This tidies SEC_RELOC handling in bfd, in the process fixing a bug
with objcopy when renaming sections.
bfd/
* reloc.c (_bfd_generic_set_reloc): Set/clear SEC_RELOC depending
on reloc count.
* elf64-sparc.c (elf64_sparc_set_reloc): Likewise.
binutils/
* objcopy.c (copy_relocations_in_section): Remove now unnecessary
clearing of SEC_RELOC.
* testsuite/binutils-all/rename-section-01.d: New test.
* testsuite/binutils-all/objcopy.exp: Run it.
gas/
* write.c (size_seg): Remove unneccesary twiddle of SEC_RELOC.
(write_relocs): Likewise. Always call bfd_set_reloc.
Commit 02d04eac "Use strwinerror in gdb/windows-nat.c" also moves
strwinerror() under the USE_WIN32API conditional, which is not defined
for Cygwin (and looks like it shouldn't be, as appears to imply
non-POSIX and MiNGW and WinSock...)
Also enable the declaration and definition of strwinerror() when
__CYGWIN__ is defined.
Commit d08bae3d ("Implement target async for Windows") unconditionally
includes winsock2.h. We don't want to do that on Cygwin, since
including both winsock2.h and sys/select.h causes incompatible
redefinition problems.
Since that include is apparently unneeded, just drop it.
Fixes: d08bae3d
If the counter for LOOP instruction is provided by a register with
value zero, then the instruction must cause a PC jump directly to the
loop end. But in that particular case simulator must not initialize
its internal loop variables, because loop body will not be executed.
Instead, simulator must obtain the loop's end address directly from
the LOOP instruction.
Signed-off-by: Dimitar Dimitrov <dimitar@dinux.eu>
On a testcase like
pla 8,foo@pcrel
disassembled with -Mpower10 results in
0: 00 00 10 06 pla r8,0 # 0
4: 00 00 00 39
0: R_PPC64_PCREL34 foo
but with -Mpower10 -Mraw
0: 00 00 10 06 .long 0x6100000
0: R_PPC64_PCREL34 foo
4: 00 00 00 39 addi r8,0,0
The instruction is unrecognised due to the hack we have in
extract_pcrel0 in order to disassemble paddi with RA0=0 and R=1 as
pla. I could have just added "&& !(dialect & PPC_OPCODE_RAW)" to the
condition in extract_pcrel0 under which *invalid is set, but went for
this larger patch that reorders the extended insn pla to the more
usual place before its underlying machine insn. (la is after addi
because we never disassemble to la.)
gas/
* testsuite/gas/ppc/raw.d,
* testsuite/gas/ppc/raw.s: Add pla.
opcodes/
* ppc-opc.c (extract_pcrel1): Rename from extract_pcrel0 and
invert *invalid logic.
(PCREL1): Rename from PCREL0.
(prefix_opcodes): Sort pla before paddi, adjusting R operand
for pla, paddi and psubi.
The configure check for ELF support in BFD uses the AC_TRY_LINK. If
libbfd's dependencies change, this macro will need to be updated
manually with explicit additions to LDFLAGS and LIBS.
This patch updates the check to use libtool instead.
ChangeLog:
* libctf/configure.ac: Use libtool instead.
* libctf/configure: Regenerated.
Commit 0be837be9f ("gdb: make "start" breakpoint inferior-specific")
regresses gdb.ada/start.exp:
(gdb) start
Error in expression, near `1'.
(gdb) UNTESTED: gdb.ada/start.exp: start failed to land inside the right procedure
This is because in Ada, the equality operator is =, not ==.
I checked the other languages supported by GDB, these other languages
use = for equality:
- Pascal: tests like gdb.pascal/hello.exp are affected too
- Modula-2: I tried building a Modula-2 hello world using gm2, but it
seems like the generated DWARF doesn't specify the Modula-2 language
in the CUs, it's C++ and C, so the selected language isn't
"modula-2". But if I manually do "set language modula-2" on a dummy
program and then "start", I get the same error.
Other languages all use ==.
So, a short term fix would be to use = or == in the expression, based on
the current language. If this was meant to be permanent, I would
suggest adding something like an "equality_operator" method to
language_defn, that returns the right equality operator for the
language. But the goal is to replace all this with proper
inferior-specific breakpoints, so I hope all this is temporary.
Approved-By: Tom de Vries <tdevries@suse.de>
Change-Id: Id4d38e14a80e6bbbb1ad2b2277f974dd55192969
We're currently running into a timeout at:
...
(gdb) start ^M
Error in expression, near `1'.^M
(gdb) UNTESTED: gdb.ada/start.exp: start failed to land inside the right \
procedure
...
due to the fact that gdb_start_cmd doesn't handle a prompt as reaction to
the start command.
Fix this by handling the prompt. Reduces execution time of the test-case from
1m1s to 1s.
Tested on x86_64-linux.
With gdb 12.1, on powerpc64le I ran into ERRORs related to has_hw_wp_support
usage, which was already fixed on trunk by commits:
- 13f7237241 ("gdb/testsuite: fix gdb.base/break-idempotent.exp on ppc"), and
- 01a32ee0b8 ("PowerPC, fix gdb.base/watchpoint.exp on Power 9")
While looking into these ERRORs and the commits that fix them, it occurred to
me that while the commits fix the root cause, the failure mode is not great.
The test-cases expect a running instance of gdb upon return, which is not
there, so there's an long stream of ERRORs generated as a result.
Fix this at the start of has_hw_wp_support, by (instead of accomodating a
running gdb instance by calling gdb_exit), checking whether it's called
without a running gdb instance, and erroring out otherwise. This way, there's
just one error.
I also noticed that in case we do an early exit due to !runto_main, we don't
clean up, so copy the missing cleanups (gdb_exit and $obj file deletion) from
the regular exit.
Tested on x86_64-linux, using has_hw_wp_support for x86_64 in
skip_hw_watchpoint_tests.
The python code maintains a list of threads for each inferior. This
list is implemented as a linked list. When the number of threads grows
high, this implementation can begin to be a performance bottleneck as
finding a particular thread_object in the list has a complexity of O(N).
We see this in ROCgdb[1], a downstream port of GDB for AMDGUP. On
AMDGPU devices, the number of threads can get significantly higher than
on usual GDB workloads.
In some situations, we can reach the end of the inferior process with
GDB still having a substantial list of known threads. While running
target_mourn_inferior, we end up in inferior::clear_thread_list which
iterates over all remaining threads and marks each thread exited. This
fires the gdb::observers::thread_exit observer and eventually
py-inferior.c:set_thread_exited gets called. This function searches in
the linked list with poor performances.
This patch proposes to change the linked list that keeps the per
inferior_object list of thread_objects into a std::unordered_map. This
allows to have the search operation complexity be O(1) on average
instead of O(N).
With this patch, we can complete clear_thread_list in about 2.5 seconds
compared to 10 minutes without it.
Except for the performance change, no user visible change is expected.
Regression tested on Ubuntu-22.04 x86_64.
[1] https://github.com/ROCm-Developer-Tools/ROCgdb
PR gdb/29272
Investigating PR29272, it was mentioned a particular test used to work on
GDB 10, but it started failing with GDB 11 onwards. I tracked it down to
some displaced stepping improvements on commit
187b041e25.
In particular, one of the corner cases using copy_insn_closure_by_addr got
silently broken. It is hard to spot because it doesn't have any good tests
for it, and the situation is quite specific to the Arm target.
Essentially, the change from the displaced stepping improvements made it so
we could still invoke copy_insn_closure_by_addr correctly to return the
pointer to a copy_insn_closure, but it always returned nullptr due to
the order of the statements in displaced_step_buffer::prepare.
The way it is now, we first write the address of the displaced step buffer
to PC and then save the copy_insn_closure pointer.
The problem is that writing to PC for the Arm target requires figuring
out if the new PC is thumb mode or not.
With no copy_insn_closure data, the logic to determine the thumb mode
during displaced stepping doesn't work, and gives random results that
are difficult to track (SIGILL, SIGSEGV etc).
Fix this by reordering the PC write in displaced_step_buffer::prepare
and, for safety, add an assertion to
displaced_step_buffer::copy_insn_closure_by_addr so GDB stops right
when it sees this invalid situation. If this gets broken again in the
future, it will be easier to spot.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29272
Approved-By: Simon Marchi <simon.marchi@efficios.com>
When running the test with the latest Intel compiler:
Running gdb/gdb/testsuite/gdb.btrace/rn-dl-bind.exp ...
gdb compile failed, icpx: warning: treating 'c' input as 'c++' when
in C++ mode, this behavior is deprecated [-Wdeprecated]
The test doesn't seem to test something specifically for C++,
so I removed the C++ compilation option. Alternatively we could rename
rn-dl-bind.exp.c to rn-dl-bind.exp.cc.
Signed-off-by: Felix Willgerodt <felix.willgerodt@intel.com>
The test gdb.cp/call-method-register.exp assumes that the class will be
placed on a register. However, this keyword has been deprecated since
C++11, and Clang, for instance, does not feel the need to follow it.
Since this test is not usable without this working, this commit marks
this test as untested.
Approved-by: Tom Tromey <tom@tromey.com>
gdb.cp/temargs.exp last 2 tests always setup an XFAILs, despite checking
for old gcc versions. However, Clang does not fail in this test,
turning into XPASSes and slighty annoying when comparing between
compilers. To change this, make the xfails only happen if we using gcc.
Approved-by: Tom Tromey <tom@tromey.com>
Since Clang chooses to not add any debug information for base types,
expecting it to be included with libraries' informations, gdb.cp/typeid.exp
will always fail if the program hasn't started. This commit fixes that by
making it so when using Clang, the base type variables aren't tested.
Approved-by: Tom Tromey <tom@tromey.com>
When Clang compiles anonymous structures, it does not add linkage names in
their dwarf representations. This is compounded by Clang not adding linkage
names to subprograms of those anonymous structs (for instance, the
constructor). With these 2 things together, GDB is unable to refer to
any of them, so there is no way to pass any of the tests of
gdb.cp/anon-struct.exp
Since this isn't a bug on Clang or GDB according to the DWARF
specifications as DW_AT_name is optional for all DIEs, the test was marked
as untested.
Since I was already touching the file, I also added a comment at the top
of the file explaining what it is testing for.
Approved-by: Tom Tromey <tom@tromey.com>
when running gdb.cp/m-static.exp using Clang, we get the following
failures:
print test1.~gnu_obj_1^M
$6 = {void (gnu_obj_1 * const)} 0x555555555470 <gnu_obj_1::~gnu_obj_1()>^M
(gdb) FAIL: gdb.cp/m-static.exp: simple object instance, print destructor
ptype test1.~gnu_obj_1^M
type = void (gnu_obj_1 * const)^M
(gdb) FAIL: gdb.cp/m-static.exp: simple object instance, ptype destructor
print test1.'~gnu_obj_1'^M
$7 = {void (gnu_obj_1 * const)} 0x555555555470 <gnu_obj_1::~gnu_obj_1()>^M
(gdb) FAIL: gdb.cp/m-static.exp: simple object instance, print quoted destructor
This is because the test is expecting an extra integer parameter on the
destructor. Looking at the debuginfo, it seems that there is nothing
actually wrong with this output, so these tests were changed to test
multiple possible regexps.
Approved-by: Tom Tromey <tom@tromey.com>
When running gdb.cp/derivation.exp using Clang, we get an unexpected
failure when printing the type of a class with an internal typedef. This
happens because Clang doesn't add accessibility information for typedefs
inside classes (see https://github.com/llvm/llvm-project/issues/57608
for more info). To help with Clang testing, an XFAIL was added to this
test.
Approved-by: Tom Tromey <tom@tromey.com>
When compiling virtual classes's destructors, two versions are compiled,
one with a single parameter (this) and the other with 2 parameters (this
and vtt).
GCC's compilation makes it so either the version with 1
parameter or the one with 2 parameters is called, depending on whether
the destructor is being called by the class itself or by an inherited
class. On the test gdb.cp/mb-ctor.exp, this means that the breakpoint
set at the destructor will be hit 4 times.
Clang, on the other hand, makes the single-parameter version call the 2
parameter version, probably in an attempt to reduce the size of the
resulting executable. This means that the gdb.cp/mb-ctor.exp will hit 6
breakpoints before finishing, and is the reason why this test was
failing. To make this test stop failing, a compiler check is added and
another "continue" instruction is issued to account for this difference.
Approved-by: Tom Tromey <tom@tromey.com>
When attempting to run the gdb.cp/classes.exp test using Clang++, the
test fails to prepare with -Wnon-c-typedef-for-linkage like the
previously fixed gdb.cp/class2.exp. Upon fixing this, the test shows 5
unexpected failures. One such failures is:
ptype/r class class_with_public_typedef
type = class class_with_public_typedef {
private:
int a;
public:
class_with_public_typedef::INT b;
private:
typedef int INT;
}
(gdb) FAIL: gdb.cp/classes.exp: ptype class class_with_public_typedef // wrong access specifier for typedef: private
While g++ provided the following output:
ptype/r class class_with_public_typedef
type = class class_with_public_typedef {
private:
int a;
public:
class_with_public_typedef::INT b;
typedef int INT;
}
(gdb) PASS: gdb.cp/classes.exp: ptype class class_with_public_typedef
This error happens because Clang does not add DW_AT_accessibility to
typedefs inside classes, and without this information GDB defaults to
assuming the typedef is private. Since there is nothing that GDB can do
about this, these tests have been set as xfails, and Clang bug 57608 has
been filed.
Bug: https://github.com/llvm/llvm-project/issues/57608
Approved-by: Tom Tromey <tom@tromey.com>
When attempting to test gdb.cp/class2.exp using Clang, it fails to
prepare with the following error:
Executing on host: clang++ -fdiagnostics-color=never -Wno-unknown-warning-option -c -g -o /home/blarsen/Documents/fsf_build/gdb/testsuite/outputs/gdb.cp/class2/class20.o /home/blarsen/Documents/fsf_build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.cp/class2.cc (timeout = 300)
builtin_spawn -ignore SIGHUP clang++ -fdiagnostics-color=never -Wno-unknown-warning-option -c -g -o /home/blarsen/Documents/fsf_build/gdb/testsuite/outputs/gdb.cp/class2/class20.o /home/blarsen/Documents/fsf_build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.cp/class2.cc
/home/blarsen/Documents/fsf_build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.cp/class2.cc:53:14: warning: anonymous non-C-compatible type given name for linkage purposes by typedef declaration; add a tag name here [-Wnon-c-typedef-for-linkage]
typedef class {
^
Dbase
/home/blarsen/Documents/fsf_build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.cp/class2.cc:54:2: note: type is not C-compatible due to this member declaration
public:
^~~~~~~
/home/blarsen/Documents/fsf_build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.cp/class2.cc:58:3: note: type is given name 'Dbase' for linkage purposes by this typedef declaration
} Dbase;
^
1 warning generated.
gdb compile failed, /home/blarsen/Documents/fsf_build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.cp/class2.cc:53:14: warning: anonymous non-C-compatible type given name for linkage purposes by typedef declaration; add a tag name here [-Wnon-c-typedef-for-linkage]
typedef class {
^
Dbase
/home/blarsen/Documents/fsf_build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.cp/class2.cc:54:2: note: type is not C-compatible due to this member declaration
public:
^~~~~~~
/home/blarsen/Documents/fsf_build/gdb/testsuite/../../../binutils-gdb/gdb/testsuite/gdb.cp/class2.cc:58:3: note: type is given name 'Dbase' for linkage purposes by this typedef declaration
} Dbase;
^
1 warning generated.
UNTESTED: gdb.cp/class2.exp: failed to prepare
This can be silenced by adding -Wno-non-c-typedef-for-linkage for Clang
11 or later. The test shows no failures with this change.
Approved-by: Tom Tromey <tom@tromey.com>
While .linefile is generally intended for gas internal use only, its use
in a source file would better not result in an internal error. Give use
of it outside of any macro(-like) construct the meaning of restoring the
original (physical) input file name.
This patch provides a new function to sanity check section sizes.
It's mostly extracted from what we had in bfd_get_full_section_contents
but also handles compressed debug sections.
Improvements are:
- section file offset is taken into account,
- added checks that a compressed section can be read from file.
The function is then used when handling multiple .debug_* sections
that need to be read into a single buffer, to sanity check sizes
before allocating the buffer.
PR 26946, PR 28834
* Makefile.am (LIBBFD_H_FILES): Add section.c.
* compress.c (bfd_get_full_section_contents): Move section size
sanity checks..
* section.c (_bfd_section_size_insane): ..to here. New function.
* dwarf2.c (read_section): Use _bfd_section_size_insane.
(_bfd_dwarf2_slurp_debug_info): Likewise.
* Makefile.in: Regenerate.
* libbfd.h: Regenerate.
This option compresses output debug sections with zstd and sets ch_type
to ELFCOMPRESS_ZSTD. Latest gdb and lldb support ELFCOMPRESS_ZSTD.
There will be an error if zstd is not enabled at configure time.
error: --compress-debug-sections=zstd: gold is not built with zstd support
The parser for boolean rules fails to skip over the , separator in
the options which makes it hang forever. No dc files in the tree
use boolean rules atm which is why no one noticed.
To make it clear this is an input to the igen tool, rename it with an
igen extension. This matches the other files in the ppc dir (altivec
& e500 igen files), and the other igen ports (mips, mn10300, v850).
(%dx) isn't a valid memory address in any modes. It is used as a special
memory operand for input/output port address in AT&T syntax and should
only be used with input/output instructions. Update i386_att_operand to
set i.input_output_operand to true for (%dx) and issue an error if (%dx)
is used with non-input/output instructions.
PR gas/29751
* config/tc-i386.c (_i386_insn): Add input_output_operand.
(md_assemble): Issue an error if input/output memory operand is
used with non-input/output instructions.
(i386_att_operand): Set i.input_output_operand to true for
(%dx).
* testsuite/gas/i386/inval.l: Updated.
* testsuite/gas/i386/x86-64-inval.l: Likewise.
* testsuite/gas/i386/inval.s: Add tests for invalid (%dx) usage.
* testsuite/gas/i386/x86-64-inval.s: Likewise.
I saw this failure on a CI:
(gdb) add-inferior
[New inferior 2]
Added inferior 2
(gdb) PASS: gdb.threads/vfork-multi-inferior.exp: method=non-stop: add-inferior
inferior 2
[Switching to inferior 2 [<null>] (<noexec>)]
(gdb) PASS: gdb.threads/vfork-multi-inferior.exp: method=non-stop: inferior 2
kill
The program is not being run.
(gdb) file /home/jenkins/workspace/binutils-gdb_master_linuxbuild/platform/jammy-amd64/target_board/unix/tmp/tmp.GYATAXR8Ku/gdb/testsuite/outputs/gdb.threads/vfork-multi-inferior/vfork-multi-inferior-sleep
Reading symbols from /home/jenkins/workspace/binutils-gdb_master_linuxbuild/platform/jammy-amd64/target_board/unix/tmp/tmp.GYATAXR8Ku/gdb/testsuite/outputs/gdb.threads/vfork-multi-inferior/vfork-multi-inferior-sleep...
(gdb) run &
Starting program: /home/jenkins/workspace/binutils-gdb_master_linuxbuild/platform/jammy-amd64/target_board/unix/tmp/tmp.GYATAXR8Ku/gdb/testsuite/outputs/gdb.threads/vfork-multi-inferior/vfork-multi-inferior-sleep
(gdb) PASS: gdb.threads/vfork-multi-inferior.exp: method=non-stop: run inferior 2
inferior 1
[Switching to inferior 1 [<null>] (<noexec>)]
(gdb) PASS: gdb.threads/vfork-multi-inferior.exp: method=non-stop: inferior 1
kill
The program is not being run.
(gdb) file /home/jenkins/workspace/binutils-gdb_master_linuxbuild/platform/jammy-amd64/target_board/unix/tmp/tmp.GYATAXR8Ku/gdb/testsuite/outputs/gdb.threads/vfork-multi-inferior/vfork-multi-inferior
Reading symbols from /home/jenkins/workspace/binutils-gdb_master_linuxbuild/platform/jammy-amd64/target_board/unix/tmp/tmp.GYATAXR8Ku/gdb/testsuite/outputs/gdb.threads/vfork-multi-inferior/vfork-multi-inferior...
(gdb) break should_break_here
Breakpoint 1 at 0x11b1: file /home/jenkins/workspace/binutils-gdb_master_linuxbuild/platform/jammy-amd64/target_board/unix/src/binutils-gdb/gdb/testsuite/gdb.threads/vfork-multi-inferior.c, line 25.
(gdb) PASS: gdb.threads/vfork-multi-inferior.exp: method=non-stop: break should_break_here
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
start
Temporary breakpoint 2 at 0x11c0: -qualified main. (2 locations)
Starting program: /home/jenkins/workspace/binutils-gdb_master_linuxbuild/platform/jammy-amd64/target_board/unix/tmp/tmp.GYATAXR8Ku/gdb/testsuite/outputs/gdb.threads/vfork-multi-inferior/vfork-multi-inferior
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Thread 2.1 "vfork-multi-inf" hit Temporary breakpoint 2, main () at /home/jenkins/workspace/binutils-gdb_master_linuxbuild/platform/jammy-amd64/target_board/unix/src/binutils-gdb/gdb/testsuite/gdb.threads/vfork-multi-inferior-sleep.c:23
23 sleep (30);
(gdb) FAIL: gdb.threads/vfork-multi-inferior.exp: method=non-stop: start inferior 1
What happens is:
1. We start inferior 2 with "run&", it runs very slowly, takes time to
get to main
2. We switch to inferior 1, and run "start"
3. The temporary breakpoint inserted by "start" applies to all inferiors
4. Inferior 2 hits that breakpoint and GDB reports that hit
To avoid this, breakpoints inserted by "start" should be
inferior-specific. However, we don't have a nice way to make
inferior-specific breakpoints yet. It's possible to make
pspace-specific breakpoints (for example how the internal_breakpoint
constructor does) by creating a symtab_and_line manually. However,
inferiors can share program spaces (usually on particular embedded
targets), so we could have a situation where two inferiors run the same
code in the same program space. In that case, it would just not be
possible to insert a breakpoint in one inferior but not the other.
A simple solution that should work all the time is to add a condition to
the breakpoint inserted by "start", to check the inferior reporting the
hit is the expected one. This is what this patch implements.
Add a test that does:
- start in background inferior 1 that sleeps before reaching its main
function (using a sleep in a global C++ object's constructor)
- start inferior 2 with the "start" command, which also sleeps before
reaching its main function
- validate that we hit the breakpoint in inferior 2
Without the fix, we hit the breakpoint in inferior 1 pretty much all the
time. There could be some unfortunate scheduling causing the test not
to catch the bug, for instance if the scheduler decides not to schedule
inferior 1 for a long time, but it would be really rare. If the bug is
re-introduced, the test will catch it much more often than not, so it
will be noticed.
Reviewed-By: Bruno Larsen <blarsen@redhat.com>
Approved-By: Pedro Alves <pedro@palves.net>
Change-Id: Ib0148498a476bfa634ed62353c95f163623c686a
Commit 041de3d73a changed the output format of all error messages when
GDB couldn't determine a compatible overload for a given function, but
it was only supposed to change if the failure happened due to incomplete
types. This commit removes the stray . that was added
If the download size is known, a progress bar is displayed along with
the percentage of completion and the total download size.
Downloading separate debug info for /lib/libxyz.so
[############ ] 25% (10.01 M)
If the download size is not known, a progress indicator is displayed
with a ticker ("###") that moves across the screen at a rate of 1 tick
every 0.5 seconds.
Downloading separate debug info for /lib/libxyz.so
[ ### ]
If the output stream is not a tty, batch mode is enabled, the screen is
too narrow or width has been set to 'unlimited', then only a static
description of the download is printed. No bar or ticker is displayed.
Downloading separate debug info for /lib/libxyz.so...
In any case, if the size of the download is known at the time the
description is printed then it will be included in the description.
Downloading 10.01 MB separate debug info for /lib/libxyz.so...
I noticed this problem while preparing the initial submission for the
ROCm GDB port. One particularity of this patch set is that it does not
support unwinding frames, that requires support of some DWARF extensions
that will come later. It was still possible to run to a breakpoint and
print frame #0, though.
When rebasing on top of the frame_info_ptr work, GDB started tripping on
a prepare_reinflate call, making it not possible anymore to event print
the frame when stopping on a breakpoint. One thing to know about frame
0 is that its id is lazily computed when something requests it through
get_frame_id. See:
23912acd40/gdb/frame.c (L2070-2080)
So, up to that prepare_reinflate call, frame 0's id was not computed,
and prepare_reinflate, calling get_frame_id, forces it to be computed.
Computing the frame id generally requires unwinding the previous frame,
which with my ROCm GDB patch fails. An exception is thrown and the
printing of the frame is simply abandonned.
Regardless of this ROCm GDB problem (which is admittedly temporary, it
will be possible to unwind with subsequent patches), we want to avoid
prepare_reinflate to force the computing of the frame id, for the same
reasons we lazily compute it in the first place.
In addition, frame 0's id is subject to change across a frame cache
reset. This is why save_selected_frame and restore_selected_frame have
special handling for frame 0:
23912acd40/gdb/frame.c (L1841-1863)
For this last reason, we also need to handle frame 0 specially in
prepare_reinflate / reinflate. Because the frame id of frame 0 can
change across a frame cache reset, we must not rely on the frame id from
that frame to reinflate it. We should instead just re-fetch the current
frame at that point.
This patch adds a frame_info_ptr::m_cached_level field, set in
frame_info_ptr::prepare_reinflate, so we can tell if a frame is frame 0.
There are cases where a frame_info_ptr object wraps a sentinel frame,
for which frame_relative_level returns -1, so I have chosen the value -2
to represent "invalid frame level", for when the frame_info_ptr object
is empty.
In frame_info_ptr::prepare_reinflate, only cache the frame id if the
frame level is not 0. It's fine to cache the frame id for the sentinel
frame, it will be properly handled by frame_find_by_id later.
In frame_info_ptr::reinflate, if the frame level is 0, call
get_current_frame to get the target's current frame. Otherwise, use
frame_find_by_id just as before.
This patch should not have user-visible changes with upstream GDB. But
it will avoid forcing the computation of frame 0's when calling
prepare_reinflate. And, well, it fixes the upcoming ROCm GDB patch
series.
Change-Id: I176ed7ee9317ddbb190acee8366e087e08e4d266
Reviewed-By: Bruno Larsen <blarsen@redhat.com>
print_frame_info calls frame_info_ptr::reinflate, but not
frame_info_ptr::prepare_reinflate, add the call to prepare_reinflate.
It works right now, because all callers of print_frame_info that could
possibly lead to the pretty printers being called, and the frame_info
objects being invalidated, do call prepare_reinflate themselves. And
since the cached frame id is copied when passing a frame_info_ptr by
value, print_frame_info does have a cached frame id on entry. So
technically, this change isn't needed. But I don't think it's good for
a function to rely on its callers to have called prepare_reinflate, if
it intends to call reinflate.
Change-Id: Ie332b2d5479aef46f83fdc1120c7c83f4e84d1b0
Reviewed-By: Bruno Larsen <blarsen@redhat.com>
The assertion
gdb_assert (m_cached_id != null_frame_id);
is always true, as comparing equal to null_frame_id is always false
(it's the first case in frame_id::operator==, not sure why it's not this
way, but that's what it is).
Replace the comparison with a call to frame_id_p.
Approved-By: Tom Tromey <tom@tromey.com>
Change-Id: I93986e6a85ac56353690792552e5b3b4cedec7fb
With the following patch applied (gdb: use frame_id_p instead of
comparing to null_frame_id in frame_info_ptr::reinflate), I would get:
$ ./gdb -q -nx --data-directory=data-directory testsuite/outputs/gdb.base/bt-selected-frame/bt-selected-frame -ex "b breakpt" -ex r -ex "bt full"
Reading symbols from testsuite/outputs/gdb.base/bt-selected-frame/bt-selected-frame...
Breakpoint 1 at 0x1131: file /home/smarchi/src/binutils-gdb/gdb/testsuite/gdb.base/bt-selected-frame.c, line 22.
Starting program: /home/smarchi/build/binutils-gdb/gdb/testsuite/outputs/gdb.base/bt-selected-frame/bt-selected-frame
[Thread debugging using libthread_db enabled]
Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
Breakpoint 1, breakpt () at /home/smarchi/src/binutils-gdb/gdb/testsuite/gdb.base/bt-selected-frame.c:22
22 }
#0 breakpt () at /home/smarchi/src/binutils-gdb/gdb/testsuite/gdb.base/bt-selected-frame.c:22
No locals.
/home/smarchi/src/binutils-gdb/gdb/frame-info.c:42: internal-error: reinflate: Assertion `frame_id_p (m_cached_id)' failed.
This is because the code in backtrace_command_1 to manually reinflate
`fi` steps overs frame_info_ptr's toes.
When calling
fi.prepare_reinflate ();
`fi` gets properly filled with the cached frame id. But when this
happens:
fi = frame_find_by_id (frame_id);
`fi` gets replaced by a brand new frame_info_ptr that doesn't have a
cached frame id. Then this is called without a cached frame id:
fi.reinflate ();
That doesn't cause any problem currently, since
- the gdb_assert in the reinflate method doesn't actually do anything
(the following patch fixes that)
- `fi.m_ptr` will always be non-nullptr, since we just got it from
frame_find_by_id, so reinflate will not do anything, it won't try to
use m_cached_id
Fix that by removing the code to manually re-fetch the frame. That
should be taken care of by frame_info_ptr::reinflate.
Note that the old code checked if we successfully re-inflated the frame
or not, and if not it did emit a warning. The equivalent in
frame_info_ptr::reinflate asserts that the frame has been successfully
re-inflated. It's not clear if / when this can happen, but if it can
happen, we'll need to find a solution to this problem globally
(everywhere a frame_info_ptr can be re-inflated), not just here. So I
propose to leave it like this, until it does become a problem.
Reviewed-By: Bruno Larsen <blarsen@redhat.com>
Change-Id: I07b783d94e2853e0a2d058fe7deaf04eddf24835
