Tom de Vries [Wed, 3 Sep 2025 12:18:35 +0000 (14:18 +0200)]
[gdb/testsuite] Fix clean_restart in gdb.opencl/callfuncs.exp
In test-case gdb.opencl/callfuncs.exp I noticed:
...
clean_restart [standard_testfile $testfile]
...
This doesn't have the desired effect of starting gdb with $testfile because
standard_testfile doesn't return anything.
Fix this by using "clean_restart $testfile".
While we're at it:
- move standard_testfile to the start of the file
- drop the redundant 'set testfile "callfuncs"'
- use standard_testfile .cl to properly define $srcfile
- use $srcfile instead of $testfile.cl
Tested on x86_64-linux, using the demonstrator patch in PR testsuite/33363.
gdb/testsuite: Fix gdb.base/gcore-memory-usage with address sanitizer
The test gdb.base/gcore-memory-usage is meant to show that the memory
requirements of GDB's gcore command don't grow with the memory usage
of the inferior. It was using hardcoded values for memory, but the
values were too small when building GDB with address sanitizer. This
commit fixes one of the failures by increasing the limit on the first
gcore call.
But, rather than just increasing the hardcoded limit for the second
call, we instead save the amount of memory used in the first call and
ensure that the second call doesn't use more memory than the first.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33148 Approved-By: Tom de Vries <tdevries@suse.de>
Alan Modra [Wed, 3 Sep 2025 00:24:50 +0000 (09:54 +0930)]
Disable eh_frame optimisation if code detected in .eh_frame
Fuzzers stress the assembler in ways no sane programmer would ever do.
One x86 oss-fuzz testcase (cleaned up a litte) was:
.sect .debug_frame
call x
.long x,0
.space 1
.long 0,0
The call insn leaves the frag data corresponding to a CIE
uninitialised until later in assembly, leading to reports of
uninitialised data access in ehopt.c:check_eh_frame.
Hack around this problem by noticing an insn has been assembled in
dwarf2_emit_insn. The existing frag has_code can't be used as that
leads to alignment complaints, so add a new segment_info flag.
* subsegs.h (struct segment_info_struct): Move bss and hadone
later. Rename hadone to stab_seen. Add insn_seen bitfield.
* dwarf2dbg.c (dwarf2_emit_insn): Set insn_seen.
* ehopt.c (check_eh_frame): Disable optimisation if insn_seen.
* stabs.c (s_stab_generic): Adjust for hadone rename.
Alan Modra [Wed, 3 Sep 2025 01:29:54 +0000 (10:59 +0930)]
frag_alloc use of obstack_alloc
Avoid the alignment hackery necessary when obstack_alloc is used.
obstack_alloc expands to obstack_blank plus obstack_finish, and the
latter call is where alignment of the tail of the obstack happens.
The docs say obstack_alloc "is invoked almost like malloc", which
implies a fixed size allocation and you don't need other obstack calls
in its use. So I think trying to use obstack_alloc in frag_alloc was
always a poor choice.
* frags.c (frag_alloc): Replace obstack_alloc with obstack_blank.
Alan Modra [Wed, 3 Sep 2025 00:20:17 +0000 (09:50 +0930)]
Explain frag alignment hacks
"the weird alignment hackery" comment doesn't help anyone understand
the code. Explain what is going on. Replace the zero length
obstack_alloc with obstack_finish, which by inspection of obstack.h is
all the zero length alloc does.
* frags.c (frag_alloc): Comment. Replace zero length
obstack_alloc with obstack_finish.
(frag_new): Remove unnecessary obstack_finish.
* write.c (compress_frag, compress_debug): Likewise.
Alan Modra [Tue, 2 Sep 2025 12:15:39 +0000 (21:45 +0930)]
tidy tilegx and tilepro MAX_MEM_FOR_RS_ALIGN_CODE
These weren't wrong, but should use the BUNDLE_SIZE macros, in case
they ever change.
* config/tc-tilegx.h (MAX_MEM_FOR_RS_ALIGN_CODE): Use
TILEGX_BUNDLE_SIZE_IN_BYTES.
* config/tc-tilepro.h (MAX_MEM_FOR_RS_ALIGN_CODE): Use
TILEPRO_BUNDLE_SIZE_IN_BYTES.
Alan Modra [Tue, 2 Sep 2025 09:43:36 +0000 (19:13 +0930)]
visium MAX_MEM_FOR_RS_ALIGN_CODE
Commit 7ca6020a4e52 "tidy target HANDLE_ALIGN" didn't account for
the "fix" amount emitted by visium_handle_align. This didn't show up
as a problem due to frag alignment hiding the error, until I started
messing with struct frag.
Simon Marchi [Tue, 8 Jul 2025 20:54:45 +0000 (16:54 -0400)]
gdb/remote: call target_pre_inferior in remote_target::remote_add_inferior
Since commit 3cb6bc13e328 ("gdb/progspace: add solib_ops pointer in
program_space"), and with the previous patch applied ("gdb/remote: use
scoped_restore_current_program_space in remote_unpush_target"), we get
this failure:
$ make check TESTS="gdb.server/extended-remote-restart.exp" RUNTESTFLAGS="--target_board=native-extended-gdbserver"
When connecting to a remote that has one or more inferior already
running, the remote target (the GDB-side code) tries to re-use existing
GDB inferiors that are unused. The problem is that the program space of
the inferior that gets re-used unexpectedly has its solib_ops set.
I think that the problem is that when connecting to a remote target that
has multiple inferiors, target_pre_inferior only gets called for the
currently selected (client-side) inferior. It happens here:
#0 target_pre_inferior () at /home/smarchi/src/wt/amd/gdb/target.c:2454
#1 0x0000559c832a350a in target_preopen (from_tty=1) at /home/smarchi/src/wt/amd/gdb/target.c:2510
#2 0x0000559c82e1b8f1 in remote_target::open_1 (name=0x50200006eb58 ":2345", from_tty=1, extended_p=1) at /home/smarchi/src/wt/amd/gdb/remote.c:6171
#3 0x0000559c82e18a5d in extended_remote_target::open (name=0x50200006eb58 ":2345", from_tty=1) at /home/smarchi/src/wt/amd/gdb/remote.c:5446
#4 0x0000559c8329a43e in open_target (args=0x50200006eb58 ":2345", from_tty=1, command=0x512000072c40) at /home/smarchi/src/wt/amd/gdb/target.c:839
I think that target_pre_inferior should be called for the other
inferiors that gain execution as a result of connecting to the remote
target, to make sure inferior or program space-specific data from
previous executions gets cleared. target_pre_inferior is what clears
any previous solib_ops.
It is possible to observe the problem by adding this print in
target_pre_inferior:
printf (">>> target_pre_inferior called for inferior %d\n",
current_inferior ()->num);
Then, starting a gdbserver:
$ gdbserver --multi localhost:2345
Then, this gdb command that starts two remote inferiors, disconnects
(leaving gdbserver and the inferiors running), then reconnects:
$ ./gdb -nx --data-directory=data-directory -q \
-ex 'set sysroot /' \
-ex 'target extended-remote :2345' \
-ex 'file testsuite/outputs/gdb.server/extended-remote-restart/extended-remote-restart' \
-ex 'set remote exec-file testsuite/outputs/gdb.server/extended-remote-restart/extended-remote-restart' \
-ex 'b main' \
-ex r \
-ex 'add-inferior' \
-ex 'inferior 2' \
-ex 'file testsuite/outputs/gdb.server/extended-remote-restart/extended-remote-restart' \
-ex 'run' \
-ex 'inferior 1' \
-ex 'disconnect' \
-ex 'echo About to reconnect\n' \
-ex 'target extended-remote :2345'
>>> target_pre_inferior called for inferior 1
Remote debugging using :2345
Reading symbols from /home/smarchi/build/wt/amd/gdb/testsuite/outputs/gdb.server/extended-remote-restart/extended-remote-restart...
Breakpoint 1 at 0x11fc: file /home/smarchi/src/wt/amd/gdb/testsuite/gdb.server/extended-remote-restart.c, line 50.
>>> target_pre_inferior called for inferior 1
Starting program: /home/smarchi/build/wt/amd/gdb/testsuite/outputs/gdb.server/extended-remote-restart/extended-remote-restart
Breakpoint 1, main () at /home/smarchi/src/wt/amd/gdb/testsuite/gdb.server/extended-remote-restart.c:50
50 pid = fork ();
[New inferior 2]
Added inferior 2 on connection 1 (extended-remote :2345)
[Switching to inferior 2 [<null>] (<noexec>)]
Reading symbols from /home/smarchi/build/wt/amd/gdb/testsuite/outputs/gdb.server/extended-remote-restart/extended-remote-restart...
>>> target_pre_inferior called for inferior 2
Starting program: /home/smarchi/build/wt/amd/gdb/testsuite/outputs/gdb.server/extended-remote-restart/extended-remote-restart
Thread 2.1 "extended-remote" hit Breakpoint 1.2, main () at /home/smarchi/src/wt/amd/gdb/testsuite/gdb.server/extended-remote-restart.c:50
50 pid = fork ();
[Switching to inferior 1 [process 2591936] (/home/smarchi/build/wt/amd/gdb/testsuite/outputs/gdb.server/extended-remote-restart/extended-remote-restart)]
[Switching to thread 1.1 (Thread 2591936.2591936)]
#0 main () at /home/smarchi/src/wt/amd/gdb/testsuite/gdb.server/extended-remote-restart.c:50
50 pid = fork ();
Ending remote debugging.
About to reconnect
>>> target_pre_inferior called for inferior 1
Remote debugging using :2345
main () at /home/smarchi/src/wt/amd/gdb/testsuite/gdb.server/extended-remote-restart.c:50
50 pid = fork ();
We can see that target_pre_inferior is only called for inferior 1 when
reconnecting (after the "About to reconnect" message).
After adding the call to target_pre_inferior in remote_add_inferior, we
get (just the last bit):
About to reconnect
>>> target_pre_inferior called for inferior 1
Remote debugging using :2345
>>> target_pre_inferior called for inferior 1
>>> target_pre_inferior called for inferior 2
Reading symbols from /lib/x86_64-linux-gnu/libc.so.6...
(No debugging symbols found in /lib/x86_64-linux-gnu/libc.so.6)
Reading symbols from /lib64/ld-linux-x86-64.so.2...
(No debugging symbols found in /lib64/ld-linux-x86-64.so.2)
main () at /home/smarchi/src/wt/amd/gdb/testsuite/gdb.server/extended-remote-restart.c:50
50 pid = fork ();
The duplicate calls to target_pre_inferior for inferior 1 are due to the
existing call in target_preopen. It might be possible to get rid of it:
with the call I added in remote_target::remote_add_inferior, I presume
it's now unnecessary for the remote target to have the call in
target_preopen as well. But since target_preopen is used by other
targets, I prefer to leave it there to be safe, for the moment. Calling
target_pre_inferior multiple times should not be a problem, as it should
be idempotent.
However, once I added that, test gdb.server/stop-reply-no-thread.exp
started failing, with this in the logs:
target remote localhost:2347
Remote debugging using localhost:2347
Remote 'g' packet reply is too long (expected 560 bytes, got 820 bytes): 000000... <truncated>
It became apparent that the new call to target_pre_inferior would wipe a
previously fetched target description. I fixed that by adding calls to
target_find_description in two callers of remote_add_inferior. I'm not
100% sure of what I'm doing here, but it seems somewhat correct that
when we map a remote inferior to an existing client-side inferior, we
wipe out any previous target description (which would have been left by
a previous execution) and fetch a new one.
The other call to remote_add_inferior is in
extended_remote_target::attach, where there is already a call to
target_find_description shortly after.
The issue is that remote_unpush_target uses
scoped_restore_current_inferior to save the context, which only restores
the current inferior on exit. But it then uses
switch_to_inferior_no_thread, which switches the inferior and the
program space. The program space is therefore left unrestored. This
can leave the current inferior and current program space out of sync.
With two inferiors, let's say we enter with current inferior == 1 and
current program space == 1. When calling switch_to_inferior_no_thread
for inferior 2, we set the current inferior to 2 and current program
space to 2. On exit, only the original inferior is restored, so we end
up with current inferior == 1 and current program space == 2.
The problem can be observed manually by starting two remote inferiors
and disconnecting while inferior 1 is selected:
Then, connecting top-gdb to that gdb, we see the inconsistency:
(top-gdb) p current_inferior_.m_obj.num
$1 = 1
(top-gdb) p current_program_space.num
$2 = 2
When the test tries to connect to a remote target again, GDB maps the
remote inferior to inferior 1, but tries to set the solib_ops of program
space 2, which already has an solib_ops set, causing the internal error.
Fix this by using scoped_restore_current_program_space in addition to
scoped_restore_current_inferior. With this patch applied, we get:
(top-gdb) p current_inferior_.m_obj.num
$1 = 1
(top-gdb) p current_program_space.num
$2 = 1
With this patch, we then hit another internal error, fixed by the
following patch.
H.J. Lu [Mon, 1 Sep 2025 18:00:43 +0000 (11:00 -0700)]
readelf: Report if no GOT section found
Update "readelf --got-contents" to report if no GOT section found.
* readelf.c (process_got_section_contents): Report if no GOT
section found.
* testsuite/binutils-all/readelf-got.d: New file.
* testsuite/binutils-all/readelf.exp: Run readelf-got.
The apparent intent of the original code added in
https://sourceware.org/pipermail/binutils/2012-August/078044.html was
to emit an error message if the instruction was obsolete and only to
emit a deprecation warning if an error hadn't already been emitted.
However, when the insn has not yet been obsoleted, the code would
generate a warning with a (null) message body if the selected CPU was
'any'.
The previous fix for this bug was to remove the support for the
obsoletion message entirely, which was probably the wrong approach. A
better fix is to only call check_obsolete if obs_msg is non-null; we
can use this as a proxy for the instruction not being obsolete on any
architecture.
While we are here, fix an incorrect capitalization in the deprecation
message ('This' to 'this').
Pedro Alves [Fri, 29 Aug 2025 19:05:48 +0000 (20:05 +0100)]
Fix host_file_normalize_mingw
Tom de Vries ran the testsuite on msys2-ucrt64 with mount point map:
...
/bin C:/msys64/usr/bin
/c C:
/ C:/msys64
...
and ran into the problem that host_file_normalize didn't translate:
...
/home/user/gdb/build/gdb/testsuite/temp/n/x
...
into:
...
C:/msys64/home/user/gdb/build/gdb/testsuite/temp/n/x
...
The problem is that host_file_normalize_mingw mishandles a
file/directory under the root mount point. A simpler reproducer is
"/foo". If we add that as a test to
gdb.testsuite/mount-point-map.exp, we see:
For a mount point that ends in /, this line in
host_file_normalize_mingw:
} elseif {[string index $filename $mount_len] eq "/"} {
... is always false, because the character at $mount_len is the one
_after_ the slash.
Notice that the "/" mount point is the only one that ends in "/".
This is even if you try to create one explicitly with a trailing /.
On MSYS2:
$ mount c:/foo /foo/
mount: warning - /foo/ does not exist.
$ mount
C:/foo on /foo type ntfs (binary,user)
...
So fix this by special casing the "/" mount point.
And then... while playing with fixing this, I noticed I had done
something strange with this case:
if {[string length $filename] == $mount_len} {
return "$win_filename/"
The intent was to append the slash when the mount is a drive letter,
like 'cygpath -ma' does:
$ cygpath -ma /c
C:/
Other cases do not get a trailing slash:
$ cygpath -ma /c/foo
C:/foo
I think this is because on Windows, every drive letter has a current
directory, and really "C:" means "current directory of drive letter
C:", not "root of C:". Resolving it to "C:/" makes it unambiguous.
However, I mishandled that in a63213cd374d ('MSYS2+MinGW testing: Unix
<-> Windows path conversion'). The original version of that patch
when I posted it to the mailing list only supported drive mounts,
which turned out incorrect, and then I generalized it to work with all
mount points before it was merged. In the process, I inadvertently
made the code append the slash whenever the input filename matches a
mount exactly, any mount.
I also now noticed that TCL's "file normalize" on Linux always removes
the trailing slash, and since host_file_normalize is an abstraction
for it, I think host_file_normalize_mingw should do the same.
Likewise for duplicate slashes, "file normalize" gets rid of them.
Fix all this in host_file_normalize_mingw, and add corresponding tests
to gdb.testsuite/mount-point-map.exp.
I smoke tested this here with a few of the testcases that required
tweaking in the patch that added host_file_normalize, like
gdb.base/source-dir.exp and gdb.base/fullname.exp and they still pass.
Tom ran gdb.testsuite/mount-point-map.exp on both x86_64-linux and
msys2-ucrt64, and it passed in both cases.
x86/testsuite: Adjust unused FRED and MOVRS tests [PR33348]
The tests mentioned in PR33348 needs different care.
For FRED tests, we could simply remove them since there are
no operands and the tests are the same as AT&T Syntax.
For MOVRS tests, we allowed suffixes for AT&T suffixes although
we could tell the difference according to register operand to
align with legacy mov. Thus, the suffixes tests are needed for
AT&T Syntax while not needed for Intel Syntax. Adjust them
accordingly.
gas/ChangeLog:
PR ld/33348
* testsuite/gas/i386/x86-64-movrs-suffix.d: Describe the
test with more precise.
* testsuite/gas/i386/x86-64-movrs-suffix.s: Remove Intel
Syntax part.
* testsuite/gas/i386/x86-64.exp: Add MOVRS suffix tests.
* testsuite/gas/i386/x86-64-fred-intel.d: Removed.
* testsuite/gas/i386/x86-64-movrs-suffix-intel.d: Ditto.
Lulu Cai [Tue, 26 Aug 2025 09:19:47 +0000 (17:19 +0800)]
LoongArch: Fix incorrect display of FDEs address ranges when using objdump -Wf
When parsing FDEs in `.eh_frame` using `objdump -Wf`, it is necessary to
resolve `BFD_RELOC_LARCH_32_PCREL` to determine the address ranges of
the FDEs. Set the `pcrel_offset` field of `BFD_RELOC_LARCH_32_PCREL` to
help `objdump` correctly compute the address ranges of the FDEs.
Apply the same modification to BFD_RELOC_LARCH_64_PCREL.
Alan Modra [Mon, 1 Sep 2025 01:30:17 +0000 (11:00 +0930)]
Re: readelf: Add --got-contents option
The cris ld testsuite uses readelf -a. The extra output now means
that a number of tests fail. Fix that by not using -a, but rather
the options corresponding to output checked in the dump files.
* testsuite/ld-cris/tls-local-63.d: Replace -a option with -r -s.
Remove now unnecessary #... and superfluous unwind message.
* testsuite/ld-cris/tls-local-64.d: Likewise.
* testsuite/ld-cris/tls-und-38.d: Likewise.
* testsuite/ld-cris/tls-und-42.d: Likewise.
* testsuite/ld-cris/tls-und-46.d: Likewise.
* testsuite/ld-cris/tls-und-50.d: Likewise.
* testsuite/ld-cris/weakref3.d: Replace -a with -S -r -s, and
remove unwind message.
* testsuite/ld-cris/weakref4.d: Likewise.
Tom de Vries [Mon, 1 Sep 2025 07:07:11 +0000 (09:07 +0200)]
[gdb] Fix handling of aborted inferior call
PR gdb/33069 reports the following behavior:
...
$ gdb -q ls -ex starti -ex "b *1"
Reading symbols from ls...
(No debugging symbols found in ls)
Starting program: /usr/bin/ls
Program stopped.
0x00007ffff7fe4f00 in _start () from /lib64/ld-linux-x86-64.so.2
Breakpoint 1 at 0x1
(gdb) p (int)strlen("abc")
Warning:
Cannot insert breakpoint 1.
Cannot access memory at address 0x1
Command aborted.
An error occurred while in a function called from GDB.
Evaluation of the expression containing the function
(malloc@plt) will be abandoned.
When the function is done executing, GDB will silently stop.
[1]+ Stopped gdb -q ls -ex starti -ex "b *1"
$ fg
gdb -q ls -ex starti -ex "b *1"
(gdb)
...
with gdb being unresponsive to further input.
PR gdb/33068 reports a similar problem, but using gdbserver, and in that case
gdb doesn't go into the background, but is likewise unresponsive.
This is a regression since commit b1c0ab20809 ("gdb: avoid double stop after
failed breakpoint condition check"), and consequently since release gdb 14.1.
The commit changed this in run_inferior_call:
...
if (current_ui->prompt_state == PROMPT_BLOCKED)
- current_ui->unregister_file_handler ();
- else
- current_ui->register_file_handler ();
+ {
+ if (call_thread->thread_fsm ()->finished_p ())
+ async_disable_stdin ();
+ else
+ async_enable_stdin ();
+ }
...
which means current_ui->register_file_handler is no longer called in the
current_ui->prompt_state == PROMPT_NEEDED case.
Fix this by:
- restoring this behavior, fixing the unresponsiveness, and
- adding target_terminal::ours alongside it, fixing the problem that gdb goes
into the background.
Add a new test-case gdb.base/infcall-failure-2.exp, a regression test for the
unresponsiveness issue. The problem of gdb going into the background did not
reproduce in the test-case.
Tested on x86_64-linux.
Reviewed-By: Keith Seitz <keiths@redhat.com>
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33068
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33069
Rainer Orth [Sun, 31 Aug 2025 10:14:36 +0000 (12:14 +0200)]
ld: Move Solaris/sparcv9 TEXT_START_ADDR to elf64_sparc_sol2.sh
While looking at the Solaris versions of the program header p_vaddr and
p_align values of the text and data segments, I noticed that the
Solaris/sparcv9 version of TEXT_START_ADDR is defined in a shared file.
Since there's a Solaris/sparcv9 specific file now
(ld/emulparams/elf64_sparc_sol2.sh), it seems cleaner to move it there.
Tested on {sparcv9,sparc}-sun-solaris2.11 and
{sparc64,sparc}-unknown-linux-gnu.
Simon Marchi [Fri, 29 Aug 2025 20:05:27 +0000 (16:05 -0400)]
gdb/solib-svr4: update default debug base in svr4_solib_ops::current_sos
Commit d33a66a31134 ("gdb/solib-svr4: fix wrong namespace id for dynamic
linker") regressed test gdb.base/break-probes.exp with the native-gdbserver
board:
Running /home/simark/src/binutils-gdb/gdb/testsuite/gdb.base/break-probes.exp ...
FAIL: gdb.base/break-probes.exp: run til our library loads (the program exited)
FAIL: gdb.base/break-probes.exp: call (int) foo(23)
In the logs, we see this:
Stopped due to shared library event:
Inferior unloaded target:/lib64/ld-linux-x86-64.so.2
Inferior loaded target:/lib64/ld-linux-x86-64.so.2
When we should see this:
Stopped due to shared library event (no libraries added or removed)
In the unexpected output, GDB claims that the inferior unloaded and then
loaded the dynamic linker. This is obviously not true.
Commit d33a66a31134 changed the svr4_same function to consider the debug
bases the solibs come from. Two solibs with the same inferior address but
different debug base (such as the multiple solibs representing the dynamic
linker in all the namespaces) now compare unequal.
That commit also introduced a mechanism to update the debug base of an
existing solib (more precisely, field lm_info_svr4::debug_base) when that
value becomes known. The solib for the dynamic linker view in the default
namespace starts with a debug base of 0, and is then changed to have the
real debug base address later on.
With the particular code path taken when connecting to a remote target,
nothing triggers the update of the debug base of the dynamic linker solib
initially created with a debug base of 0. So when
svr4_solib_ops::current_sos returns a list with an solib for the dynamic
linker with the real debug base value, the core sees this as an unload and
a load.
This happens specifically when debuggin remotely, because,
svr4_solib_ops::current_sos_direct takes the "using_xfer" branch, which
doesn't do any svr4_solib_ops::default_debug_base call. In local, we don't
take that branch, which leads us to a call to default_debug_base.
The way I propose to fix it is to add a call to
svr4_solib_ops::default_debug_base at the beginning of
svr4_solib_ops::current_sos. The rationale to put it there is that if the
core is requesting a fresh list of libraries, and then compare that list
with what it had previously, then we better make sure that the core's list
has received the debug base update, if one is needed.
Change-Id: If09c5a7b3d956e18d4b9514466226267c85f12a6 Approved-by: Kevin Buettner <kevinb@redhat.com>
The GCSPR is almost always updated implicitly by the hardware, so the
compiler doesn't generate DWARF unwind information for it. Therefore add
an unwinding function that calculates the value of the GCSPR in the
previous frame based on its value in this frame. Some sanity checking is
done by confirming that the calculated value is within a Guarded Control
Stack memory area.
This function is the same as amd64_linux_dwarf2_prev_ssp, written by
Christina Schimpe to unwind Intel's SSP register.
The gdb.arch/aarch64-gcs-return.exp testcase is lightly adapted from
gdb.arch/amd64-shadow-stack-cmds.exp.
Reviewed-By: Christina Schimpe <christina.schimpe@intel.com> Approved-By: Luis Machado <luis.machado@arm.com>
GDB: aarch64-linux: Implement GCS support in displaced stepping
When doing displaced step on a branch and link instruction with the Guarded
Control Stack enabled, it's necessary to manually push and pop the GCS
entry for the function call since GDB writes a simple branch instruction
rather than a branch and link instruction in the displaced step buffer.
The testcase exercises GCS with displaced stepping by putting the
breakpoint on the bl instruction to force GDB to copy it to the
displaced stepping buffer. In this situation GDB needs to manually
manage the Guarded Control Stack.
Reviewed-By: Christina Schimpe <christina.schimpe@intel.com> Approved-By: Luis Machado <luis.machado@arm.com>
The signal frame can have a GCS context, so teach GDB how to use it.
Also, there's a new SEGV sigcode when the inferior does an illegal
memory access in the Guarded Control Stack, so display a message when
that is the case.
Reviewed-By: Christina Schimpe <christina.schimpe@intel.com> Approved-By: Luis Machado <luis.machado@arm.com>
GDB, gdbserver: aarch64-linux: Initial Guarded Control Stack support
Add the org.gnu.gdb.aarch64.gcs feature with the GCSPR register, and the
org.gnu.gdb.aarch64.gcs.linux feature with "registers" to represent the
Linux kernel ptrace and prctl knobs that enable and lock specific GCS
functionality.
This code supports GCS only in Linux userspace applications, so the
GCSPR that is exposed is the one at EL0.
Also, support for calling inferior functions is enabled by adding an
implementation for the shadow_stack_push gdbarch method.
If for some reason a target description contains the
org.gnu.gdb.aarch64.gcs feature but not the
org.gnu.gdb.aarch64.gcs.linux feature then GCS support is disabled and
GDB continues the debugging session. Features that need GCS
support (for example, calling inferior functions) will not work and the
inferior will get a segmentation fault signal instead. There's a
testcase for this scenario but it only checks the native debugging case,
even though in practice this problem would only occur in remote
debugging with a broken stub or gdbserver. I tested manually with a
gdbserver hacked to send a broken target description and it worked as
described.
Testcases gdb.arch/aarch64-gcs.exp, gdb.arch/aarch64-gcs-core.exp and
gdb.arch/aarch64-gcs-wrong-tdesc.exp are included to cover the added
functionality.
Reviewed-By: Christina Schimpe <christina.schimpe@intel.com> Approved-By: Luis Machado <luis.machado@arm.com>
Simon Marchi [Thu, 28 Aug 2025 15:10:51 +0000 (11:10 -0400)]
gdb/objfiles: use filtered_iterator as objfile::section_iterator
objfile::section_iterator looks like a good candidate to be implemented
with filtered_iterator. Following the enhancements to filtered_iterator
in the previous patch, it's pretty straighforward.
I removed the non-const version of objfile::sections, because it didn't
seem useful to have the two methods returning the exact same type and
value. Having just the const version achieves the same thing.
Change-Id: I2f29c2fb3f95605cb816cc1ff8935c10e0496052 Approved-By: Tom Tromey <tom@tromey.com>
- Give filtered_iterator a constructor where the caller provides
already constructed begin and end iterators. filtered_iterator
currently assumes that default-constructing a BaseIterator will
produce a valid "end" iterator. This is not the case if BaseIterator
is a pointer. The caller needs to pass in the end of the array /
region to iterate on as the end.
The compiler would complain that it's not possible to apply `::` to
type `BaseIterator` (aka `Foo *`). Use std::iterator_traits to fix
it [1].
- Similarly, the compiler would complain about the use of
`BaseIterator::operator*` in the return type of
`filtered_iterator::operator*`. Fix this by using `decltype(auto)`
as the return type. This lets the compiler deduce the return type
from the return statement. Unlike `auto`, `decltype(auto)` perfectly
preserves the "cvref-ness" of the deduced return type. If the return
expression yields a `Foo &`, then the function will return a `Foo &`
(which is what we want), whereas it would return a `Foo` if we used
just `auto`.
Improve the filtered_iterator unit tests to run the same tests but with
pointers as iterators. Because the filtered_iterator objects are
initialized differently in the two scenarios, I chose to copy the
existing code and adapt it. It would probably be possible to add a
layer of abstraction to avoid code duplication, but it would end up more
complicated and messy. If we ever add a third scenario, we can revisit
that.
gdb: Enable displaced stepping with shadow stack on amd64 linux.
Currently, if displaced stepping is active and the single stepped instruction
is a call instruction, the return address atop the stack is the address
following the copied instruction. However, to allow normal program execution
it has to be the address following the original instruction. Due to that
reason, the return address is corrected in amd64_displaced_step_fixup and
i386_displaced_step_fixup.
For programs that are shadow-stack enabled we see a control-protection
exception, as the address on the shadow stack does not match the address
atop the stack.
Fix this by correcting the shadow stack top address as well.
Approved-By: Andrew Burgess <aburgess@redhat.com> Approved-By: Luis Machado <luis.machado@arm.com> Reviewed-By: Eli Zaretskii <eliz@gnu.org>
gdb: Implement amd64 linux shadow stack support for inferior calls.
This patch enables inferior calls to support Intel's Control-Flow
Enforcement Technology (CET), which provides the shadow stack feature
for the x86 architecture.
Following the restriction of the linux kernel, enable inferior calls
for amd64 only.
Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Reviewed-By: Eli Zaretskii <eliz@gnu.org> Approved-By: Luis Machado <luis.machado@arm.com> Approved-By: Andrew Burgess <aburgess@redhat.com>
gdb, gdbarch: Enable inferior calls for shadow stack support.
Inferior calls in GDB reset the current PC to the beginning of the function
that is called. As no call instruction is executed the new return address
needs to be pushed to the shadow stack and the shadow stack pointer needs
to be updated.
This commit adds a new gdbarch method to push an address on the shadow
stack. The method is used to adapt the function 'call_function_by_hand_dummy'
for inferior call shadow stack support.
Reviewed-By: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Approved-By: Luis Machado <luis.machado@arm.com> Approved-By: Andrew Burgess <aburgess@redhat.com>
gdb: Handle shadow stack pointer register unwinding for amd64 linux.
Unwind the $pl3_ssp register.
We now have an updated value for the shadow stack pointer when
moving up or down the frame level. Note that $pl3_ssp can
become unavailable when moving to a frame before the shadow
stack enablement. In the example below, shadow stack is enabled
in the function 'call1'. Thus, when moving to a frame level above
the function, $pl3_ssp will become unavaiable.
Following the restriction of the linux kernel, implement the unwinding
for amd64 linux only.
Before this patch:
~~~
Breakpoint 1, call2 (j=3) at sample.c:44
44 return 42;
(gdb) p $pl3_ssp
$1 = (void *) 0x7ffff79ffff8
(gdb) up
55 call2 (3);
(gdb) p $pl3_ssp
$2 = (void *) 0x7ffff79ffff8
(gdb) up
68 call1 (43);
(gdb) p $pl3_ssp
$3 = (void *) 0x7ffff79ffff8
~~~
After this patch:
~~~
Breakpoint 1, call2 (j=3) at sample.c:44
44 return 42;
(gdb) p $pl3_ssp
$1 = (void *) 0x7ffff79ffff8
(gdb) up
55 call2 (3);
(gdb) p $pl3_ssp
$2 = (void *) 0x7ffff7a00000
(gdb) up
68 call1 (43i);
(gdb) p $pl3_ssp
$3 = <unavailable>
~~~
As we now have an updated value for each selected frame, the
return command is now enabled for shadow stack enabled programs, too.
We therefore add a test for the return command and shadow stack support,
and for an updated shadow stack pointer after a frame level change.
Reviewed-By: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Approved-By: Luis Machado <luis.machado@arm.com> Approved-By: Andrew Burgess <aburgess@redhat.com>
gdb: amd64 linux coredump support with shadow stack.
Intel's Control-Flow Enforcement Technology (CET) provides the shadow
stack feature for the x86 architecture.
This commit adds support to write and read the shadow-stack node in
corefiles. This helps debugging return address violations post-mortem.
The format is synced with the linux kernel commit "x86: Add PTRACE
interface for shadow stack". As the linux kernel restricts shadow
stack support to 64-bit, apply the fix for amd64 only.
Co-Authored-By: Christina Schimpe <christina.schimpe@intel.com> Reviewed-By: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Approved-By: Luis Machado <luis.machado@arm.com> Approved-By: Andrew Burgess <aburgess@redhat.com>
---
The code and testcase are lightly adapted from:
[PATCH v3 5/9] GDB, gdbserver: aarch64-linux: Initial Guarded Control Stack support
gdb, gdbserver: Add support of Intel shadow stack pointer register.
This patch adds the user mode register PL3_SSP which is part of the
Intel(R) Control-Flow Enforcement Technology (CET) feature for support
of shadow stack.
For now, only native and remote debugging support for shadow stack
userspace on amd64 linux are covered by this patch including 64 bit and
x32 support. 32 bit support is not covered due to missing Linux kernel
support.
This patch requires fixing the test gdb.base/inline-frame-cycle-unwind
which is failing in case the shadow stack pointer is unavailable.
Such a state is possible if shadow stack is disabled for the current thread
but supported by HW.
This test uses the Python unwinder inline-frame-cycle-unwind.py which fakes
the cyclic stack cycle by reading the pending frame's registers and adding
them to the unwinder:
~~~
for reg in pending_frame.architecture().registers("general"):
val = pending_frame.read_register(reg)
unwinder.add_saved_register(reg, val)
return unwinder
~~~
However, in case the python unwinder is used we add a register (pl3_ssp) that is
unavailable. This leads to a NOT_AVAILABLE_ERROR caught in
gdb/frame-unwind.c:frame_unwind_try_unwinder and it is continued with standard
unwinders. This destroys the faked cyclic behavior and the stack is
further unwinded after frame 5.
In the working scenario an error should be triggered:
~~~
bt
0 inline_func () at /tmp/gdb.base/inline-frame-cycle-unwind.c:49^M
1 normal_func () at /tmp/gdb.base/inline-frame-cycle-unwind.c:32^M
2 0x000055555555516e in inline_func () at /tmp/gdb.base/inline-frame-cycle-unwind.c:45^M
3 normal_func () at /tmp/gdb.base/inline-frame-cycle-unwind.c:32^M
4 0x000055555555516e in inline_func () at /tmp/gdb.base/inline-frame-cycle-unwind.c:45^M
5 normal_func () at /tmp/gdb.base/inline-frame-cycle-unwind.c:32^M
Backtrace stopped: previous frame identical to this frame (corrupt stack?)
(gdb) PASS: gdb.base/inline-frame-cycle-unwind.exp: cycle at level 5: backtrace when the unwind is broken at frame 5
~~~
To fix the Python unwinder, we simply skip the unavailable registers.
Also it makes the test gdb.dap/scopes.exp fail. The shadow stack feature is
disabled by default, so the pl3_ssp register which is added with my CET
shadow stack series will be shown as unavailable and we see a TCL error:
~~
>>> {"seq": 12, "type": "request", "command": "variables", "arguments": {"variablesReference": 2, "count": 85}}
Content-Length: 129^M
^M
{"request_seq": 12, "type": "response", "command": "variables", "success": false, "message": "value is not available", "seq": 25}FAIL: gdb.dap/scopes.exp: fetch all registers success
ERROR: tcl error sourcing /tmp/gdb/testsuite/gdb.dap/scopes.exp.
ERROR: tcl error code TCL LOOKUP DICT body
ERROR: key "body" not known in dictionary
while executing
"dict get $val body variables"
(file "/tmp/gdb/testsuite/gdb.dap/scopes.exp" line 152)
invoked from within
"source /tmp/gdb/testsuite/gdb.dap/scopes.exp"
("uplevel" body line 1)
invoked from within
"uplevel #0 source /tmp/gdb/testsuite/gdb.dap/scopes.exp"
invoked from within
"catch "uplevel #0 source $test_file_name" msg"
UNRESOLVED: gdb.dap/scopes.exp: testcase '/tmp/gdb/testsuite/gdb.dap/scopes.exp' aborted due to Tcl error
~~
I am fixing this by enabling the test for CET shadow stack, in case we
detect that the HW supports it:
~~~
# If x86 shadow stack is supported we need to configure GLIBC_TUNABLES
# such that the feature is enabled and the register pl3_ssp is
# available. Otherwise the reqeust to fetch all registers will fail
# with "message": "value is not available".
if { [allow_ssp_tests] } {
append_environment GLIBC_TUNABLES "glibc.cpu.hwcaps" "SHSTK"
}
~~~
Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Reviewed-By: Eli Zaretskii <eliz@gnu.org> Approved-By: Luis Machado <luis.machado@arm.com> Approved-By: Andrew Burgess <aburgess@redhat.com>
gdb, gdbserver: Use xstate_bv for target description creation on x86.
The XSAVE function set is organized in state components, which are a set of
registers or parts of registers. So-called XSAVE-supported features are
organized using state-component bitmaps, each bit corresponding to a
single state component.
The Intel Software Developer's Manual uses the term xstate_bv for a
state-component bitmap, which is defined as XCR0 | IA32_XSS. The control
register XCR0 only contains a state-component bitmap that specifies user state
components, while IA32_XSS contains a state-component bitmap that specifies
supervisor state components.
Until now, XCR0 is used as input for target description creation in GDB.
However, a following patch will add userspace support for the CET shadow
stack feature by Intel. The CET state is configured in IA32_XSS and consists
of 2 state components:
- State component 11 used for the 2 MSRs controlling user-mode
functionality for CET (CET_U state)
- State component 12 used for the 3 MSRs containing shadow-stack pointers
for privilege levels 0-2 (CET_S state).
Reading the CET shadow stack pointer register on linux requires a separate
ptrace call using NT_X86_SHSTK. To pass the CET shadow stack enablement
state we would like to pass the xstate_bv value instead of xcr0 for target
description creation. To prepare for that, we rename the xcr0 mask
values for target description creation to xstate_bv. However, this
patch doesn't add any functional changes in GDB.
Future states specified in IA32_XSS such as CET will create a combined
xstate_bv_mask including xcr0 register value and its corresponding bit in
the state component bitmap. This combined mask will then be used to create
the target descriptions.
Reviewed-By: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Approved-By: Luis Machado <luis.machado@arm.com>
gdbserver: Add assert in x86_linux_read_description.
On x86 the PTRACE_GETREGSET request is currently only used for the xstate regset.
The size of the xstate regset is initialized to 0 such that it can be reset to
the appropriate size once we know it is supported for the current target
in x86_linux_read_description.
However, this configuration would not just affect the xstate regset but any regset
with PTRACE_GETREGSET request that is added in the future. The new regset would be
misconfigured with the xstate regset size. To avoid this we add an assert for
unsupported regsets and check explicitly for the note type of the register set.
Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Approved-By: Luis Machado <luis.machado@arm.com>
gdbserver: Add optional runtime register set type.
Some register sets can be activated and deactivated by the OS during the runtime of
a process. One example register is the Intel CET shadow stack pointer. This patch
adds a new type of register set to handle such cases. We shouldn't deactivate these
regsets and should not show a warning if the register set is not active but supported
by the kernel. However, it is safe to deactivate them, if they are unsupported by the
kernel. To differentiate those scenarios we can use the errno returned by the ptrace
call.
Reviewed-by: Thiago Jung Bauermann <thiago.bauermann@linaro.org> Approved-By: Luis Machado <luis.machado@arm.com>
We need it for testing coredump files, too. So include it in this patch series.
Abridged-by: Christina Schimpe <christina.schimpe@intel.com> Approved-By: Luis Machado <luis.machado@arm.com> Approved-By: Andrew Burgess <aburgess@redhat.com>
---
This is the patch mentioned above:
Simon Marchi [Wed, 27 Aug 2025 14:38:13 +0000 (10:38 -0400)]
gdb/objfiles: make objfile::sections yield references
I wrote this as a preparatory patch while attempting to make
objfile::section_iterator use filtered_iterator. It turned out not so
easy, so I have put it aside for now. But now I have this patch, so I
thought I'd send it by itself.
Since the `obj_section *` yielded by the iterator can't be nullptr, I
think it makes sense for the iterator to yield references instead.
Just like you would get if you iterated on an std::vector<obj_section>.
Tom de Vries [Fri, 29 Aug 2025 15:31:58 +0000 (17:31 +0200)]
[gdb/testsuite] Fix overlapping CUs in gdb.dwarf2/dw2-linkage-name-trust.exp
When running test-case gdb.dwarf2/dw2-linkage-name-trust.exp with target board
cc-with-gdb-index, I get:
...
(gdb) file dw2-linkage-name-trust^M
Reading symbols from dw2-linkage-name-trust...^M
warning: .gdb_index address table has a range (0x4006ac - 0x4006cc) that \
overlaps with an earlier range, ignoring .gdb_index^M
(gdb) delete breakpoints^M
...
Fix this by compiling with nodebug.
Tested on aarch64-linux.
Approved-By: Tom Tromey <tom@tromey.com>
PR testsuite/33315
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33315
Tom de Vries [Fri, 29 Aug 2025 15:31:58 +0000 (17:31 +0200)]
[gdb/testsuite] Fix overlapping CUs in gdb.dwarf2/dw2-entry-points.exp
When running test-case gdb.dwarf2/dw2-entry-points.exp with target board
cc-with-gdb-index, I get:
...
(gdb) file dw2-entry-points^M
Reading symbols from dw2-entry-points...^M
warning: .gdb_index address table has a range (0x40066c - 0x4006e4) that \
overlaps with an earlier range, ignoring .gdb_index^M
(gdb) delete breakpoints^M
...
Fix this by copying function bar_helper to barso_helper, and using it where
appropriate.
Tested on aarch64-linux.
Approved-By: Tom Tromey <tom@tromey.com>
PR testsuite/33315
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=33315
Tom describes the issue clearly in the above thread, here's what he
said:
Once in a while, when running test-case gdb.base/bp-cmds-continue-ctrl-c.exp,
I run into:
...
Breakpoint 2, foo () at bp-cmds-continue-ctrl-c.c:23^M
23 usleep (100);^M
^CFAIL: $exp: run: stop with control-c (unexpected) (timeout)
FAIL: $exp: run: stop with control-c
...
This is PR python/32167, observed both on x86_64-linux and powerpc64le-linux.
This is not a timeout due to accidental slowness, gdb actually hangs.
The backtrace at the hang is (on cfarm120 running AlmaLinux 9.6):
...
(gdb) bt
#0 0x00007fffbca9dd94 in __lll_lock_wait () from
/lib64/glibc-hwcaps/power10/libc.so.6
#1 0x00007fffbcaa6ddc in pthread_mutex_lock@@GLIBC_2.17 () from
/lib64/glibc-hwcaps/power10/libc.so.6
#2 0x000000001067aee8 in __gthread_mutex_lock ()
at /usr/include/c++/11/ppc64le-redhat-linux/bits/gthr-default.h:749
#3 0x000000001067afc8 in __gthread_recursive_mutex_lock ()
at /usr/include/c++/11/ppc64le-redhat-linux/bits/gthr-default.h:811
#4 0x000000001067b0d4 in std::recursive_mutex::lock ()
at /usr/include/c++/11/mutex:108
#5 0x000000001067b380 in std::lock_guard<std::recursive_mutex>::lock_guard ()
at /usr/include/c++/11/bits/std_mutex.h:229
#6 0x0000000010679d3c in set_quit_flag () at gdb/extension.c:865
#7 0x000000001066b6dc in handle_sigint () at gdb/event-top.c:1264
#8 0x00000000109e3b3c in handler_wrapper () at gdb/posix-hdep.c:70
#9 <signal handler called>
#10 0x00007fffbcaa6d14 in pthread_mutex_lock@@GLIBC_2.17 () from
/lib64/glibc-hwcaps/power10/libc.so.6
#11 0x000000001067aee8 in __gthread_mutex_lock ()
at /usr/include/c++/11/ppc64le-redhat-linux/bits/gthr-default.h:749
#12 0x000000001067afc8 in __gthread_recursive_mutex_lock ()
at /usr/include/c++/11/ppc64le-redhat-linux/bits/gthr-default.h:811
#13 0x000000001067b0d4 in std::recursive_mutex::lock ()
at /usr/include/c++/11/mutex:108
#14 0x000000001067b380 in std::lock_guard<std::recursive_mutex>::lock_guard ()
at /usr/include/c++/11/bits/std_mutex.h:229
#15 0x00000000106799cc in set_active_ext_lang ()
at gdb/extension.c:775
#16 0x0000000010b287ac in gdbpy_enter::gdbpy_enter ()
at gdb/python/python.c:232
#17 0x0000000010a8e3f8 in bpfinishpy_handle_stop ()
at gdb/python/py-finishbreakpoint.c:414
...
What happens here is the following:
- the gdbpy_enter constructor attempts to set the current extension language
to python using set_active_ext_lang
- set_active_ext_lang attempts to lock ext_lang_mutex
- while doing so, it is interrupted by sigint_wrapper (the SIGINT handler),
handling a SIGINT
- sigint_wrapper calls handle_sigint, which calls set_quit_flag, which also
tries to lock ext_lang_mutex
- since std::recursive_mutex::lock is not async-signal-safe, things go wrong,
resulting in a hang.
The hang bisects to commit 8bb8f834672 ("Fix gdb.interrupt race"), which
introduced the lock, making PR python/32167 a regression since gdb 15.1.
Commit 8bb8f834672 fixes PR dap/31263, a race reported by ThreadSanitizer:
...
WARNING: ThreadSanitizer: data race (pid=615372)
Read of size 1 at 0x00000328064c by thread T19:
#0 set_active_ext_lang(extension_language_defn const*) gdb/extension.c:755
#1 scoped_disable_cooperative_sigint_handling::scoped_disable_cooperative_sigint_handling()
gdb/extension.c:697
#2 gdbpy_interrupt gdb/python/python.c:1106
#3 cfunction_vectorcall_NOARGS <null>
Previous write of size 1 at 0x00000328064c by main thread:
#0 scoped_disable_cooperative_sigint_handling::scoped_disable_cooperative_sigint_handling()
gdb/extension.c:704
#1 fetch_inferior_event() gdb/infrun.c:4591
...
Location is global 'cooperative_sigint_handling_disabled' of size 1 at 0x00000328064c
...
SUMMARY: ThreadSanitizer: data race gdb/extension.c:755 in \
set_active_ext_lang(extension_language_defn const*)
...
The problem here is that gdb.interrupt is called from a worker thread, and its
implementation, gdbpy_interrupt races with the main thread on some variable.
The fix presented here is based on the fix that Tom proposed, but
fills in the missing Mingw support.
The problem is basically split into two: hosts that support unix like
signals, and Mingw, which doesn't support signals.
For signal supporting hosts, I've adopted the approach that Tom
suggests, gdbpy_interrupt uses kill() to send SIGINT to the GDB
process. This is then handled in the main thread as if the user had
pressed Ctrl+C. For these hosts no locking is required, so the
existing lock is removed. However, everywhere the lock currently
exists I've added an assert:
gdb_assert (is_main_thread ());
If this assert ever triggers then we're setting or reading the quit
flag on a worker thread, this will be a problem without the mutex.
For Mingw, the current mutex is retained. This is fine as there are
no signals, so no chance of the mutex acquisition being interrupted by
a signal, and so, deadlock shouldn't be an issue.
To manage the complexity of when we need an assert, and when we need
the mutex, I've created 'struct ext_lang_guard', which can be used as
a RAII object. This object either performs the assertion check, or
acquires the mutex, depending on the host.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=32167 Co-Authored-By: Tom de Vries <tdevries@suse.de> Approved-By: Tom Tromey <tom@tromey.com>
H.J. Lu [Thu, 28 Aug 2025 21:15:18 +0000 (14:15 -0700)]
readelf: Add --got-contents option
Add --got-contents option to readelf, inspired by the -G option on Solaris,
to display contents of GOT sections:
$ readelf --got-contents libfoo.so
Global Offset Table '.got' contains 1 entry:
Index: Address Reloc Sym. Name + Addend/Value
0: 000000200340 R_X86_64_GLOB_DAT foo + 0
Global Offset Table '.got.plt' contains 4 entries:
Index: Address Reloc Sym. Name + Addend/Value
0: 000000200348 200220
1: 000000200350 0
2: 000000200358 0
3: 000000200360 R_X86_64_JUMP_SLO bar + 0
When --got-content options are used:
1. Allocate an array, all_relocations, to hold all relocations.
2. Update dump_relr_relocations and dump_relocations to scan relocations
and cache them in all_relocations. Don't display relocations if not
requested.
3. Add process_got_section_contents to display contents of GOT sections
by matching the GOT entry offset against the cached relocations.
4. Update process_mips_specific to only display the GOT related contents
for --got-contents.
binutils/
* NEWS: Mention "readelf --got-contents".
* readelf.c (do_got_section_contents): New.
(elf_relocation): Likewise.
(all_relocations_root): Likewise.
(all_relocations): Likewise.
(all_relocations_count): Likewise.
(update_all_relocations): Likewise.
(dump_relr_relocations): Add a bool argument to indicate if
relocations should be displayed. Populate all_relocations if
do_got_section_contents is true.
(dump_relocations): Likewise.
(long_option_values): Add OPTION_GOT_CONTENTS.
(options): Add --got-contents.
(usage): Show --got-contents.
(parse_args): Support --got-contents.
(display_relocations): Add a bool argument, dump_reloc, to
indicate if relocations should be displayed. Call
update_all_relocations. Pass dump_reloc to dump_relr_relocations
and dump_relocations.
(process_relocs): Check do_got_section_contents. Handle
do_got_section_contents for dynamic relocations.
(process_section_contents): Pass true to display_relocations.
(process_mips_specific): Add a bool argument, dump_got, to
indicate if only the GOT related contents should be displayed.
Display all MIPS specific information if dump_got is false.
(elf_relocation_cmp): New.
(display_elf_relocation_at): Likewise.
(process_got_section_contents): Likewise.
(process_object): Call process_got_section_contents.
* doc/binutils.texi: Document --got-contents.
x86: add "udb" opcode (permanent official #UD in 64-bit mode)
The opcode D6 has been officially reserved as a single-byte permanent
undefined (#UD) opcode in 64-bit mode with the mnemonic UDB. This is
already the behavior of all known 64-bit implementations; this is thus
merely an official statement of forward compatibility and the
assignment of a mnemonic.
This will be documented in the next version of the Intel Software
Developer's Manual; in the meantime I DO speak officially for Intel on
this issue.
The x86 Advisory Council has ratified this decision, and so it is
expected to be honored across vendors, but I obviously cannot make any
official statement on any other vendor's behalf.
I am covered by the Intel-FSF copyright assignment for binutils.
Signed-off-by: H. Peter Anvin (Intel) <hpa@zytor.com>
Simon Marchi [Mon, 25 Aug 2025 17:02:12 +0000 (13:02 -0400)]
gdb/gdb-gdb.gdb.in: skip gdb::ref_ptr<.*>::get
I think it's uninteresting to step into gdb::ref_ptr::get, so add a skip
entry for it. I am adding just one to get the party started, but there
are certainly more like this that we could skip.
Change-Id: Ib074535c96a62137de63bbe58ff168a1e913688f Approved-By: Tom Tromey <tom@tromey.com>
Simon Marchi [Mon, 25 Aug 2025 15:44:22 +0000 (11:44 -0400)]
gdb/testsuite: use gdb_test_no_output when dumping in gdb.base/dump.exp
I don't know if this is true on all platforms, but from what I can see
on Linux, the dump commands don't output anything. Use
gdb_test_no_output, which should be a bit more robust than checking for
some specific error patterns.
Change-Id: Idc82298c4752ba7808659dfea2f8324c8a97052d Approved-By: Tom Tromey <tom@tromey.com>
Fix documentation of -list-[target-]features results
The manual claims that the -list-features and -list-target-features MI
commands return their result in a field named "result". The field is
actually named "features", and always has been since the introduction of
these commands in 084344d and c6ebd6c. See mi_cmd_list_features and
mi_cmd_list_target_features in gdb/mi/mi-main.c.
testsuite: add untested in case OS corefile is not found
Even though the core_find proc will log a warning, it's better to log
"untested" and then terminate the test. This will help to avoid
silently skipped tests, when running the testsuite. Most of the tests
already do that. This patch adds the missing ones.
Approved-By: Luis Machado <luis.machado.foss@gmail.com>
gdb/python: check return value of PyObject_New in all cases
I missed a call to PyObject_New in python/py-disasm.c, which this
commit addresses.
Unlike the previous commit, the call to PyObject_New in py-disasm.c is
contained within the scoped_disasm_info_object class, which makes it
harder to check for NULL and return.
So in this commit I've rewritten the scoped_disasm_info_object class,
moving the call to PyObject_New out into gdbpy_print_insn, which is
the only place that scoped_disasm_info_object was being used.
As scoped_disasm_info_object is no longer responsible for creating the
underlying Python object, I figured that I might as well move the
initialisation of that object out of scoped_disasm_info_object too.
With that done, the scoped_disasm_info_object now has just one task,
invalidating the existing disasm_info_object at the end of the scope.
So I renamed scoped_disasm_info_object to
scoped_invalidate_disasm_info, which reflects its only task.
I made a couple of other small adjustments that were requested during
review, these are both in the same code area: updating
disasm_info_fill to take an object reference rather than a pointer,
and removing the local variable insn_disas_obj from gdbpy_print_insn,
and inline its value at the one place it was used.
There should be no user visible changes after this commit. Except for
the PyObject_New call, which now has proper error checking. But in
the working case, nothing should have changed.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Tom de Vries [Thu, 28 Aug 2025 09:36:29 +0000 (11:36 +0200)]
[gdb/testsuite] Use build_executable in gdb.tui/tui-missing-src.exp
While looking at test-case gdb.tui/tui-missing-src.exp I noticed that
gdb_compile is used to compile multiple sources:
...
if { [gdb_compile "${srcfiles}" "${binfile}" \
executable {debug additional_flags=-O0}] != "" } {
...
meaning there are no separate compile and link steps, as is required for
fission [1].
gdb/record: Support wfi, sfence.vma, sret and mret instructions in risc-v
During testing of bare-metal applications on QEMU for RISC-V, it was discovered
that the instructions wfi, sfence.vma, sret, and mret were not supported. This
patch introduces support for these instructions. Additionally, it wraps
fetch_instruction function in a try-catch block to gracefully handle errors
that may occur when attempting to read invalid address.
Reviewed-By: Guinevere Larsen <guinevere@redhat.com> Approved-By: Andrew Burgess <aburgess@redhat.com>
Tom de Vries [Thu, 28 Aug 2025 09:24:42 +0000 (11:24 +0200)]
[gdb/testsuite] Fix require dwarf2_support check in some test-cases, some more
The Linaro CI reported a regression in test-case
gdb.dwarf2/macro-source-path-clang14-dw4.exp due to recent commit 81e5a23c7b8
("[gdb/testsuite] Fix require dwarf2_support check in some test-cases").
The problem is that the "require dwarf2_support" in its new location doesn't
work because proc dwarf2_support is not defined.
I didn't notice this because I tested all gdb.dwarf2 test-cases together, and
a different test-case had already imported the proc.
H.J. Lu [Wed, 27 Aug 2025 20:17:07 +0000 (13:17 -0700)]
readelf: Update "-D -r" to dump DT_RELR
1. Update dump_relr_relocations to take relr_size, relr_entsize and
relr_offset, instead of a pointer to Elf_Internal_Shdr, as function
arguments.
2. Update process_relocs to call dump_relr_relocations if relocation
type is reltype_relr.
binutils/
PR binutils/33328
* readelf.c (dump_relr_relocations): Replace a pointer to
Elf_Internal_Shdr argument with relr_size, relr_entsize and
relr_offset.
(display_relocations): Update the dump_relr_relocations call.
(process_relocs): Call dump_relr_relocations if relocation type
is reltype_relr.
Simon Marchi [Wed, 6 Aug 2025 19:28:19 +0000 (15:28 -0400)]
gdb/testsuite: get real executable in gdb.gdb/index-file.exp
Similar to a previous patch, if the gdb executable is in fact a libtool
wrapper, we need to get the path to the real executable to load it in
the top-level gdb.
With this change, the test runs on Cygwin, although I do see two
failures:
FAIL: gdb.gdb/index-file.exp: debug_names files are identical
FAIL: gdb.gdb/index-file.exp: debug_str files are identical
Change-Id: Ie06d1ece67e61530e5b664e65b5ef0edccaf6afa Reviewed-By: Keith Seitz <keiths@redhat.com>
Simon Marchi [Wed, 6 Aug 2025 19:28:18 +0000 (15:28 -0400)]
gdb/testsuite: turn thread events off in selftests
When running gdb.gdb/selftest.exp on Cygwin, the test eventually times
out on this command:
(gdb) PASS: gdb.gdb/selftest.exp: printed version as pointer
continue
Continuing.
[New Thread 4804.0x1728]
[New Thread 4804.0x2f24]
[New Thread 4804.0x934]
[New Thread 4804.0x23a8]
[New Thread 4804.0x2cf4]
[New Thread 4804.0x1408]
[New Thread 4804.0x2c90]
[New Thread 4804.0xc58]
[New Thread 4804.0x1d40]
[New Thread 4804.0x1824]
GNU gdb (GDB) 17.0.50.20250530-git
Copyright (C) 2024 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law.
Type "show copying" and "show warranty" for details.
This GDB was configured as "x86_64-pc-cygwin".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<https://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word".
(gdb) [New Thread 4804.0x2c64]
[New Thread 4804.0x23c4]
[New Thread 4804.0x2814]
[Thread 4804.0x1200 exited with code 0]
[Thread 4804.0x293c exited with code 0]
[Thread 4804.0x2c9c exited with code 0]
FAIL: gdb.gdb/selftest.exp: xgdb is at prompt (timeout)
The problem is the new thread notification, and the fact that the test
expects the prompt to be the last thing in the buffer. To avoid the
thread events interfering with the test, disable them, they are not
useful here.
With this patch, gdb.gdb/selftest.exp mostly runs fine on Cygwin, the
only remaining problem appears to be:
(gdb) PASS: gdb.gdb/selftest.exp: send ^C to child process
signal SIGINT
Continuing with signal SIGINT.
PASS: gdb.gdb/selftest.exp: send SIGINT signal to child process, top GDB message
FAIL: gdb.gdb/selftest.exp: send SIGINT signal to child process, bottom GDB message (timeout)
Change-Id: I0b1df0503c1961c042c8de559b4d223c5d3cb95c Reviewed-By: Keith Seitz <keiths@redhat.com>
Simon Marchi [Wed, 27 Aug 2025 19:55:45 +0000 (15:55 -0400)]
gdb/testsuite: use libtool to launch selftests
When building GDB on Cygwin, gdb/gdb.exe is a libtool wrapper (which
happens to be a PE executable). The real executable is at
gdb/.libs/gdb.exe. The "does gdb have debug info test" that
_selftest_setup does is bogus, because it loads the libtool wrapper
(which doesn't have debug info), doesn't see any debug info, and thus
the test is skipped.
The "correct" way to deal with libtool wrappers is to run the shell
command you want to run under `libtool --mode=execute`. That will
replace any path resembling to a libtool wrapper with the real
executable path. But it will also add to the environment the library
paths necessary for this executable to find the libraries it needs.
Therefore, modify the `do_self_tests` proc to:
- run the top-level GDB commands under `libtool --mode=execute`
- pass the path to the inferior GDB on the command-line of the
top-level, so that it gets replaced with the real executable's path
However, the "file" command was previously used to detect the presence
of debug info in the GDB executable. It's not easy to implement this
check when loading the executable directly on the command line. So, add
a separate proc, _selftest_check_executable_debug_info, that spawns a
temporary GDB and does the debug info check through the file command.
This proc uses libtool to obtain the path to the real executable.
When building, we use the bundled libtool.m4 at the top of the tree.
This means that the libtool system package, and therefore the libtool
binary, might not be available. Check for the presence of the libtool
binary first, and only do the conversion if it is found. If it is not
found, the test should still work on platforms that don't require the
conversion.
With this commit, the test runs on Cygwin, even though there are
failures later.
Change-Id: Ie7b712cdc84671a5a017655a7e41687ff23f906c Reviewed-By: Keith Seitz <keiths@redhat.com>
This is done so that the installation is relocatable (the whole ROCm
directory can be copied around) and things still work. For instance,
the rocgdb executable needs to be able to find the libraries it
needs, such as `librocm-dbgapi.so.0`. The relative runpath allows
that.
2. For testing, we run the testsuite against the gdb executable
installed from one of those packages. It is possible to ./configure
the testsuite directory on its own, and then do:
$ make check RUNTESTFLAGS="GDB=/opt/rocm/bin/rocgdb"
3. The selftests (such as gdb.gdb/selftest.exp) copy the GDB under test
to the standard output directory, before trying to debug it.
The problem is that the gdb executable under test that has been copied
can't find the libraries it needs.
With this patch, I propose that we don't copy the gdb executable, but
debug it in place instead. The comment removed in this patch says "in
case this OS doesn't like to edit its own text space", and has been
there since forever in some form. But it's not clear if there is a host
OS (where we intend to run this test) that needs this nowadays. I would
bet that there isn't. If there is in fact a GDB host OS (where we
intend to run this test) that needs it, we can reinstate the copying,
but as an opt-in operation.
Another situation where this change helps is on Windows, where
gdb/gdb.exe is a libtool wrapper (the real executable is at
gdb/.libs/gdb.exe). Copying gdb/gdb.exe doesn't accomplish anything
useful. The next patch does further changes to account for the libtool
wrapper case.
I tested on Linux and Cygwin, more testing would be welcome.
Change-Id: Id4148517d4fc4ecdd49f099c12003e3d16c6a93d Reviewed-By: Keith Seitz <keiths@redhat.com>
Tom Tromey [Wed, 27 Aug 2025 19:29:22 +0000 (13:29 -0600)]
Fix formatting of gdbarch_components.py
pre-commit pointed out that gdbarch_components.py had a minor
formatting issue, according to the official version of 'black'. This
patch corrects the oversight.
Alan Modra [Wed, 27 Aug 2025 08:06:57 +0000 (17:36 +0930)]
objcopy "strip without global symbol" test
This binutils test fails with -fsanitize. NOSANITIZE_CFLAGS isn't
available in the binutils testsuite, and importing it over from ld
requires a huge amount of tcl code to be moved. So I chose to simply
add -fno-sanitize=all if -fsanitize= is seem in CFLAGS.
* testsuite/binutils-all/objcopy.exp
(objcopy_test_without_global_symbol): Add -fno-sanitize=all to
flags if -fsanitize= is found in CFLAGS_FOR_TARGET. Tidy use
of objfile.
* testsuite/binutils-all/tek2.obj: Change to a 3 byte data file
that triggers tekhex error fixed by commit bf0f85df1254.
* testsuite/binutils-all/ar.exp: Adjust to suit.
* testsuite/binutils-all/objcopy.exp (objcopy_tek2bin): New proc.
Alan Modra [Tue, 26 Aug 2025 09:49:44 +0000 (19:19 +0930)]
objcopy "Unable to recognise the format of the input file"
This bogus error comes up when trying something like
objcopy -O binary .../binutils/testsuite/binutils-all/tek2.obj xxx
This is an annoying message, as HJ said in
https://sourceware.org/pipermail/binutils/2002-August/021354.html
and removed it for some cases, eg. I can make it go away by specifying
-I tekhex. The message is also untrue, as objcopy does in fact know
the format of the input file.
I think the message should be limited to ELF input files that are
being handled by the elf64-little, elf64-big, elf32-little or
elf32-big targets, due to libbfd being compiled with limited target
support. I'm also changing the message a litle.
* objcopy.c (copy_object): Change "Unable to recognise format"
message to "Unable to recognise architecture" and only report
this error for ELF objects lacking their proper target support.
* testsuite/binutils-all/x86-64/x86-64.exp: Update to suit.
After commit 5e83077d552e we no longer choose a "plugin" target in
objcopy so ibfd->target_defaults can again be used to test whether the
user supplied a target.
PR 33230
* objcopy.c (copy_file): Revert change adding a target_defaulted
variable and passing down to..
(copy_archive, copy_object): ..here. Remove target_defaulted
parameter. Use ibfd->target_defaulted.
gdb: allow gdb.Color to work correctly with pagination
Which added gdb.python/py-color-pagination.exp. Bug PR gdb/33321 was
then created as the test was failing on some hosts. Turns out, this
is same expect bug.
The fix presented here is the same as for e579b537353cd91cb8, avoid
using optional regexp substrings at the start of a regexp, and instead
use two separate regexp patterns. With this change in place, the test
now passes on all hosts.
There's no change in what is being tested after this commit.
Tom de Vries [Wed, 27 Aug 2025 08:49:19 +0000 (10:49 +0200)]
[gdb/testsuite] Fix gdb.server/non-existing-program.exp on msys2-ucrt64
On msys2-ucrt64, with test-case gdb.server/non-existing-program.exp I get:
...
(gdb) quit^M
gdb_caching_proc allow_xml_test caused gdb_exit to be called
gdb_caching_proc allow_xml_test marked as called
gdb_caching_proc get_mount_point_map marked as called
builtin_spawn gdbserver stdio non-existing-program^M
Error creating process "non-existing-program " (error 2): \
The system cannot find the file specified.^M^M
Exiting^M^M
FAIL: gdb.server/non-existing-program.exp: gdbserver exits cleanly
...
This happens because this regexp fails to match:
...
# This is what we get on Windows.
-re "Error creating process\r\n\r\nExiting\r\n" {
...
projects / thirdparty / binutils-gdb.git / log
