We already have one overload of the startswith function that takes a
std::string_view for both arguments. A later patch in this series is
going to be improved by having an overload that takes one argument as
a std::string_view and the other argument as a plain 'char *'.
This commit adds the new overload, but doesn't make use of it (yet).
There should be no user visible changes after this commit.
I spotted that the gdb.base/sysroot-debug-lookup.exp test that I added
recently actually had a KPASS when run with the
native-extended-gdbserver board. This was an oversight when adding
the test.
The failures in this test, when using the 'unix' board, are logged as
bug PR gdb/31804. The problem appears to be caused by the use of the
child_path function in find_separate_debug_file.
What happens on the 'unix' board is that the file is specified to GDB
with a target: prefix, however GDB spots that the target filesystem is
local to GDB and so opens the file without a target: prefix. When we
call into find_separate_debug_file the DIR and CANON_DIR arguments,
which are computed from the objfile_name() no longer have a target:
prefix.
However, in this test if the file was opened with a target: prefix,
then the sysroot also has a target: prefix. When child_path is called
it looks for a common prefix between CANON_DIR (from the objfile_name)
and the sysroot. However, the sysroot still has the target: prefix,
which means the child_path() call fails and returns nullptr.
What happens in the native-extended-gdbserver case is that GDB doesn't
see the target filesystem as local. Now the filename retains the
target: prefix, which means that in the child_path() call both the
sysroot and the CANON_DIR have a target: prefix, and so the
child_path() call succeeds. This allows GDB to progress, try some
additional paths, and then find the debug information.
So, this commit changes gdb.base/sysroot-debug-lookup.exp to expect
the test to succeed when using the native-extended-gdbserver protocol.
This leaves one KFAIL when using the native-extended-gdbserver board,
we find the debug information but (apparently) find it in the wrong
file. What's happening is that when GDB builds the filename for the
debug information we end up with a '//' string as a directory
separator, the test regexp only expects a single separator.
Instead of just fixing the test regexp, I've updated the path_join
function in gdbsupport/pathstuff.{cc,h} to allow for absolute paths to
appear in the argument list after the first argument. This means it's
now possible to do this:
auto result = path_join ("/a/b/c", "/d/e/f");
gdb_assert (result == "/a/b/c/d/e/f");
Additionally I've changed path_join so that it avoids adding
unnecessary directory separators. In the above case when the two
paths were joined GDB only added a single separator between 'c' and
'd'. But additionally, if we did this:
auto result = path_join ("/a/b/c/", "/d/e/f");
gdb_assert (result == "/a/b/c/d/e/f");
We'd still only get a single separator.
With these changes to path_join I can now make use of this function in
find_separate_debug_file. With this done I now have no KFAIL when
using the native-extended-gdbserver board.
After this commit we still have 2 KFAIL when not using the
native-gdbserver and unix boards, these will be addressed in the next
commit.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31804
Reviewed-By: Keith Seitz <keiths@redhat.com>
By default GDB will be printing the hex payload of the ptwrite package as
auxiliary information. To customize this, the user can register a ptwrite
filter function in python, that takes the payload and the PC as arguments and
returns a string which will be printed instead. Registering the filter
function is done using a factory pattern to make per-thread filtering easier.
Approved-By: Markus Metzger <markus.t.metzger@intel.com>
This enables gdb and gdbserver to communicate about ptwrite support. If
ptwrite support would be enabled unconditionally, GDBs with older libipt
versions would break.
Approved-By: Markus Metzger <markus.t.metzger@intel.com>
Reviewed-By: Eli Zaretskii <eliz@gnu.org>
This might have been useful during the C -> C++ conversion (not sure),
but it doesn't appear useful today. I don't see when enum-flags.h would
be used in a C context.
Change-Id: I6c7ed655757248a62a1bf6615995f42e8aa2b4bd
REALTIME_LO was only possibly previously defined in config/nm-nto.h,
which is now removed. So we can remove the #ifndef protecting against a
redefinition of REALTIME_LO in gdbsupport/signals.cc.
Change-Id: I021b9518ceaa6223bd480ff1e07e9a978b0b241e
Approved-by: Kevin Buettner <kevinb@redhat.com>
Now that all known uses of VLAs within GDB are removed, remove the
`-Wno-vla-cxx-extension` (which was used to silence clang warnings) and
add `-Wvla`, such that any use of a VLA will trigger a warning.
Change-Id: I69a8d7f93f973743165b0ba46f9c2ea8adb89025
Reviewed-By: Keith Seitz <keiths@redhat.com>
C++ 11 has a built-in attribute for this, no need to use a compat macro.
Change-Id: I90e4220d26e8f3949d91761f8a13cd9c37da3875
Reviewed-by: Lancelot Six <lancelot.six@amd.com>
Like the previous commit, add two overloads of gdb_tilde_expand, one
takes std::string and other takes gdb::unique_xmalloc_ptr<char>. Make
use of these overloads throughout GDB and gdbserver.
There should be no user visible changes after this commit.
Approved-By: Tom Tromey <tom@tromey.com>
Add two overloads of gdb_abspath, one which takes std::string and one
which takes gdb::unique_xmalloc_ptr<char>, then make use of these
overloads throughout GDB and gdbserver.
There should be no user visible changes after this commit.
Approved-By: Tom Tromey <tom@tromey.com>
I think that hashtabs should never be obstack-allocated. In the past
this was convenient sometimes, because any new data structure needed a
corresponding cleanup. However, with the switch to C++, resource
management has become much simpler; for example, a local variable can
simply be of type htab_up rather than hashtab_t, and the problem is
solved.
This patch removes hashtab_obstack_allocate to try to prevent this
anti-pattern from being used again.
Share the definition of I386_LINUX_XSAVE_XCR0_OFFSET between GDB and
gdbserver.
This commit moves the definition into gdbsupport/x86-xstate.h, which
allows the #define to be shared.
There should be no user visible changes after this commit.
Approved-By: Felix Willgerodt <felix.willgerodt@intel.com>
I believe that the get_exec_file function is unnecessary, and the code
can be simplified if we remove it.
Consider for instance when you "run" a program on Linux with native
debugging.
1. run_command_1 obtains the executable file from
`current_program_space->exec_filename ()`
2. it passes it to `run_target->create_inferior()`, which is
`inf_ptrace_target::create_inferior()` in this case, which then
passes it to `fork_inferior()`
3. `fork_inferior()` then has a fallback, where if the passed exec file
is nullptr, it gets its from `get_exec_file()`.
4. `get_exec_file()` returns `current_program_space->exec_filename ()`
- just like the things we started with - or errors out if the
current program space doesn't have a specified executable.
If there's no exec filename passed in step 1, there's not going to be
any in step 4, so it seems pointless to call `get_exec_file()`, we could
just error out when `exec_file` is nullptr. But we can't error out
directly in `fork_inferior()`, since the error is GDB-specific, and that
function is shared with GDBserver.
Speaking of GDBserver, all code paths that lead to `fork_inferior()`
provide a non-nullptr exec file.
Therefore, to simplify things:
- Make `fork_inferior()` assume that the passed exec file is not
nullptr, don't call `get_exec_file()`
- Change some targets (darwin-nat, go32-nat, gnu-nat, inf-ptrace,
nto-procfs, procfs) to error out when the exec file passed to their
create_inferior method is nullptr. Some targets are fine with a
nullptr exec file, so we can't check that in `run_command_1()`.
- Add the `no_executable_specified_error()` function, which re-uses the
error message that `get_exec_file()` had.
- Change some targets (go32-nat, nto-procfs) to not call
`get_exec_file()`, since it's pointless for the same reason as in the
example above, if it returns, it's going the be the same value as the
`exec_file` parameter. Just rely on `exec_file`.
- Remove the final use of `get_exec_file()`, in `load_command()`.
- Remove the `get_exec_file()` implementations in GDB and GDBserver and
remove the shared declaration.
Change-Id: I601c16498e455f7baa1f111a179da2f6c913baa3
Approved-By: Tom Tromey <tom@tromey.com>
Calls of `get_exec_file (0)` are equivalent to just getting the exec
filename from the current program space. I'm looking to remove
`get_exec_file`, so replace these uses with
`current_program_space->exec_filename ()`.
Remove the `err` parameter of `get_exec_wrapper` since all the calls
that remain pass 1, meaning to error out if no executable is specified.
Change-Id: I7729ea4c7f03dbb046211cc5aa3858ab3a551965
Approved-By: Tom Tromey <tom@tromey.com>
Currently, if you configure gdb with explicit --enable-threading, but
then configure detects std::thread does not work, configure silently
disables threading support and continues configuring.
This patch makes that scenario cause a configuration error, like so:
$ /home/pedro/gdb/src/configure --enable-threading && make
...
configure: error: std::thread does not work; disable threading
make[1]: *** [Makefile:11225: configure-gdbsupport] Error 1
make[1]: Leaving directory '/home/pedro/gdb/build-windows-threads'
make: *** [Makefile:1041: all] Error 2
$
Additionally, if you don't explicitly pass --enable-threading, and
std::thread does not work, we will now get a warning (and the build
continues):
$ /home/pedro/gdb/src/configure && make
...
configure: WARNING: std::thread does not work; disabling threading
...
This is similar to how we handle --enable-tui and missing curses. The
code and error/warning messages were borrowed from there.
Change-Id: I73a8b580d1e2a796b23136920c0e181408ae1b22
Approved-By: Tom Tromey <tom@tromey.com>
With a x86_64-pc-mingw32 toolchain there is a build issue
whether or not the --disable-threading option is used.
The problem happens because _WIN32_WINNT is defined to 0x501
before #include <mutex> which makes the compilation abort
due to missing support for __gthread_cond_t in std_mutex.h,
which is conditional on _WIN32_WINNT >= 0x600.
Fix the case when --disable-threading is used, by only
including <mutex> in gdb/complaints.c when STD_CXX_THREAD
is defined.
Additionally make the configure script try to #include <mutex>
to automatically select --disable-threading when the header file
is not able to compile.
Approved-By: Tom Tromey <tom@tromey.com>
In my occasional and continuing campaign against realloc, this patch
changes event-loop.cc to use std::vector to keep track of pollfd
objects. Regression tested on x86-64 Fedora 38.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Approved-By: John Baldwin <jhb@FreeBSD.org>
There is no reason the callers of these functions need to change the
returned string, so change the `char *` return types to `const char *`.
Update a few callers to also use `const char *`.
Change-Id: I94adff574d5e1b326e8cc688cf1817a15b408b96
Approved-By: Tom Tromey <tom@tromey.com>
When building with clang 18, I see:
CXX aarch64-linux-tdep.o
/home/smarchi/src/binutils-gdb/gdb/aarch64-linux-tdep.c:1299:26: error: variable length arrays in C++ are a Clang extension [-Werror,-Wvla-cxx-extension]
1299 | gdb_byte za_zeroed[za_bytes];
| ^~~~~~~~
/home/smarchi/src/binutils-gdb/gdb/aarch64-linux-tdep.c:1299:26: note: read of non-const variable 'za_bytes' is not allowed in a constant expression
/home/smarchi/src/binutils-gdb/gdb/aarch64-linux-tdep.c:1282:10: note: declared here
1282 | size_t za_bytes = std::pow (sve_vl_from_vg (svg), 2);
| ^
Since we are using VLAs right now, that warning doesn't make sense for
us. add `-Wno-vla-cxx-extension` to the list of warning flags we try to
enable. If we ever choose to disallow VLAs, we can remove that flag.
Change-Id: Ie41feafc50c343f6e75333d4f836ce32fbeb6d8c
Now that defs.h, server.h and common-defs.h are included via the
`-include` option, it is no longer necessary for source files to include
them. Remove all the inclusions of these files I could find. Update
the generation scripts where relevant.
Change-Id: Ia026cff269c1b7ae7386dd3619bc9bb6a5332837
Approved-By: Pedro Alves <pedro@palves.net>
The motivation for this change is for analysis tools and IDEs to be
better at analyzing header files on their own.
There are some definitions and includes we want to occur at the very
beginning of all translation units. The way we currently do that is by
requiring all source files (.c and .cc files) to include one of defs.h
(for gdb), server.h (for gdbserver) of common-defs.h (for gdbsupport and
shared source files). These special header files define and include
everything that needs to be included at the very beginning. Other
header files are written in a way that assume that these special
"prologue" header files have already been included.
My problem with that is that my editor (clangd-based) provides a very
bad experience when editing header files. Since clangd doesn't know
that one of defs.h/server.h/common-defs.h was included already, a lot of
things are flagged as errors. For instance, CORE_ADDR is not known.
It's possible to edit the files in this state, but a lot of the power of
the editor is unavailable.
My proposal to help with this is to include those things we always want
to be there using the compilers' `-include` option. Tom Tromey said
that the current approach might exist because not all compilers used to
have an option like this. But I believe that it's safe to assume they
do today.
With this change, clangd picks up the -include option from the compile
command, and is able to analyze the header file correctly, as it sees
all that stuff included or defined by that -include option. That works
because when editing a header file, clangd tries to get the compilation
flags from a source file that includes said header file.
This change is a bit self-serving, because it addresses one of my
frustrations when editing header files, but it might help others too.
I'd be curious to know if others encounter the same kinds of problems
when editing header files. Also, even if the change is not necessary by
any means, I think the solution of using -include for stuff we always
want to be there is more elegant than the current solution.
Even with this -include flag, many header files currently don't include
what they use, but rather depend on files included before them. This
will still cause errors when editing them, but it should be easily
fixable by adding the appropriate include. There's no rush to do so, as
long as the code still compiles, it's just a convenience thing.
The changes are:
- Add the appropriate `-include` option to the various Makefiles.
- There is one particularity for gdbserver's Makefile: we do not want
to include server.h when building `gdbreplay.o`, as `gdbreplay.cc`
doesn't include it. So we can't simply put the `-include` in
`INTERNAL_CFLAGS`. Add the `-include server.h` option to the
`COMPILE` and `IPAGENT_COMPILE` variables, and added a special rule
to compile `gdbreplay.o` with `-include gdbsupport/common-defs.h`.
- Remove the `-include` option from the `check-headers` rule in
gdb/Makefile.in, since it is already included in `INTERNAL_CFLAGS`.
Change-Id: If3e345d00a9fc42336322f1d8286687d22134340
Approved-By: Pedro Alves <pedro@palves.net>
Reformat some variables definitions. I think it makes them easier to
read, and it also makes diffs clearer.
Change-Id: I82f63ba0e6d0fe268eb1f1ad5ab22c3cd016ab02
Approved-By: Pedro Alves <pedro@palves.net>
This patch makes allocate_on_obstack a little bit safer, by enforcing
the rule that objects allocated on an obstack must have a trivial
destructor.
The static assert is done in a method -- doing it inside the class
itself won't work because the class is incomplete at that point.
I noticed in passing that the include guard in the file
gdbsupport/gdb-checked-static-cast.h was wrong, it includes the word
DYNAMIC when STATIC would be better, fixed in this commit.
There should be no user visible changes after this commit.
This commit:
commit 6fe4779ac4
Date: Sat Feb 24 11:00:20 2024 +0100
[gdb/build] Fix static cast of virtual base
addressed an issue where GDB would not compile in production mode due
to a use of gdb::checked_static_cast. The problem was that we were
asking GDB to cast from a virtual base class to a sub-class, this
works fine when using dynamic_cast, but does not work with
static_cast.
The gdb::checked_static_cast actually uses dynamic_cast under the hood
in development mode in order to ensure that the cast is valid, while
in a production build we use static_cast as this is more efficient.
What this meant however, was that when gdb::checked_static_cast was
used to cast from a virtual base class, the dynamic_cast of a
non-production build worked fine, while the production build's
static_cast caused a build failure.
However, the gdb::checked_static_cast function already contains some
static_assert calls that are intended to catch any issues with invalid
type casting, the goal of these asserts was to prevent issues like
this: the build only failing in production mode. Clearly the current
asserts are not enough.
I don't think there is a std::is_virtual_base type trait check, so
what I propose instead is that in non-production mode we also make use
of static_cast. This will ensure that any errors that crop up in
production mode should also be revealed in non-production mode, and
should catch issues like this in the future.
There should be no user visible changes after this commit.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31399
Co-Authored-By: Simon Marchi <simon.marchi@polymtl.ca>
I tried building gdbserver on postmarketos (which is based on alpine linux,
which uses musl libc), and ran into:
...
gdbserver/linux-low.cc: In lambda function:
gdbserver/linux-low.cc:1907:41: error: \
'W_EXITCODE' was not declared in this scope
1907 | mark_lwp_dead (leader_lp, W_EXITCODE (0, 0), true);
| ^~~~~~~~~~
...
The macro W_EXITCODE is not defined in gdbsupport/gdb_wait.h.
OTOH, WSETEXIT is defined there, but unused:
...
/* These are not defined in POSIX, but are used by our programs. */
#ifndef WSETEXIT
# ifdef W_EXITCODE
#define WSETEXIT(w,status) ((w) = W_EXITCODE(status,0))
# else
#define WSETEXIT(w,status) ((w) = (0 | ((status) << 8)))
# endif
#endif
...
Fix this by dropping the WSETEXIT definition, and instead defining W_EXITCODE.
Tested on x86_64-linux, in combination with an "#undef W_EXITCODE" to make
sure the definition is exercised.
Approved-By: Tom Tromey <tom@tromey.com>
PR build/31483
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31483
This patch adds a new function, read_remainder_of_file. This is like
read_text_file_to_string, but reads from an existing 'FILE *'. This
will be used in a subsequent patch.
Reviewed-By: Tom de Vries <tdevries@suse.de>
The GDB build currently fails on x86-64 Cygwin, with:
src/gdbsupport/errors.cc: In function ‘void throw_winerror_with_name(const char*, ULONGEST)’:
src/gdbsupport/errors.cc:152:12: error: format ‘%d’ expects argument of type ‘int’, but argument 3 has type ‘ULONGEST’ {aka ‘long unsigned int’} [-Werror=format=]
152 | error (_("%s (error %d): %s"), string, err, strwinerror (err));
| ^
Fix this by adding a cast. While at it, the error codes are really a
DWORD that results from a GetLastError() call, so I think unsigned is
more appropriate. That is also what strwinerror already does:
sprintf (buf, "unknown win32 error (%u)", (unsigned) error);
The cast is necessary on MinGW GDB as well, where ULONGEST is unsigned
long long, but for some reason, I don't get a warning there.
Approved-By: Tom Tromey <tom@tromey.com>
Change-Id: I3f5faa779765fd8021abf58bb5f68d556b309d17
This code was there to support g++ 4, which didn't support
std::is_trivially_constructible and std::is_trivially_copyable. Since
we now require g++ >= 9, I think it's fair to assume that GDB will
always be compiled with a compiler that supports those.
Change-Id: Ie7c1649139a2f48bf662cac92d7f3e38fb1f1ba1
Since we now require C++17, and therefore gcc >= 9, it's no longer
useful to have gcc version checks for older gcc version.
Change-Id: I3a87baa03c475f2b847b422b16b69c5ff7215b54
Reviewed-by: Kevin Buettner <kevinb@redhat.com>
Approved-By: Pedro Alves <pedro@palves.net>
This commit is the result of the following actions:
- Running gdb/copyright.py to update all of the copyright headers to
include 2024,
- Manually updating a few files the copyright.py script told me to
update, these files had copyright headers embedded within the
file,
- Regenerating gdbsupport/Makefile.in to refresh it's copyright
date,
- Using grep to find other files that still mentioned 2023. If
these files were updated last year from 2022 to 2023 then I've
updated them this year to 2024.
I'm sure I've probably missed some dates. Feel free to fix them up as
you spot them.
This is used by gdb, gdbsupport, and gdbserver. We want to use it
in the sim tree too. Move it to gdbsupport which is meant as the
common sharing space for these projects.
Approved-By: Tom Tromey <tom@tromey.com>
Now that the DWARF reader does not use parallel_for_each, we can
remove some of the features that were added just for it: return values
and task sizing.
The thread_pool typed tasks feature could also be removed, but I
haven't done so here. This one seemed less intrusive and perhaps more
likely to be needed at some point.
clang 16 reports a missing declaration in new-op.cc. We believed
these operators to be declared starting with C++14, but apparently
that is not the case.
This patch reverts the earlier change and then updates the comment to
reflect the current state.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=31141
Change most of regcache (and base classes) to use array_view when
possible, instead of raw pointers. By propagating the use of array_view
further, it enables having some runtime checks to make sure the what we
read from or write to regcaches has the expected length (such as the one
in the `copy(array_view, array_view)` function. It also integrates well
when connecting with other APIs already using gdb::array_view.
Add some overloads of the methods using raw pointers to avoid having to
change all call sites at once (which is both a lot of work and risky).
I tried to do this change in small increments, but since many of these
functions use each other, it ended up simpler to do it in one shot than
having a lot of intermediary / transient changes.
This change extends into gdbserver as well, because there is some part
of the regcache interface that is shared.
Changing the reg_buffer_common interface to use array_view caused some
build failures in nat/aarch64-scalable-linux-ptrace.c. That file
currently "takes advantage" of the fact that
reg_buffer_common::{raw_supply,raw_collect} operates on `void *`, which
IMO is dangerous. It uses raw_supply/raw_collect directly on
uint64_t's, which I guess is fine because it is expected that native
code will have the same endianness as the debugged process. To
accomodate that, add some overloads of raw_collect and raw_supply that
work on uint64_t.
This file also uses raw_collect and raw_supply on `char` pointers.
Change it to use `gdb_byte` pointers instead. Add overloads of
raw_collect and raw_supply that work on `gdb_byte *` and make an
array_view on the fly using the register's size. Those call sites could
be converted to use array_view with not much work, in which case these
overloads could be removed, but I didn't want to do it in this patch, to
avoid starting to dig in arch-specific code.
During development, I inadvertently changed reg_buffer::raw_compare's
behavior to not accept an offset equal to the register size. This
behavior (effectively comparing 0 bytes, returning true) change was
caught by the AArch64 SME core tests. Add a selftest to make sure that
this raw_compare behavior is preserved in the future.
Change-Id: I9005f04114543ddff738949e12d85a31855304c2
Reviewed-By: John Baldwin <jhb@FreeBSD.org>
Right now, gdbsupport/common-regcache.h contains two abstractons for a
regcache. An opaque type `regcache` (gdb and gdbserver both have their
own regcache that is the concrete version of this) and an abstract base
class `reg_buffer_common`, that is the base of regcaches on both sides.
These abstractions allow code to be written for both gdb and gdbserver,
for instance in the gdb/arch sub-directory.
However, having two
different abstractions is impractical. If some common code has a regcache,
and wants to use an operation defined on reg_buffer_common, it can't.
It would be better to have just one. Change all instances of `regcache
*` in gdbsupport/common-regcache.h to be `reg_buffer_common *`, then fix
fallouts.
Implementations in gdb and gdbserver now need to down-cast (using
gdb::checked_static_cast) from reg_buffer_common to their concrete
regcache type. Some of them could be avoided by changing free functions
(like regcache_register_size) to be virtual methods on
reg_buffer_common. I tried it, it seems to work, but I did not include
it in this series to avoid adding unnecessary changes.
Change-Id: Ia5503adb6b5509a0f4604bd2a68b4642cc5283fd
Reviewed-by: John Baldwin <jhb@FreeBSD.org>
This commit enables the early initialization commands (92e4e97a9f) to
modify the number of threads used by gdb's thread pool.
The motivation here is to prevent gdb from spawning a detrimental number
of threads on many-core systems under environments with restrictive
ulimits.
With gdb before this commit, the thread pool takes the following sizes:
1. Thread pool size is initialized to 0.
2. After the maintenance commands are defined, the thread pool size is
set to the number of system cores (if it has not already been set).
3. Using early initialization commands, the thread pool size can be
changed using "maint set worker-threads".
4. After the first prompt, the thread pool size can be changed as in the
previous step.
Therefore after step 2. gdb has potentially launched hundreds of threads
on a many-core system.
After this change, step 2 and 3 are reversed so there is an opportunity
to set the required number of threads without needing to default to the
number of system cores first.
There does exist a configure option (added in 261b07488b) to disable
multithreading, but this does not allow for an already deployed gdb to
be configured.
Additionally, the default number of worker threads is clamped at eight
to control the number of worker threads spawned on many-core systems.
This value was chosen as testing recorded on bugzilla issue 29959
indicates that parallel efficiency drops past this point.
GDB built with GCC 13.
No test suite regressions detected. Compilers: GCC, ACfL, Intel, Intel
LLVM, NVHPC; Platforms: x86_64, aarch64.
The scenario that interests me the most involves preventing GDB from
spawning any worker threads at all. This was tested by counting the
number of clones observed by strace:
strace -e clone,clone3 gdb/gdb -q \
--early-init-eval-command="maint set worker-threads 0" \
-ex q ./gdb/gdb |& grep --count clone
The new test relies on "gdb: install CLI uiout while processing early
init files" developed by Andrew Burgess. This patch will need pushing
prior to this change.
The clamping was tested on machines with both 16 cores and a single
core. "maint show worker-threads" correctly reported eight and one
respectively.
Approved-By: Tom Tromey <tom@tromey.com>
gdbsupport/scope-exit.h has a couple of comments about being able to
rely on copy elision in C++17. This patch makes the change.
Approved-By: Pedro Alves <pedro@palves.net>
