 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* common-regcache.h (regcache_read_pc_protected): New function
declaration.
I recently noticed the align_value function in ada-lang.c. This can
be removed, in favor of align_up from gdbsupport.
gdb/ChangeLog
2020-05-13 Tom Tromey <tromey@adacore.com>
* ada-lang.c (align_value): Remove.
(ada_template_to_fixed_record_type_1): Use align_up.
The async-event.[ch] files were introduced recently as a result of
splitting the event-loop. I believe the copyright year update was
just an oversight. So, this patch fixes that.
gdb/ChangeLog:
2020-05-13 Tankut Baris Aktemur <tankut.baris.aktemur@intel.com>
* async-event.c: Update the copyright year.
* async-event.h: Update the copyright year.
As discussed on gdb-patches, this restores info_command and the
breakpoint on info_command in gdb-gdb.gdb. This reverts a tiny part
of 0743fc83c0 ("Replace most calls to help_list and cmd_show_list"),
as well as 652fc23a30 ("Remove gdb-gdb.gdb breakpoint on disappeared
function info_command.").
gdb/ChangeLog
2020-05-11 Tom Tromey <tromey@adacore.com>
* cli/cli-cmds.c (info_command): Restore.
(_initialize_cli_cmds): Use add_prefix_command for "info".
* gdb-gdb.gdb.in: Restore breakpoint on info_command.
The val_print removal patches introduced an Ada regression on PPC64
(probably any big-endian system).
The issue comes because value_field does not understand that Ada
wrapper fields can be bitfields that wrap a non-scalar type. In this
case the value is already left-justified, so the justification done
there does the wrong thing.
Perhaps it would be good, eventually, to change value_field to
understand this case. In the meantime this implements an Ada-specific
solution.
gdb/ChangeLog
2020-05-11 Tom Tromey <tromey@adacore.com>
* ada-lang.c (ada_value_primitive_field): Now public.
* ada-lang.h (ada_value_primitive_field): Declare.
* ada-valprint.c (print_field_values): Use
ada_value_primitive_field for wrapper fields.
When running test-case gdb.fortran/info-modules.exp with target board
debug-names, I run into:
...
FAIL: gdb.fortran/info-modules.exp: info modules: check for entry \
'info-types-2.f90', '18', 'mod2'
...
In more detail, comparing the behaviour of the executable without and with
.debug_names section, we have:
...
-$ gdb -batch info-modules -ex "info modules"
+$ gdb -batch info-modules.debugnames -ex "info modules"
All defined modules:
-File /data/gdb_versions/devel/src/gdb/testsuite/gdb.fortran/info-types-2.f90:
-18: mod2
-
File /data/gdb_versions/devel/src/gdb/testsuite/gdb.fortran/info-types.f90:
16: mod1
...
This is due to the fact that the .debug_names section does not contain
DW_TAG_module entries.
Fix this in debug_names::psymbol_tag.
Build and tested on x86_64-linux with target board debug-names.
gdb/ChangeLog:
2020-05-11 Tom de Vries <tdevries@suse.de>
* dwarf2/index-write.c (debug_names::psymbol_tag): Handle
MODULE_DOMAIN.
Consider the following two-file test-case:
...
$ cat main.c
extern int foo (void);
int
main (void)
{
int sum, a, b;
sum = a + b + foo ();
return sum;
}
$ cat foo.c
int
foo (void)
{
return 3;
}
...
Compiled like this:
...
$ clang-10 -gdwarf-5 -gpubnames -c main.c
$ clang-10 -gdwarf-5 -c foo.c
$ clang-10 -gdwarf-5 -gpubnames main.o foo.o
...
When loading this exec into gdb, we run into this assert:
...
$ gdb a.out
Reading symbols from a.out...
warning: Section .debug_aranges in a.out entry at offset 0 \
debug_info_offset 0 does not exists, ignoring .debug_aranges.
src/gdb/dwarf2/read.c:6949: \
internal-error: cutu_reader::cutu_reader(dwarf2_per_cu_data*, \
abbrev_table*, int, bool): \
Assertion `this_cu->length == cu->header.get_length ()' failed.
...
The problem is that the determined length of the CU:
...
(gdb) p /x this_cu->length
$4 = 0x26a
...
does not match the actual length:
...
(gdb) p /x cu->header.get_length ()
$5 = 0x59
...
The length of the CU is determined in create_cus_from_debug_names_list, and
set based on this list in the .debug_names section:
...
Compilation Unit offsets [
CU[0]: 0x000000c7
]
...
and it is assumed that this is a complete list, so the size of the CU is
calculated using the end of the .debug_section at 0x331, making it 0x331 -
0xc7 == 0x26a.
However, the CU list is not complete:
...
$ llvm-dwarfdump -debug-info a.out \
| grep "Compile Unit" \
| sed 's/Compile Unit.*//'
0x00000000:
0x0000002e:
0x000000a5:
0x000000c7:
0x00000120:
0x00000157:
0x0000030f:
...
In particular, because the CU for foo.c is there at 0x120 (the rest of the CUs
is due to openSUSE having debug info for various linked in objects).
Fix the assert by not assuming to know the length of CUs in
create_cus_from_debug_names_list (if the .debug_names is not produced by GDB),
and setting it to 0, and setting it later to the actual length.
Note that this does not fix the .debug_aranges warning, that's PR25969.
Build and tested on x86_64-linux, with native and debug-names.
gdb/ChangeLog:
2020-05-11 Tom de Vries <tdevries@suse.de>
PR symtab/25941
* dwarf2/read.c (create_cus_from_debug_names_list): Initialize CUs
with length 0, if not gdb-produced.
(cutu_reader::cutu_reader): Set CU length to actual length if 0.
gdb/testsuite/ChangeLog:
2020-05-11 Tom de Vries <tdevries@suse.de>
PR symtab/25941
* gdb.dwarf2/clang-debug-names.exp.in: New include exp file, factored
out of ...
* gdb.dwarf2/clang-debug-names.exp: ... here.
* gdb.dwarf2/clang-debug-names-2.exp: New file. Include
clang-debug-names.exp.in.
* gdb.dwarf2/clang-debug-names-2-foo.c: New test.
* gdb.dwarf2/clang-debug-names-2.c: New test.
When running test-case gdb.mi/mi-catch-cpp-exceptions.exp, we have:
...
FAIL: gdb.mi/mi-catch-cpp-exceptions.exp: all with invalid regexp: run until \
breakpoint in main (unknown output after running)
...
This is a regression since commit 596dc4adff "Speed up psymbol reading by
removing a copy".
Before that commit, we have:
...
$ gdb \
-batch \
./outputs/gdb.mi/mi-catch-cpp-exceptions/mi-catch-cpp-exceptions \
-ex "break 67" \
-ex "catch throw -r blahblah" \
-ex r
Breakpoint 1 at 0x4008e5: file mi-catch-cpp-exceptions.cc, line 67.
Catchpoint 2 (throw)
Breakpoint 1, main () at mi-catch-cpp-exceptions.cc:67
67 return 1; /* Stop here. */
...
In other words:
- we set a breakpoint somewhere in main,
- we set a catchpoint with a regexp that is intended to not match any
exception, and
- run to the breakpoint, without the catchpoint triggering.
After the commit, we have:
...
$ gdb \
-batch \
./outputs/gdb.mi/mi-catch-cpp-exceptions/mi-catch-cpp-exceptions \
-ex "break 67" \
-ex "catch throw -r blahblah" \
-ex r
Breakpoint 1 at 0x4008e5: file mi-catch-cpp-exceptions.cc, line 67.
Catchpoint 2 (throw)
Catchpoint 2 (exception thrown), 0x00007ffff7ab037e in __cxa_throw () from \
/usr/lib64/libstdc++.so.6
...
In other words, the catchpoint triggers.
This is caused by this bit of the commit:
...
type_name = cplus_typename_from_type_info (typeinfo_arg);
canon = cp_canonicalize_string (type_name.c_str ());
- if (!canon.empty ())
- std::swap (type_name, canon);
+ name = (canon == nullptr
+ ? canon.get ()
+ : type_name.c_str ());
}
catch (const gdb_exception_error &e)
{
exception_print (gdb_stderr, e);
}
- if (!type_name.empty ())
+ if (name != nullptr)
{
- if (self->pattern->exec (type_name.c_str (), 0, NULL, 0) != 0)
+ if (self->pattern->exec (name, 0, NULL, 0) != 0)
...
Before the commit, we have:
- type_name == "my_exception"
- canon = ""
and the !type_name.empty () test succeeds, and gdb executes the
self->pattern->exec call.
After the commit, we have:
- type_name == "my_exception"
- canon == NULL
- name == NULL
and the name != nullptr test fails, and gdb doesn't execute the
self->pattern->exec call.
Fix this by inverting the condition for the calculation of name:
...
- name = (canon == nullptr
+ name = (canon != nullptr
...
Build and tested on x86_64-linux.
gdb/ChangeLog:
2020-05-09 Tom de Vries <tdevries@suse.de>
PR gdb/25955
* break-catch-throw.c (check_status_exception_catchpoint): Fix name
calculation.
I noticed that "server_command" is an int, but really it should be a
bool.
gdb/ChangeLog
2020-05-09 Tom Tromey <tom@tromey.com>
* top.c (server_command): Now bool.
* top.h (server_command): Now bool.
A customer reported a crash in the DWARF reader.
Investigation showed that the crash occurred in an unusual scenario: a
function was lexically scoped within some other function -- but the
inner function inlined the outer function and referred to its DIE via
DW_AT_abstract_origin. With the executable in question,
inherit_abstract_dies could eventually call read_lexical_block_scope,
which in turn could recurse into process_die, to process a DIE that
was already being read, triggering an assert.
This came up once before; see:
https://www.sourceware.org/ml/gdb-patches/2014-02/msg00652.html
However, in this case, I don't have an easy way to reproduce. So,
there is no test case.
I did experiment with the failing executable. This patch fixes the
bug and doesn't seem to cause other issues. For example, I can still
set breakpoints on the relevant functions.
gdb/ChangeLog
2020-05-08 Tom Tromey <tromey@adacore.com>
* dwarf2/read.c (read_lexical_block_scope): Don't process a DIE
already being processed.
This changes displays to have a constructor, use bool and std::string,
and to be stored using std::vector. The ALL_DISPLAYS and
ALL_DISPLAYS_SAFE macros are removed. While internal iteration is
still done via map_display_numbers, this is updated to use a
function_view. These changes simplify the code somewhat; for example,
free_display can now be removed in favor of ordinary destruction.
gdb/ChangeLog
2020-05-08 Tom Tromey <tom@tromey.com>
* printcmd.c (struct display) <next>: Remove.
<display>: New constructor.
<exp_string>: Now a std::string.
<enabled_p>: Now a bool.
(display_number): Move definition earlier.
(displays): Rename from display_chain. Now a std::vector.
(ALL_DISPLAYS, ALL_DISPLAYS_SAFE): Remove.
(display_command): Update.
(do_one_display, disable_display)
(enable_disable_display_command, do_enable_disable_display):
Update.
(free_display): Remove.
(clear_displays): Rewrite.
(delete_display): Update.
(map_display_numbers): Use function_view. Remove "data"
parameter. Update.
(do_delete_display): Remove.
(undisplay_command): Update.
(do_one_display, do_displays, disable_display)
(info_display_command): Update.
(do_enable_disable_display): Remove.
(enable_disable_display_command)
(clear_dangling_display_expressions): Update.
This patch started as an attempt to replace ALL_SO_LIBS with an
ordinary C++ iterator. However, then I tripped over the so_list_head
define again, and decided to remove it as well.
gdb/ChangeLog
2020-05-08 Tom Tromey <tom@tromey.com>
* mi/mi-cmd-file.c (mi_cmd_file_list_shared_libraries): Update.
* solib-svr4.c (svr4_fetch_objfile_link_map): Update.
(enable_break): Update.
* solib-frv.c (frv_fdpic_find_global_pointer): Update.
(frv_fdpic_find_canonical_descriptor): Update.
(frv_fetch_objfile_link_map): Update.
* progspace.c (program_space::free_all_objfiles): Update.
(program_space::solibs): New method.
* progspace.h (struct program_space) <solibs>: New method.
* solist.h (master_so_list): Don't declare.
(ALL_SO_LIBS): Remove.
* solib.h (so_list_head): Remove.
(update_solib_list): Update comment.
* solib.c (master_so_list): Remove.
(solib_used, update_solib_list, solib_add)
(info_sharedlibrary_command, clear_solib)
(reload_shared_libraries_1, remove_user_added_objfile): Update.
This removes the ALL_EXTENSION_LANGUAGES and
ALL_ENABLED_EXTENSION_LANGUAGES macros, in favor of ordinary
iterators. For ALL_ENABLED_EXTENSION_LANGUAGES, I chose to simply
inline the check, as that seemed simpler than trying to make
filtered_iterator work for std::array. (As an aside, this sort of
thing will be easier once we can use the ranges library...)
gdb/ChangeLog
2020-05-08 Tom Tromey <tom@tromey.com>
* extension.c (extension_languages): Now a std::array.
(ALL_EXTENSION_LANGUAGES): Remove.
(get_ext_lang_defn, get_ext_lang_of_file)
(eval_ext_lang_from_control_command): Update.
(finish_ext_lang_initialization)
(auto_load_ext_lang_scripts_for_objfile)
(ext_lang_type_printers::ext_lang_type_printers)
(apply_ext_lang_type_printers)
(ext_lang_type_printers::~ext_lang_type_printers)
(apply_ext_lang_val_pretty_printer, apply_ext_lang_frame_filter)
(preserve_ext_lang_values, get_breakpoint_cond_ext_lang)
(breakpoint_ext_lang_cond_says_stop, check_quit_flag)
(get_matching_xmethod_workers, ext_lang_colorize)
(ext_lang_before_prompt): Update.
(ALL_ENABLED_EXTENSION_LANGUAGES): Remove.
I noticed that cp_canonicalize_string and friends copy a
unique_xmalloc_ptr to a std::string. However, this copy isn't
genuinely needed anywhere, and it serves to slow down DWARF psymbol
reading.
This patch removes the copy and updates the callers to adapt.
This speeds up the reader from 1.906 seconds (mean of 10 runs, of gdb
on a copy of itself) to 1.888 seconds (mean of 10 runs, on the same
copy as the first trial).
gdb/ChangeLog
2020-05-08 Tom Tromey <tom@tromey.com>
* symtab.h (class demangle_result_storage) <set_malloc_ptr>: New
overload.
<swap_string, m_string>: Remove.
* symtab.c (demangle_for_lookup, completion_list_add_symbol):
Update.
* stabsread.c (define_symbol, read_type): Update.
* linespec.c (find_linespec_symbols): Update.
* gnu-v3-abi.c (gnuv3_get_typeid): Update.
* dwarf2/read.c (dwarf2_canonicalize_name): Update.
* dbxread.c (read_dbx_symtab): Update.
* cp-support.h (cp_canonicalize_string_full)
(cp_canonicalize_string, cp_canonicalize_string_no_typedefs):
Return unique_xmalloc_ptr.
* cp-support.c (inspect_type): Update.
(cp_canonicalize_string_full): Return unique_xmalloc_ptr.
(cp_canonicalize_string_no_typedefs, cp_canonicalize_string):
Likewise.
* c-typeprint.c (print_name_maybe_canonical): Update.
* break-catch-throw.c (check_status_exception_catchpoint):
Update.
When running test-case gdb.threads/fork-child-threads.exp with gcc-8 instead
of gcc-7, we have:
...
(gdb) next^M
[Attaching after Thread 0x7ffff7fae740 (LWP 27574) fork to child process \
27578]^M
[New inferior 2 (process 27578)]^M
[Detaching after fork from parent process 27574]^M
[Inferior 1 (process 27574) detached]^M
[Thread debugging using libthread_db enabled]^M
Using host libthread_db library "/lib64/libthread_db.so.1".^M
[Switching to Thread 0x7ffff7fae740 (LWP 27578)]^M
-main () at src/gdb/testsuite/gdb.threads/fork-child-threads.c:41^M
+main () at src/gdb/testsuite/gdb.threads/fork-child-threads.c:34^M
-41 i = pthread_create (&thread, NULL, start, NULL);^M
+34 switch (fork ())^M
-(gdb) PASS: gdb.threads/fork-child-threads.exp: next over fork
+(gdb) FAIL: gdb.threads/fork-child-threads.exp: next over fork
...
This is due to the fact that gcc-8 generates more precise line info, making
the instruction after the call to fork a "recommended breakpoint location".
However, it is a bug because next is supposed to move to the next source
line.
The problem is that in process_event_stop_test we hit this code:
...
if ((ecs->event_thread->suspend.stop_pc == stop_pc_sal.pc)
&& (ecs->event_thread->current_line != stop_pc_sal.line
|| ecs->event_thread->current_symtab != stop_pc_sal.symtab))
{
if (stop_pc_sal.is_stmt)
{
/* We are at the start of a different line. So stop. Note that
we don't stop if we step into the middle of a different line.
That is said to make things like for (;;) statements work
better. */
if (debug_infrun)
fprintf_unfiltered (gdb_stdlog,
"infrun: stepped to a different line\n");
end_stepping_range (ecs);
return;
}
...
because current_line and current_symtab have initial values:
...
(gdb) p ecs->event_thread->current_line
$8 = 0
(gdb) p ecs->event_thread->current_symtab
$9 = (symtab *) 0x0
...
Fix this in follow_fork by copying current_line and current_symtab from
parent thread to child thread.
Tested on x86_64-linux, with gcc 7.5.0 and gcc 10.0.1.
gdb/ChangeLog:
2020-05-08 Tom de Vries <tdevries@suse.de>
* infrun.c (follow_fork): Copy current_line and current_symtab to
child thread.
This is a small cleanup to normalize the structures in async-event.c
with the rest of the code base:
- Remove the unnecessary typedefs
- Fix indentation of struct bodies
- Put comments above fields
No functional changes expected.
gdb/ChangeLog:
* async-event.c (struct async_signal_handler, struct
async_event_handler): Reformat, remove typedef.
Remove this macro, which abstracts how to obtain the dyn_prop_list of a
given type. We could replace it with a method on `struct type`, but I
don't think it's needed, as the only code that accesses the dynamic prop
list directly is internal gdbtypes.c code (that can be seen as code
internal to `struct type`). So it can just refer to the field directly.
gdb/ChangeLog:
* gdbtypes.h (TYPE_DYN_PROP_LIST): Remove. Update all users
access thistype->main_type->dyn_prop_list directly.
Move remove_dyn_prop, currently a free function, to be a method of
struct type.
gdb/ChangeLog:
* gdbtypes.h (struct type) <remove_dyn_prop>: New method.
(remove_dyn_prop): Remove. Update all users to use
type::remove_dyn_prop.
* gdbtypes.c (remove_dyn_prop): Rename to...
(type::remove_dyn_prop): ... this.
Move add_dyn_prop, currently a free function, to be a method of struct
type.
gdb/ChangeLog:
* gdbtypes.h (struct type) <add_dyn_prop>: New method.
(add_dyn_prop): Remove. Update all users to use
type::add_dyn_prop.
* gdbtypes.c (add_dyn_prop): Rename to...
(type::add_dyn_prop): ... this.
Move get_dyn_prop, currently a free function, to be a method on struct
type.
gdb/ChangeLog:
* gdbtypes.h (struct type) <get_dyn_prop>: New method.
(get_dyn_prop): Remove. Update all users to use
type::dyn_prop.
* gdbtypes.c (get_dyn_prop): Rename to...
(type::dyn_prop): ... this.
v2:
- test: build full executable instead of object
- test: add and use supports_fcf_protection
- test: use gdb_test_multiple's -wrap option
- test: don't execute gdb_assert if failed to get breakpoint address
Some GCCs now enable -fcf-protection by default. This is the case, for
example, with GCC 9.3.0 on Ubuntu 20.04. Enabling it causes the
`endbr64` instruction to be inserted at the beginning of all functions
and that breaks GDB's prologue analysis.
I noticed this because it gives many failures in gdb.base/break.exp.
But let's take this dummy program and put a breakpoint on main:
int main(void)
{
return 0;
}
Without -fcf-protection, the breakpoint is correctly put after the prologue:
$ gcc test.c -g3 -O0 -fcf-protection=none
$ ./gdb -q -nx --data-directory=data-directory a.out
Reading symbols from a.out...
(gdb) disassemble main
Dump of assembler code for function main:
0x0000000000001129 <+0>: push %rbp
0x000000000000112a <+1>: mov %rsp,%rbp
0x000000000000112d <+4>: mov $0x0,%eax
0x0000000000001132 <+9>: pop %rbp
0x0000000000001133 <+10>: retq
End of assembler dump.
(gdb) b main
Breakpoint 1 at 0x112d: file test.c, line 3.
With -fcf-protection, the breakpoint is incorrectly put on the first
byte of the function:
$ gcc test.c -g3 -O0 -fcf-protection=full
$ ./gdb -q -nx --data-directory=data-directory a.out
Reading symbols from a.out...
(gdb) disassemble main
Dump of assembler code for function main:
0x0000000000001129 <+0>: endbr64
0x000000000000112d <+4>: push %rbp
0x000000000000112e <+5>: mov %rsp,%rbp
0x0000000000001131 <+8>: mov $0x0,%eax
0x0000000000001136 <+13>: pop %rbp
0x0000000000001137 <+14>: retq
End of assembler dump.
(gdb) b main
Breakpoint 1 at 0x1129: file test.c, line 2.
Stepping in amd64_skip_prologue, we can see that the prologue analysis,
for GCC-compiled programs, is done in amd64_analyze_prologue by decoding
the instructions and looking for typical patterns. This patch changes
the analysis to check for a prologue starting with the `endbr64`
instruction, and skip it if it's there.
gdb/ChangeLog:
* amd64-tdep.c (amd64_analyze_prologue): Check for `endbr64`
instruction, skip it if it's there.
gdb/testsuite/ChangeLog:
* gdb.arch/amd64-prologue-skip-cf-protection.exp: New file.
* gdb.arch/amd64-prologue-skip-cf-protection.c: New file.
It is unused. The corresponding macro was removed in c3236f84c1 ("gdb:
remove TYPE_INCOMPLETE").
gdb/ChangeLog:
* gdbtypes.h (struct main_type) <flag_incomplete>: Remove.
The "HP platforms" comment prompted me to check if this was still used
somewhere. Apparently it's not, so remove it.
gdb/ChangeLog:
* gdbtypes.h (TYPE_INCOMPLETE): Remove.
* gdbtypes.c (recursive_dump_type): Remove use of
TYPE_INCOMPLETE.
I looked at all the calls to add_prefix_cmd, and replaced them with
calls to add_basic_prefix_cmd or add_show_prefix_cmd when appropriate.
This makes gdb's command language a bit more regular. I don't think
there's a significant downside.
Note that this patch removes a couple of tests. The removed ones are
completely redundant.
gdb/ChangeLog
2020-05-03 Tom Tromey <tom@tromey.com>
* breakpoint.c (catch_command, tcatch_command): Remove.
(_initialize_breakpoint): Use add_basic_prefix_cmd,
add_show_prefix_cmd.
(set_breakpoint_cmd, show_breakpoint_cmd): Remove
* utils.c (set_internal_problem_cmd, show_internal_problem_cmd):
Remove.
(add_internal_problem_command): Use add_basic_prefix_cmd,
add_show_prefix_cmd.
* mips-tdep.c (set_mipsfpu_command): Remove.
(_initialize_mips_tdep): Use add_basic_prefix_cmd.
* dwarf2/index-cache.c (set_index_cache_command): Remove.
(_initialize_index_cache): Use add_basic_prefix_cmd.
* memattr.c (dummy_cmd): Remove.
(_initialize_mem): Use add_basic_prefix_cmd, add_show_prefix_cmd.
* tui/tui-win.c (set_tui_cmd, show_tui_cmd): Remove.
(_initialize_tui_win): Use add_basic_prefix_cmd,
add_show_prefix_cmd.
* cli/cli-logging.c (set_logging_command): Remove.
(_initialize_cli_logging): Use add_basic_prefix_cmd,
add_show_prefix_cmd.
(show_logging_command): Remove.
* target.c (target_command): Remove.
(add_target): Use add_basic_prefix_cmd.
gdb/testsuite/ChangeLog
2020-05-03 Tom Tromey <tom@tromey.com>
* gdb.base/sepdebug.exp: Remove "catch" test.
* gdb.base/break.exp: Remove "catch" test.
* gdb.base/default.exp: Update expected output.
The function info_command has disappeared, so this breakpoint does not
work anymore.
"info_command" was a function for the prefix command "info",
giving the list of "info" subcommands.
It is not very clear what the removed breakpoint and its associated
command list was supposed to do.
Removed and pushed as obvious, after discussion with Tom.
Report LWP CREATE and LWP EXIT events and setup this on post_attach()
and post_startup_inferior().
Stop reinitializing the list of recognized threads in update_thread_list().
Handle LWP CREATE and EXIT events in nbsd_nat_target::wait().
gdb/ChangeLog:
* nbsd-nat.c (nbsd_enable_proc_events)
(nbsd_nat_target::post_startup_inferior): Add.
(nbsd_nat_target::post_attach): Call `nbsd_enable_proc_events'.
(nbsd_nat_target::update_thread_list): Rewrite.
(nbsd_nat_target::wait): Handle "PTRACE_LWP_EXIT" and
"PTRACE_LWP_CREATE".
* nbsd-nat.h (nbsd_nat_target::post_startup_inferior): Add.
This reverts commit 84ed7a4725.
The problem that the commit attempts to address has already been fixed in
commit 770479f223 "gdb: Fix toplevel types with -fdebug-types-section".
The commit itself is superfluous because it sets list_in_scope at a point that
it's already set (by start_symtab).
"frame" and "f" are created twice by stack.c _initialize_stack.
Remove the second creation.
Regression tested on amd64/Debian.
2020-04-30 Philippe Waroquiers <philippe.waroquiers@skynet.be>
* stack.c (_initialize_stack): Remove duplicated creation
of "frame" command and "f" alias.
Sizes of stubbed types are calculated on demand in check_typedef, so the
same must also be done for arrays of stubbed types.
A stubbed type is usually a structure that has only been forward declared,
but can also happen if the structure has a virtual function that's not
inline in the class definition.
For these stubbed types, the size must be recalculated once the full
definition is available.
gdb/ChangeLog:
2020-04-30 Hannes Domani <ssbssa@yahoo.de>
PR gdb/18706
* gdbtypes.c (check_typedef): Calculate size of array of
stubbed type.
gdb/testsuite/ChangeLog:
2020-04-30 Hannes Domani <ssbssa@yahoo.de>
PR gdb/18706
* gdb.cp/stub-array-size.cc: New test.
* gdb.cp/stub-array-size.exp: New file.
* gdb.cp/stub-array-size.h: New test.
* gdb.cp/stub-array-size2.cc: New test.
Non-static member functions for Windows 32bit programs need the thiscall
calling convention, so the 'this' pointer needs to be passed in ECX.
gdb/ChangeLog:
2020-04-30 Hannes Domani <ssbssa@yahoo.de>
PR gdb/15559
* i386-tdep.c (i386_push_dummy_call): Call
i386_thiscall_push_dummy_call.
(i386_thiscall_push_dummy_call): New function.
* i386-tdep.h (i386_thiscall_push_dummy_call): Declare.
* i386-windows-tdep.c (i386_windows_push_dummy_call): New function.
(i386_windows_init_abi): Call set_gdbarch_push_dummy_call.
shellcheck reports:
In gdbarch.sh line 53:
while IFS='' read line
^--^ SC2162: read without -r will mangle backslashes.
See the rationale at [1]. In our case, we actually want the backslashes
to be interpreted and removed. Silence the warning using a directive.
[1] https://github.com/koalaman/shellcheck/wiki/SC2162
gdb/ChangeLog:
* gdbarch.sh (do_read): Add shellcheck disable directive for
warning SC2162.
Fix all instances of this kind of warning:
In gdbarch.sh line 96:
m ) staticdefault="${predefault}" ;;
^-----------^ SC2154: predefault is referenced but not assigned.
These warnings appear because we are doing something a bit funky when reading
the gdbarch fields. These variables are not assigned explicitly, but
using some `eval` commands.
I don't think there is so much we can fix about those warnings. To
silence them, I've changed `${foo}` to `${foo:-}`. This tells the shell
to substitute with an empty string if `foo` is not defined. This
retains the current behavior, but the warnings go away.
gdb/ChangeLog:
* gdbarch.sh: Use ${foo:-} where shellcheck would report a
"referenced but not assigned" warning.
shellcheck reports:
In gdbarch.sh line 139:
fallbackdefault="0"
^-------------^ SC2034: fallbackdefault appears unused. Verify use (or export if used externally).
Indeed, the `fallbackdefault` variable appears to be unused, remove the
code that sets it.
gdb/ChangeLog:
* gdbarch.sh: Remove code that sets fallbackdefault.
Fix all warnings of this type:
In gdbarch.sh line 1238:
if [ "x${invalid_p}" = "x0" -a -n "${postdefault}" ]
^-- SC2166: Prefer [ p ] && [ q ] as [ p -a q ] is not well defined.
See the rationale here [1].
[1] https://github.com/koalaman/shellcheck/wiki/SC2166
gdb/ChangeLog:
* gdbarch.sh: Use shell operators && and || instead of
-a and -o.
Fix all instances of:
In gdbarch.sh line 2195:
printf " `echo "$function" | sed -e 's/./ /g'` %s %s)\n" "$returntype" "$function"
^-- SC2006: Use $(...) notation instead of legacy backticked `...`.
Did you mean:
printf " $(echo "$function" | sed -e 's/./ /g') %s %s)\n" "$returntype" "$function"
See here [1] for the rationale.
[1] https://github.com/koalaman/shellcheck/wiki/SC2006
gdb/ChangeLog:
* gdbarch.sh: Use $(...) instead of `...`.
Fix all instances of:
In gdbarch.sh line 31:
if test ! -r ${file}
^-----^ SC2086: Double quote to prevent globbing and word splitting.
Did you mean:
if test ! -r "${file}"
Note that some instances of these are in text that is eval'ed. I'm
pretty sure that things could go wrong during the eval too, but that's
not something shellcheck can check.
gdb/ChangeLog:
* gdbarch.sh: Use double quotes around variables.
Fix all instances of this:
In gdbarch.sh line 2182:
printf " gdb_assert (!(${invalid_p}));\n"
^-- SC2059: Don't use variables in the printf format string. Use printf "..%s.." "$foo".
... by doing exactly as the message suggests.
The rationale explained here [1] makes sense, if there happens to be a
format specifier in text substituted for the variable, the printf won't
do what we expect.
[1] https://github.com/koalaman/shellcheck/wiki/SC2059
gdb/ChangeLog:
* gdbarch.sh: Use %s with printf, instead of variables in the
format string.
PR ada/25875 concerns a gdb crash when gdb.ada/arr_enum_idx_w_gap.exp
is run using the .debug_types board.
The problem turns out to be caused by weird compiler output. In this
test, the compiler emits a top-level type that refers to an
enumeration type which is nested in a function. However, this
function is just a declaration.
This results in gdb calling read_enumeration_type for the enum type,
but process_enumeration_scope is never called, yielding an enum with
no fields. This causes the crash.
This patch fixes the problem by arranging to create the enum fields in
read_enumeration_type.
Tested on x86-64 Fedora 30.
gdb/ChangeLog
2020-04-29 Tom Tromey <tromey@adacore.com>
PR ada/25875:
* dwarf2/read.c (update_enumeration_type_from_children): Compute
type fields here.
(read_enumeration_type): Call
update_enumeration_type_from_children later. Update comments.
(process_enumeration_scope): Don't create type fields.
The syscall literal names are not stable on NetBSD and can change
once a syscall is versioned. Thus these names are internal to the
system and in GDB mostly descriptive, not intended to be a stable
interface with fixed names across GDB and NetBSD versions to track
certain syscalls.
gdb/ChangeLog:
* nbsd-tdep.c: Include "xml-syscall.h".
(nbsd_init_abi): Call `set_xml_syscall_file_name'.
Implement the following events:
- single step (TRAP_TRACE)
- software breakpoint (TRAP_DBREG)
- exec() (TRAP_EXEC)
- syscall entry/exit (TRAP_SCE / TRAP_SCX)
Add support for NetBSD specific ::wait () and ::resume ().
Instruct the generic code that exec and syscall events are supported.
Define an empty nbsd_get_syscall_number as it is prerequisite for
catching syscall entry and exit events, even if it is unused.
This function is used to detect whether the gdbarch supports the
'catch syscall' feature.
gdb/ChangeLog:
* nbsd-nat.c: Include "sys/wait.h".
(nbsd_resume, nbsd_nat_target::resume, nbsd_wait)
(nbsd_nat_target::wait, nbsd_nat_target::insert_exec_catchpoint)
(nbsd_nat_target::remove_exec_catchpoint)
(nbsd_nat_target::set_syscall_catchpoint): Add.
* nbsd-nat.h (nbsd_nat_target::resume, nbsd_nat_target::wait)
(nbsd_nat_target::insert_exec_catchpoint)
(nbsd_nat_target::remove_exec_catchpoint)
(nbsd_nat_target::set_syscall_catchpoint): Add.
* nbsd-tdep.c (nbsd_get_syscall_number): Add.
(nbsd_init_abi): Call `set_gdbarch_get_syscall_number' and pass
`nbsd_get_syscall_number'.
print_block_frame_labels has been commented out since 2010.
I don't think we need it; this patch removes it.
2020-04-29 Tom Tromey <tom@tromey.com>
* stack.c (print_block_frame_labels): Remove.
Currently, printing with array pretty formatting makes the output actually
less readable than without:
(gdb) p -array on -- {{1,2,3},{4,5,6}}
$1 = { {1,
2,
3},
{4,
5,
6}}
(gdb) p -array on -array-indexes on -- {{1,2,3},{4,5,6}}
$2 = {[0] = {[0] = 1,
[1] = 2,
[2] = 3},
[1] = {[0] = 4,
[1] = 5,
[2] = 6}}
These changes now also put the first element and the array end bracket on a new
line, similar to the structure pretty formatter:
(gdb) p -array on -- {{1,2,3},{4,5,6}}
$1 = {
{
1,
2,
3
},
{
4,
5,
6
}
}
(gdb) p -array on -array-indexes on -- {{1,2,3},{4,5,6}}
$2 = {
[0] = {
[0] = 1,
[1] = 2,
[2] = 3
},
[1] = {
[0] = 4,
[1] = 5,
[2] = 6
}
}
gdb/ChangeLog:
2020-04-29 Hannes Domani <ssbssa@yahoo.de>
PR gdb/17320
* ada-valprint.c (val_print_packed_array_elements): Move array
end bracket to new line.
(ada_val_print_string): Remove extra spaces before first array
element.
* c-valprint.c (c_value_print_array): Likewise.
* m2-valprint.c (m2_print_array_contents): Likewise.
(m2_value_print_inner): Likewise.
* p-valprint.c (pascal_value_print_inner): Likewise.
* valprint.c (generic_val_print_array): Likewise.
(value_print_array_elements): Move first array element and array
end bracket to new line.
gdb/testsuite/ChangeLog:
2020-04-29 Hannes Domani <ssbssa@yahoo.de>
PR gdb/17320
* gdb.base/pretty-array.c: New test.
* gdb.base/pretty-array.exp: New file.
With target board debug-types, we have:
...
FAIL: gdb.cp/cpexprs.exp: list policy1::function
...
This is a regression triggered by commit 770479f223 "gdb: Fix toplevel types
with -fdebug-types-section".
However, the FAIL is caused by commit 4dedf84da9 "Change
decode_compound_collector to use std::vector" which changes a VEC_iterate loop
into a range loop:
...
- for (ix = 0; VEC_iterate (symbolp, sym_classes, ix, sym); ++ix)
+ unsigned int ix = 0;
+ for (const auto &sym : *sym_classes)
...
but fails to ensure that the increment of ix happens every iteration.
Fix this by calculating the index variable at the start of the loop body:
...
for (const auto &elt : *sym_classes)
{
unsigned int ix = &elt - &*sym_classes->begin ();
...
Tested on x86_64-linux, with native and target board debug-types.
gdb/ChangeLog:
2020-04-29 Tom de Vries <tdevries@suse.de>
PR symtab/25889
* linespec.c (find_method): Fix ix calculation.
gdb/testsuite/ChangeLog:
2020-04-29 Tom de Vries <tdevries@suse.de>
PR symtab/25889
* gdb.cp/cpexprs.exp: Adapt for inclusion.
* gdb.cp/cpexprs-debug-types.exp: New file. Set -fdebug-types-section
and include cpexprs.exp.
All platforms on NetBSD use a shared system call table, so use a
single XML file to describe the system calls available on each NetBSD
platform.
gdb/ChangeLog:
* syscalls/update-netbsd.sh: New file.
* syscalls/netbsd.xml: Regenerate.
* data-directory/Makefile.in: Register `netbsd.xml' in
`SYSCALLS_FILES'
shellcheck reports:
In update-freebsd.sh line 72:
}' $1 >> freebsd.xml.tmp
^-- SC2086: Double quote to prevent globbing and word splitting.
Did you mean:
}' "$1" >> freebsd.xml.tmp
For more information:
https://www.shellcheck.net/wiki/SC2086 -- Double quote to prevent globbing ...
Add double quotes to fix it.
gdb/ChangeLog:
* syscalls/update-freebsd.sh: Add double quotes.
Now that Python code can create TUI windows, it seemed appropriate to
allow Python commands to appear in the "TUI" help class. This patch
adds this capability.
gdb/ChangeLog
2020-04-28 Tom Tromey <tom@tromey.com>
* NEWS: Update.
* python/py-cmd.c (gdbpy_initialize_commands): Add COMMAND_TUI.
(cmdpy_init): Allow class_tui.
gdb/doc/ChangeLog
2020-04-28 Tom Tromey <tom@tromey.com>
* python.texi (Commands In Python): Document gdb.COMMAND_TUI.
When building with g++ 4.8, we get this error (just an excerpt, because
g++ outputs a very long error message):
CXX dwarf2/read.o
...
/home/smarchi/src/binutils-gdb/gdb/dwarf2/read.c:14616:31: required from here
/usr/include/c++/4.8/bits/hashtable_policy.h:1070:12: error: invalid use of incomplete type ‘struct std::hash<sect_offset>’
struct _Hash_code_base<_Key, _Value, _ExtractKey, _H1, _H2,
This is the same problem and fix as in commit f23f598e28 ("[gdb] Fix
build breaker with gcc 4.8"). Pass an explicit hash function rather
than relying on the default std::hash<sect_offset>.
gdb/ChangeLog:
PR gdb/25881
* dwarf2/read.c (offset_map_type): Use
gdb:hash_enum<sect_offset> as hash function.
Consider a test-case with sources 36.c:
...
struct s { int i; };
extern void f (void);
int main (void) {
struct s a;
f ();
return 0;
}
...
and 36b.c:
...
struct s { int j; };
void f (void) {
struct s b;
}
...
compiled like this:
...
$ gcc 36.c 36b.c -g
...
It contains DWARF like this:
...
<0><d2>: Abbrev Number: 1 (DW_TAG_compile_unit)
<d8> DW_AT_name : 36.c
<1><f4>: Abbrev Number: 2 (DW_TAG_structure_type)
<f5> DW_AT_name : s
<2><fe>: Abbrev Number: 3 (DW_TAG_member)
<ff> DW_AT_name : i
<1><110>: Abbrev Number: 5 (DW_TAG_subprogram)
<111> DW_AT_name : main
<2><12d>: Abbrev Number: 6 (DW_TAG_variable)
<12e> DW_AT_name : a
<132> DW_AT_type : <0xf4>
<0><146>: Abbrev Number: 1 (DW_TAG_compile_unit)
<14c> DW_AT_name : 36b.c
<1><168>: Abbrev Number: 2 (DW_TAG_structure_type)
<169> DW_AT_name : s
<2><172>: Abbrev Number: 3 (DW_TAG_member)
<173> DW_AT_name : j
<1><184>: Abbrev Number: 5 (DW_TAG_subprogram)
<185> DW_AT_name : f
<2><19b>: Abbrev Number: 6 (DW_TAG_variable)
<19c> DW_AT_name : b
<1a0> DW_AT_type : <0x168>
...
And when printing "struct s", we get first a random one (with int j), and then
context-specific ones (with int i in main, and int j in f):
...
$ gdb -batch a.out \
-ex "ptype struct s" \
-ex start \
-ex "ptype struct s" \
-ex "break f" -ex continue \
-ex "ptype struct s" \
| grep "int [ij];"
int j;
int i;
int j;
...
Same for -readnow.
However, if we use -fdebug-types-section:
...
$ gcc 36.c 36b.c -g -fdebug-types-section
...
we get:
...
$ gdb ... | grep "int [ij];"
int j;
int i;
int i;
$ gdb -readnow ... | grep "int [ij];"
int j;
int j;
int j;
...
This is due to the fact that both "struct s" DIEs have been moved to the
.debug_types section:
...
Compilation Unit @ offset 0x0:
Signature: 0xfd1462823bb6f7b7
<0><17>: Abbrev Number: 1 (DW_TAG_type_unit)
<1><1d>: Abbrev Number: 2 (DW_TAG_structure_type)
<1e> DW_AT_name : s
<2><27>: Abbrev Number: 3 (DW_TAG_member)
<28> DW_AT_name : i
Compilation Unit @ offset 0x3a:
Signature: 0x534310fbefba324d
<0><51>: Abbrev Number: 1 (DW_TAG_type_unit)
<1><57>: Abbrev Number: 2 (DW_TAG_structure_type)
<58> DW_AT_name : s
<2><61>: Abbrev Number: 3 (DW_TAG_member)
<62> DW_AT_name : j
...
and there's no longer a "struct s" DIE in the 36.c and
and 36b.c CUs to specify which "struct s" belongs in the CU. This is gcc
PR90232.
However, using a tentative patch for gcc that adds these DIEs (according to
DWARF standard: If the complete declaration of a type has been placed in a
separate type unit, an incomplete declaration of that type in the compilation
unit may provide the unique 64-bit signature of the type using a
DW_AT_signature attribute):
...
<0><d2>: Abbrev Number: 5 (DW_TAG_compile_unit)
<d8> DW_AT_name : 36.c
+ <1><f4>: Abbrev Number: 6 (DW_TAG_structure_type)
+ <f5> DW_AT_name : s
+ <f7> DW_AT_signature : signature: 0xfd1462823bb6f7b7
+ <ff> DW_AT_declaration : 1
<0><13c>: Abbrev Number: 5 (DW_TAG_compile_unit)
<142> DW_AT_name : 36b.c
+ <1><15e>: Abbrev Number: 6 (DW_TAG_structure_type)
+ <15f> DW_AT_name : s
+ <161> DW_AT_signature : signature: 0x534310fbefba324d
+ <169> DW_AT_declaration : 1
...
still does not help, because they're declarations, so new_symbol is not called
for them in process_structure_scope.
Fix this by calling new_symbol for these decls.
Build and tested on x86_64-linux.
Also tested with target board enabling by default -fdebug-types-section
-gdwarf-4, and with gcc with aforementioned tentative patch. In this
configuration, the patch reduces number of FAILs from 2888 to 238.
gdb/ChangeLog:
2020-04-28 Tom de Vries <tdevries@suse.de>
* dwarf2/read.c (process_structure_scope): Add symbol for struct decl
with DW_AT_signature.
gdb/testsuite/ChangeLog:
2020-04-28 Tom de Vries <tdevries@suse.de>
* gdb.dwarf2/main-foo.c: New test.
* gdb.dwarf2/struct-with-sig.exp: New file.
I recently stumbled on this code mentioning Linux kernel 2.6.25, and
thought it could be time for some spring cleaning (newer GDBs probably
don't need to supports 12-year old kernels). I then found that the
"legacy" case is probably broken anyway, which gives an even better
motivation for its removal.
In short, this patch removes the configure checks that check if
user_regs_struct contains the fs_base/gs_base fields and adjusts all
uses of the HAVE_STRUCT_USER_REGS_STRUCT_{FS,GS}_BASE macros. The
longer explanation/rationale follows.
Apparently, Linux kernels since 2.6.25 (that's from 2008) have been
reliably providing fs_base and gs_base as part of user_regs_struct.
Commit df5d438e33d7 in the Linux kernel [1] seems related. This means
that we can get these values by reading registers with PTRACE_GETREGS.
Previously, these values were obtained using a separate
PTRACE_ARCH_PRCTL ptrace call.
First, I'm not even sure the configure check was really right in the
first place.
The user_regs_struct used by GDB comes from
/usr/include/x86_64-linux-gnu/sys/user.h (or equivalent on other
distros) and is provided by glibc. glibc has had the fs_base/gs_base
fields in there for a very long time, at least since this commit from
2001 [2]. The Linux kernel also has its version of user_regs_struct,
which I think was exported to user-space at some point. It included the
fs_base/gs_base fields since at least this 2002 commit [3]. In any
case, my conclusion is that the fields were there long before the
aforementioned Linux kernel commit. The kernel commit didn't add these
fields, it only made sure that they have reliable values when obtained
with PTRACE_GETREGS.
So, checking for the presence of the fs_base/gs_base fields in struct
user_regs_struct doesn't sound like a good way of knowing if we can
reliably get the fs_base/gs_base values from PTRACE_GETREGS. My guess
is that if we were using that strategy on a < 2.6.25 kernel, things
would not work correctly:
- configure would find that the user_regs_struct has the fs_base/gs_base
fields (which are probided by glibc anyway)
- we would be reading the fs_base/gs_base values using PTRACE_GETREGS,
for which the kernel would provide unreliable values
Second, I have tried to see how things worked by forcing GDB to not use
fs_base/gs_base from PTRACE_GETREGS (forcing it to use the "legacy"
code, by configuring with
ac_cv_member_struct_user_regs_struct_gs_base=no ac_cv_member_struct_user_regs_struct_fs_base=no
Doing so breaks writing registers back to the inferior. For example,
calling an inferior functions gives an internal error:
(gdb) p malloc(10)
/home/smarchi/src/binutils-gdb/gdb/i387-tdep.c:1408: internal-error: invalid i387 regnum 152
The relevant last frames where this error happens are:
#8 0x0000563123d262fc in internal_error (file=0x563123e93fd8 "/home/smarchi/src/binutils-gdb/gdb/i387-tdep.c", line=1408, fmt=0x563123e94482 "invalid i387 regnum %d") at /home/smarchi/src/binutils-gdb/gdbsupport/errors.cc:55
#9 0x0000563123047d0d in i387_collect_xsave (regcache=0x5631269453f0, regnum=152, xsave=0x7ffd38402a20, gcore=0) at /home/smarchi/src/binutils-gdb/gdb/i387-tdep.c:1408
#10 0x0000563122c69e8a in amd64_collect_xsave (regcache=0x5631269453f0, regnum=152, xsave=0x7ffd38402a20, gcore=0) at /home/smarchi/src/binutils-gdb/gdb/amd64-tdep.c:3448
#11 0x0000563122c5e94c in amd64_linux_nat_target::store_registers (this=0x56312515fd10 <the_amd64_linux_nat_target>, regcache=0x5631269453f0, regnum=152) at /home/smarchi/src/binutils-gdb/gdb/amd64-linux-nat.c:335
#12 0x00005631234c8c80 in target_store_registers (regcache=0x5631269453f0, regno=152) at /home/smarchi/src/binutils-gdb/gdb/target.c:3485
#13 0x00005631232e8df7 in regcache::raw_write (this=0x5631269453f0, regnum=152, buf=0x56312759e468 "@\225\372\367\377\177") at /home/smarchi/src/binutils-gdb/gdb/regcache.c:765
#14 0x00005631232e8f0c in regcache::cooked_write (this=0x5631269453f0, regnum=152, buf=0x56312759e468 "@\225\372\367\377\177") at /home/smarchi/src/binutils-gdb/gdb/regcache.c:778
#15 0x00005631232e75ec in regcache::restore (this=0x5631269453f0, src=0x5631275eb130) at /home/smarchi/src/binutils-gdb/gdb/regcache.c:283
#16 0x0000563123083fc4 in infcall_suspend_state::restore (this=0x5631273ed930, gdbarch=0x56312718cf20, tp=0x5631270bca90, regcache=0x5631269453f0) at /home/smarchi/src/binutils-gdb/gdb/infrun.c:9103
#17 0x0000563123081eed in restore_infcall_suspend_state (inf_state=0x5631273ed930) at /home/smarchi/src/binutils-gdb/gdb/infrun.c:9151
The problem seems to be that amd64_linux_nat_target::store_registers
calls amd64_native_gregset_supplies_p to know whether gregset provides
fs_base. When !HAVE_STRUCT_USER_REGS_STRUCT_FS_BASE,
amd64_native_gregset_supplies_p returns false. store_registers
therefore assumes that it must be an "xstate" register. This is of
course wrong, and that leads to the failed assertion when
i387_collect_xsave doesn't recognize the register.
amd64_linux_nat_target::store_registers could probably be fixed to
handle this case, but I don't think it's worth it, given that it would
only be to support very old kernels.
[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=df5d438e33d7fc914ba9b6e0d6b019a8966c5fcc
[2] https://sourceware.org/git/?p=glibc.git;a=commit;h=c9cf6ddeebb7bb
[3] https://git.kernel.org/pub/scm/linux/kernel/git/tglx/history.git/commit/?id=88e4bc32686ebd0b1111a94f93eba2d334241f68
gdb/ChangeLog:
* configure.ac: Remove check for fs_base/gs_base in
user_regs_struct.
* configure: Re-generate.
* config.in: Re-generate.
* amd64-nat.c (amd64_native_gregset_reg_offset): Adjust.
* amd64-linux-nat.c (amd64_linux_nat_target::fetch_registers,
amd64_linux_nat_target::store_registers, ps_get_thread_area, ): Adjust.
gdbserver/ChangeLog:
* configure.ac: Remove check for fs_base/gs_base in
user_regs_struct.
* configure: Re-generate.
* config.in: Re-generate.
* linux-x86-low.cc (x86_64_regmap, x86_fill_gregset,
x86_store_gregset): Adjust.
Tom Tromey
Tom de Vries
Alan Modra
Simon Marchi
Pedro Alves
Yoshinori Sato
Rainer Orth
Tom Tromey
Philippe Waroquiers
Joel Brobecker
Kevin Buettner
Laurent Morichetti
Tankut Baris Aktemur
Hannes Domani
Andrew Burgess
Kamil Rytarowski
Sterling Augustine