This commit is the result of running the gdb/copyright.py script,
which automated the update of the copyright year range for all
source files managed by the GDB project to be updated to include
year 2023.
Add a version of buffer_xml_printf (defined in gdbsupport/buffer.{c,h})
that appends to an std::string, rather than a struct buffer. Call it
"string" rather than "buffer" since it operates on an std::string rather
than a buffer. And call it "appendf" rather than "printf", since it
appends to and does not replace the string's content. This mirrors
string_appendf.
Place the new version in gdbsupport/xml-utils.h.
The code is a direct copy of buffer_xml_printf. The old version is
going to disappear at some point, which is why I didn't do any effort to
share code.
Change-Id: I30e030627ab4970fd0b9eba3b7e8cec78fa561ba
Approved-By: Pedro Alves <pedro@palves.net>
It seems to me that streq and compare_cstrings belong near the other
string utility functions in common-utils.h; and furthermore that streq
ought to be inlined. This patch makes this change.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
After the previous commit converted symbol-lookup debug to use the new
debug scheme, this commit adds SYMBOL_LOOKUP_SCOPED_DEBUG_ENTER_EXIT.
The previous commit didn't add SYMBOL_LOOKUP_SCOPED_DEBUG_ENTER_EXIT
because symbol-lookup debug is controlled by an 'unsigned int' rather
than a 'bool' control variable, we use the numeric value to offer
different levels of verbosity for symbol-lookup debug.
The *_SCOPED_DEBUG_ENTER_EXIT mechanism currently relies on capturing
a reference to the bool control variable, and evaluating the variable
both on entry, and at exit, this is done in the scoped_debug_start_end
class (see gdbsupport/common-debug.h).
This commit templates scoped_debug_start_end so that the class can
accept either a 'bool &' or an invokable object, e.g. a lambda
function, or a function pointer.
The existing scoped_debug_start_end and scoped_debug_enter_exit macros
in common-debug.h are updated to support scoped_debug_enter_exit being
templated, however, nothing outside of common-debug.h needs to change.
I've then added SYMBOL_LOOKUP_SCOPED_DEBUG_ENTER_EXIT in symtab.h, and
added a couple of token uses in symtab.c. I didn't want to add too
much in this first commit, this is really about updating
common-debug.h to support this new functionality.
Within symtab.h I created a couple of global functions that can be
used to query the status of the symbol_lookup_debug control variable,
these functions are then used within the two existing macros:
symbol_lookup_debug_printf
symbol_lookup_debug_printf_v
and also in the new SYMBOL_LOOKUP_SCOPED_DEBUG_ENTER_EXIT macro.
valgrind reports a leak when assigning a gdb_environ to another gdb_environ.
The memory allocated for the target gdb_environ env variables is not released.
The gdb_environ selftest reproduces the leak (see below).
Fix the leak by clearing the target gdb_environ before std::move-ing the
members.
Tested natively and re-running all tests under valgrind.
==3261873== 4,842 bytes in 69 blocks are definitely lost in loss record 6,772 of 6,839
==3261873== at 0x483979B: malloc (vg_replace_malloc.c:393)
==3261873== by 0x25A454: xmalloc (alloc.c:57)
==3261873== by 0x7D1E4E: xstrdup (xstrdup.c:34)
==3261873== by 0x7E2A51: gdb_environ::from_host_environ() (environ.cc:56)
==3261873== by 0x66F1C8: test_reinit_from_host_environ (environ-selftests.c:78)
==3261873== by 0x66F1C8: selftests::gdb_environ_tests::run_tests() (environ-selftests.c:285)
==3261873== by 0x7EFC43: operator() (std_function.h:622)
=
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Add a new convenience variable $_inferior_thread_count that contains
the number of live (non-exited) threads in the current inferior. This
can be used in command scripts, or breakpoint conditions, etc to
adjust the behaviour for multi-threaded inferiors.
This value is only stable in all-stop mode. In non-stop mode, where
new threads can be started, and existing threads exit, at any time,
this convenience variable can give a different value each time it is
evaluated.
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.
I would like to add more code to nat/linux-osdata.c that reads an entire
file from /proc or /sys and processes it as a string afterwards. I
would like to avoid duplicating the somewhat error-prone code that reads
an entire file to a buffer. I think we should have a utility function
that does that.
Add read_file_to_string to gdbsupport/filestuff.{c,h}, and make
linux_common_core_of_thread use it. I want to make the new function
return an std::string, and because strtok doesn't play well with
std::string (it requires a `char *`, std::string::c_str returns a `const
char *`), change linux_common_core_of_thread to use std::string methods
instead.
Approved-By: Tom Tromey <tom@tromey.com>
Change-Id: I1793fda72a82969c28b944a84acb953f74c9230a
Currently, every internal_error call must be passed __FILE__/__LINE__
explicitly, like:
internal_error (__FILE__, __LINE__, "foo %d", var);
The need to pass in explicit __FILE__/__LINE__ is there probably
because the function predates widespread and portable variadic macros
availability. We can use variadic macros nowadays, and in fact, we
already use them in several places, including the related
gdb_assert_not_reached.
So this patch renames the internal_error function to something else,
and then reimplements internal_error as a variadic macro that expands
__FILE__/__LINE__ itself.
The result is that we now should call internal_error like so:
internal_error ("foo %d", var);
Likewise for internal_warning.
The patch adjusts all calls sites. 99% of the adjustments were done
with a perl/sed script.
The non-mechanical changes are in gdbsupport/errors.h,
gdbsupport/gdb_assert.h, and gdb/gdbarch.py.
Approved-By: Simon Marchi <simon.marchi@efficios.com>
Change-Id: Ia6f372c11550ca876829e8fd85048f4502bdcf06
I get this diff when re-generating configure, probably leftover from
67d1991b78 ("egrep in binutils").
Change-Id: I759c88c2bad648736d33ff98089db45c9b686356
gdb_bfd.c and remote.c contain identical implementations of a
fileio_error -> errno function. Factor that out to
gdbsupport/fileio.{h,cc}.
Rename it fileio_error_to_host, for symmetry with host_to_fileio_error.
Change-Id: Ib9b8807683de2f809c94a5303e708acc2251a0df
Converting from free-form macros to an enum gives a bit of type-safety.
This caught places where we would assign host error numbers to what
should contain a target fileio error number, for instance in
target_fileio_pread.
I added the FILEIO_SUCCESS enumerator, because
remote.c:remote_hostio_parse_result initializes the remote_errno output
variable to 0. It seems better to have an explicit enumerator than to
assign a value for which there is no enumerator. I considered
initializing this variable to FILEIO_EUNKNOWN instead, such that if the
remote side replies with an error and omits the errno value, we'll get
an errno that represents an error instead of 0 (which reprensents no
error). But it's not clear what the consequences of that change would
be, so I prefer to err on the side of caution and just keep the existing
behavior (there is no intended change in behavior with this patch).
Note that remote_hostio_parse_resul still reads blindly what the remote
side sends as a target errno into this variable, so we can still end up
with a nonsensical value here. It's not good, but out of the scope of
this patch.
Convert host_to_fileio_error and fileio_errno_to_host to return / accept
a fileio_error instead of an int, and cascade the change in the whole
chain that uses that.
Change-Id: I454b0e3fcf0732447bc872252fa8e57d138b0e03
I don't see why include/gdb/fileio.h is placed there. It's not
installed by "make install", and it's not included by anything outside
of gdb/gdbserver/gdbsupport.
Move its content back to gdbsupport/fileio.h. I have omitted the bits
inside an `#if 0`, since it's obviously not used, as well as the
"limits" constants, which are also unused.
Change-Id: I6fbc2ea10fbe4cfcf15f9f76006b31b99c20e5a9
When a GDB built with -D_GLIBCXX_DEBUG=1 reads a binary with a single
character name, we hit this assertion failure:
$ ./gdb -q --data-directory=data-directory -nx ./x
/usr/include/c++/12.1.0/string_view:239: constexpr const std::basic_string_view<_CharT, _Traits>::value_type& std::basic_string_view<_CharT, _Traits>::operator[](size_type) const [with _CharT = char; _Traits = std::char_traits<char>; const_reference = const char&; size_type = long unsigned int]: Assertion '__pos < this->_M_len' failed.
The backtrace:
#3 0x00007ffff6c0f002 in std::__glibcxx_assert_fail (file=<optimized out>, line=<optimized out>, function=<optimized out>, condition=<optimized out>) at /usr/src/debug/gcc/libstdc++-v3/src/c++11/debug.cc:60
#4 0x000055555da8a864 in std::basic_string_view<char, std::char_traits<char> >::operator[] (this=0x7fffffffcc30, __pos=1) at /usr/include/c++/12.1.0/string_view:239
#5 0x00005555609dcb88 in path_join[abi:cxx11](gdb::array_view<std::basic_string_view<char, std::char_traits<char> > const>) (paths=...) at /home/simark/src/binutils-gdb/gdbsupport/pathstuff.cc:203
#6 0x000055555e0443f4 in path_join<char const*, char const*> () at /home/simark/src/binutils-gdb/gdb/../gdbsupport/pathstuff.h:84
#7 0x00005555609dc336 in gdb_realpath_keepfile[abi:cxx11](char const*) (filename=0x6060000a8d40 "/home/simark/build/binutils-gdb-one-target/gdb/./x") at /home/simark/src/binutils-gdb/gdbsupport/pathstuff.cc:122
#8 0x000055555ebd2794 in exec_file_attach (filename=0x7fffffffe0f9 "./x", from_tty=1) at /home/simark/src/binutils-gdb/gdb/exec.c:471
#9 0x000055555f2b3fb0 in catch_command_errors (command=0x55555ebd1ab6 <exec_file_attach(char const*, int)>, arg=0x7fffffffe0f9 "./x", from_tty=1, do_bp_actions=false) at /home/simark/src/binutils-gdb/gdb/main.c:513
#10 0x000055555f2b7e11 in captured_main_1 (context=0x7fffffffdb60) at /home/simark/src/binutils-gdb/gdb/main.c:1209
#11 0x000055555f2b9144 in captured_main (data=0x7fffffffdb60) at /home/simark/src/binutils-gdb/gdb/main.c:1319
#12 0x000055555f2b9226 in gdb_main (args=0x7fffffffdb60) at /home/simark/src/binutils-gdb/gdb/main.c:1344
#13 0x000055555d938c5e in main (argc=5, argv=0x7fffffffdcf8) at /home/simark/src/binutils-gdb/gdb/gdb.c:32
The problem is this line in path_join:
gdb_assert (strlen (path) == 0 || !IS_ABSOLUTE_PATH (path));
... where `path` is "x". IS_ABSOLUTE_PATH eventually calls
HAS_DRIVE_SPEC_1:
#define HAS_DRIVE_SPEC_1(dos_based, f) \
((f)[0] && ((f)[1] == ':') && (dos_based))
This macro accesses indices 0 and 1 of the input string. However, `f`
is a string_view of length 1, so it's incorrect to try to access index
1. We know that the string_view's underlying object is a null-terminated
string, so in practice there's no harm. But as far as the string_view
is concerned, index 1 is considered out of bounds.
This patch makes the easy fix, that is to change the path_join parameter
from a vector of to a vector of `const char *`. Another solution would
be to introduce a non-standard gdb::cstring_view class, which would be a
view over a null-terminated string. With that class, it would be
correct to access index 1, it would yield the NUL character. If there
is interest in having this class (it has been mentioned a few times in
the past) I can do it and use it here.
This was found by running tests such as gdb.ada/arrayidx.exp, which
produce 1-char long filenames, so adding a new test is not necessary.
Change-Id: Ia41a16c7243614636b18754fd98a41860756f7af
Commit 171fba11ab ("Make GDBserver abort on internal error in development mode")
created a new substitution CONFIG_STATUS_DEPENDENCIES but this is used by
Makefile.in (which is not regenerated by that commit). After regenerating
it, it is found that CONFIG_STATUS_DEPENDENCIES value is not valid, making
gdbsupport fail to build.
Since the CONFIG_STATUS_DEPENDENCIES value is used in the Makefile, macro
substitution must have a Makefile format but commit 171fba11ab used shell
format "$srcdir/../bfd/development.sh".
This commit fixes this issue by substituting "$srcdir" (shell format) to
"$(srcdir)" (Makefile format). It preserves the dependency as Pedro
intended and fixes the build problem.
It also regenerates corresponding files with the maintainer mode.
gdbsupport/ChangeLog:
* configure.ac: Fix config.status dependency.
* Makefile.in: Regenerate.
* configure: Regenerate.
When building with Clang 14 (using gcc 12 libstdc++ headers), I get:
CXX dwarf2/read.o
In file included from /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:94:
/home/simark/src/binutils-gdb/gdb/../gdbsupport/parallel-for.h:142:21: error: 'result_of<(lambda at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:7124:5) (__gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter> *, std::__cxx1998::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>>, std::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>, std::random_access_iterator_tag>, __gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter> *, std::__cxx1998::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>>, std::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>, std::random_access_iterator_tag>)>' is deprecated: use 'std::invoke_result' instead [-Werror,-Wdeprecated-declarations]
= typename std::result_of<RangeFunction (RandomIt, RandomIt)>::type;
^
/home/simark/src/binutils-gdb/gdb/dwarf2/read.c:7122:14: note: in instantiation of function template specialization 'gdb::parallel_for_each<__gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter> *, std::__cxx1998::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>>, std::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>, std::random_access_iterator_tag>, (lambda at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:7124:5)>' requested here
= gdb::parallel_for_each (1, per_bfd->all_comp_units.begin (),
^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/12.1.1/../../../../include/c++/12.1.1/type_traits:2597:9: note: 'result_of<(lambda at /home/simark/src/binutils-gdb/gdb/dwarf2/read.c:7124:5) (__gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter> *, std::__cxx1998::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>>, std::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>, std::random_access_iterator_tag>, __gnu_debug::_Safe_iterator<__gnu_cxx::__normal_iterator<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter> *, std::__cxx1998::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>>, std::vector<std::unique_ptr<dwarf2_per_cu_data, dwarf2_per_cu_data_deleter>>, std::random_access_iterator_tag>)>' has been explicitly marked deprecated here
{ } _GLIBCXX17_DEPRECATED_SUGGEST("std::invoke_result");
^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/12.1.1/../../../../include/c++/12.1.1/x86_64-pc-linux-gnu/bits/c++config.h:120:45: note: expanded from macro '_GLIBCXX17_DEPRECATED_SUGGEST'
# define _GLIBCXX17_DEPRECATED_SUGGEST(ALT) _GLIBCXX_DEPRECATED_SUGGEST(ALT)
^
/usr/bin/../lib64/gcc/x86_64-pc-linux-gnu/12.1.1/../../../../include/c++/12.1.1/x86_64-pc-linux-gnu/bits/c++config.h:96:19: note: expanded from macro '_GLIBCXX_DEPRECATED_SUGGEST'
__attribute__ ((__deprecated__ ("use '" ALT "' instead")))
^
It complains about the use of std::result_of, which is deprecated in
C++17 and removed in C++20:
https://en.cppreference.com/w/cpp/types/result_of
Given we'll have to transition to std::invoke_result eventually, make a
GDB wrapper to mimimc std::invoke_result, which uses std::invoke_result
for C++ >= 17 and std::result_of otherwise. This way, it will be easy
to remove the wrapper in the future, just replace gdb:: with std::.
Tested by building with gcc 12 in -std=c++11 and -std=c++17 mode, and
clang in -std=c++17 mode (I did not test fully with clang in -std=c++11
mode because there are other unrelated issues).
Change-Id: I50debde0a3307a7bc67fcf8fceefda51860efc1d
Similar to 911438f9f4 ("gdbsupport: fix array-view compilation with
c++11 && _GLIBCXX_DEBUG"), but for gdb::optional.
I get this error when building with Clang 14 and -std=c++11:
CXX agent.o
In file included from /home/simark/src/binutils-gdb/gdbsupport/agent.cc:20:
In file included from /home/simark/src/binutils-gdb/gdbsupport/common-defs.h:210:
In file included from /home/simark/src/binutils-gdb/gdbsupport/common-debug.h:23:
/home/simark/src/binutils-gdb/gdbsupport/../gdbsupport/gdb_optional.h:213:5: error: use of this statement in a constexpr function is a C++14 extension [-Werror,-Wc++14-extensions]
gdb_assert (this->has_value ());
^
/home/simark/src/binutils-gdb/gdbsupport/gdb_assert.h:35:3: note: expanded from macro 'gdb_assert'
((void) ((expr) ? 0 : \
^
Change-Id: If0cf55607fc9dbd1925ccb97cd9abbf8993ff264
Factor out the code that checks that a value is yes/no or yes/no/auto.
Add two macros to gdbsupport/common.m4 and use them in gdb/configure.ac
I inspected the changes to configure. Other than whitespace changes, we
have some benign changes to the error messages (one of them had an error
actually). There are changes to the --enable-source-highlight and
--enable-libbacktrace handling, but setting enable_source_highlight /
enable_libbacktrace was not really useful anyway, they already had the
right value.
Change-Id: I92587aec36874309e1605e2d60244649f09a757a
Since commit b2d8657, having a per-interpreter event/command loop is not
possible anymore.
As Insight uses a GUI that has its own event loop, gdb and GUI event
loops have then to be "merged" (i.e.: work together). But this is
problematic as gdb_do_one_event is not aware of this alternate event
loop and thus may wait forever.
A solution is to delegate GUI events handling to the gdb events handler.
Insight uses Tck/Tk as GUI and the latter offers a "notifier" feature to
implement such a delegation. The Tcl notifier spec requires the event wait
function to support a timeout parameter. Unfortunately gdb_do_one_event
does not feature such a parameter.
This timeout cannot be implemented externally with a gdb timer, because
it would become an event by itself and thus can cause a legitimate event to
be missed if the timeout is 0.
Tcl implements "idle events" that are (internally) triggered only when no
other event is pending. For this reason, it can call the event wait function
with a 0 timeout quite often.
This patch implements a wait timeout to gdb_do_one_event. The initial
pending events monitoring is performed as before without the possibility
to enter a wait state. If no pending event has been found during this
phase, a timer is then created for the given timeout in order to re-use
the implemented timeout logic and the event wait is then performed.
This "internal" timer only limits the wait time and should never be triggered.
It is deleted upon gdb_do_one_event exit.
The new parameter defaults to "no timeout" (-1): as it is used by Insight
only, there is no need to update calls from the gdb source tree.
When working on windows-nat.c, it's useful to see an error message in
addition to the error number given by GetLastError. This patch moves
strwinerror from gdbserver to gdbsupport, and then updates
windows-nat.c to use it. A couple of minor changes to strwinerror
(constify the return type and use the ARRAY_SIZE macro) are also
included.
Add a task_size parameter to parallel_for_each, defaulting to nullptr, and use
the task size to distribute similarly-sized chunks to the threads.
Tested on x86_64-linux.
This adds gdb::make_function_view, which lets you create a function
view from a callable without specifying the function_view's template
parameter. For example, this:
auto lambda = [&] (int) { ... };
auto fv = gdb::make_function_view (lambda);
instead of:
auto lambda = [&] (int) { ... };
gdb::function_view<void (int)> fv = lambda;
It is particularly useful if you have a template function with an
optional function_view parameter, whose type depends on the function's
template parameters. Like:
template<typename T>
void my_function (T v, gdb::function_view<void(T)> callback = nullptr);
For such a function, the type of the callback argument you pass must
already be a function_view. I.e., this wouldn't compile:
auto lambda = [&] (int) { ... };
my_function (1, lambda);
With gdb::make_function_view, you can write the call like so:
auto lambda = [&] (int) { ... };
my_function (1, gdb::make_function_view (lambda));
Unit tests included.
Tested by building with GCC 9.4, Clang 10, and GCC 4.8.5, on x86_64
GNU/Linux, and running the unit tests.
Change-Id: I5c4b3b4455ed6f0d8878cf1be189bea3ee63f626
When debugging cc1 I heavily rely on simple one-parameter debug functions
that allow me to inspect a variable of a common type, like:
- debug_generic_expr
- debug_gimple_stmt
- debug_rtx
and I miss similar functions in gdb.
Add functions to dump variables of types 'value' and 'expression':
- debug_exp, and
- debug_val.
Tested on x86_64-linux, by breaking on varobj_create, and doing:
...
(gdb) call debug_exp (var->root->exp.get ())
&"Operation: OP_VAR_VALUE\n"
&" Block symbol:\n"
&" Symbol: aaa\n"
&" Block: 0x2d064f0\n"
(gdb)
...
and:
...
(gdb) call debug_val (value)
&"5"
(gdb)
...
Attribute gcc_struct is not implemented in Clang targeting Windows, so
add a fallback standard-conforming implementation based on arrays.
I ran the testsuite on x86_64 GNU/Linux with this implementation
forced, and saw no regressions.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29373
Change-Id: I023315ee03622c59c397bf4affc0b68179c32374
For PR gdb/29373, I wrote an alternative implementation of struct
packed that uses a gdb_byte array for internal representation, needed
for mingw+clang. While adding that, I wrote some unit tests to make
sure both implementations behave the same. While at it, I implemented
all relational operators. This commit adds said unit tests and
relational operators. The alternative gdb_byte array implementation
will come next.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29373
Change-Id: I023315ee03622c59c397bf4affc0b68179c32374
Building GDB on mingw/gcc hosts is currently broken, due to a static
assertion failure in gdbsupport/packed.h:
In file included from ../../../../../binutils-gdb/gdb/../gdbsupport/common-defs.h:201,
from ../../../../../binutils-gdb/gdb/defs.h:28,
from ../../../../../binutils-gdb/gdb/dwarf2/read.c:31:
../../../../../binutils-gdb/gdb/../gdbsupport/packed.h: In instantiation of 'packed<T, Bytes>::packed(T) [with T = dwarf_unit_type; long long unsigned int Bytes = 1]':
../../../../../binutils-gdb/gdb/dwarf2/read.h:181:74: required from here
../../../../../binutils-gdb/gdb/../gdbsupport/packed.h:41:40: error: static assertion failed
41 | gdb_static_assert (sizeof (packed) == Bytes);
| ~~~~~~~~~~~~~~~~^~~~~~~~
../../../../../binutils-gdb/gdb/../gdbsupport/gdb_assert.h:27:48: note: in definition of macro 'gdb_static_assert'
27 | #define gdb_static_assert(expr) static_assert (expr, "")
| ^~~~
../../../../../binutils-gdb/gdb/../gdbsupport/packed.h:41:40: note: the comparison reduces to '(4 == 1)'
41 | gdb_static_assert (sizeof (packed) == Bytes);
| ~~~~~~~~~~~~~~~~^~~~~~~~
The issue is that mingw gcc defaults to "-mms-bitfields", which
affects how bitfields are laid out. We can however tell GCC that we
want the regular GCC layout instead using attribute gcc_struct.
Attribute gcc_struct is not implemented in "clang -target
x86_64-pc-windows-gnu", so that will need a different fix.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29373
Change-Id: I023315ee03622c59c397bf4affc0b68179c32374
This commit was inspired by these mailing list posts:
https://sourceware.org/pipermail/gdb-patches/2022-June/190323.htmlhttps://sourceware.org/pipermail/gdb-patches/2022-April/188098.html
The idea is to add a new function gdb::checked_static_cast, which can,
in some cases, be used as a drop-in replacement for static_cast. And
so, if I previously wrote this:
BaseClass *base = get_base_class_pointer ();
DerivedClass *derived = static_cast<DerivedClass *> (base);
I can now write:
BaseClass *base = get_base_class_pointer ();
DerivedClass *derived = gdb::checked_static_cast<DerivedClass *> (base);
The requirement is that BaseClass and DerivedClass must be
polymorphic.
The benefit of making this change is that, when GDB is built in
developer mode, a run-time check will be made to ensure that `base`
really is of type DerivedClass before the cast is performed. If
`base` is not of type DerivedClass then GDB will assert.
In a non-developer build gdb::checked_static_cast is equivalent to a
static_cast, and there should be no performance difference.
This commit adds the support function, but does not make use of this
function, a use will be added in the next commit.
Co-Authored-By: Pedro Alves <pedro@palves.net>
Co-Authored-By: Tom Tromey <tom@tromey.com>
When I changed the initialization of parallel_for_each_debug from 0 to false,
I forgot to change the type from int to bool. Fix this.
Tested by rebuilding on x86_64-linux.
When running a task using parallel_for_each, we get the following
distribution:
...
Parallel for: n_elements: 7271
Parallel for: minimum elements per thread: 10
Parallel for: elts_per_thread: 1817
Parallel for: elements on worker thread 0 : 1817
Parallel for: elements on worker thread 1 : 1817
Parallel for: elements on worker thread 2 : 1817
Parallel for: elements on worker thread 3 : 0
Parallel for: elements on main thread : 1820
...
Note that there are 4 active threads, and scheduling elts_per_thread on each
of those handles 4 * 1817 == 7268, leaving 3 "left over" elements.
These leftovers are currently handled in the main thread.
That doesn't seem to matter much for this example, but for say 10 threads and
99 elements, you'd have 9 threads handling 9 elements and 1 thread handling 18
elements.
Instead, distribute the left over elements over the worker threads, such that
we have:
...
Parallel for: elements on worker thread 0 : 1818
Parallel for: elements on worker thread 1 : 1818
Parallel for: elements on worker thread 2 : 1818
Parallel for: elements on worker thread 3 : 0
Parallel for: elements on main thread : 1817
...
Tested on x86_64-linux.
Add a parallel_for_each_debug variable, set to false by default.
With an a.out compiled from hello world, we get with
parallel_for_each_debug == true:
...
$ gdb -q -batch a.out -ex start
...
Parallel for: n_elements: 7271
Parallel for: minimum elements per thread: 10
Parallel for: elts_per_thread: 1817
Parallel for: elements on worker thread 0 : 1817
Parallel for: elements on worker thread 1 : 1817
Parallel for: elements on worker thread 2 : 1817
Parallel for: elements on worker thread 3 : 0
Parallel for: elements on main thread : 1820
Temporary breakpoint 1, main () at /home/vries/hello.c:6
6 printf ("hello\n");
...
Tested on x86_64-linux.
Add a sequential_for_each alongside the parallel_for_each, which can be used
as a drop-in replacement.
This can be useful when debugging multi-threading behaviour, and you want to
limit multi-threading in a fine-grained way.
Tested on x86_64-linux, by using it instead of the parallel_for_each in
dwarf2_build_psymtabs_hard.
When building gdb with gcc 4.8.5, we run into:
...
In file included from /usr/include/c++/4.8/future:43:0,
from gdbsupport/thread-pool.h:30,
from gdb/dwarf2/cooked-index.h:33,
from gdb/dwarf2/read.h:26,
from gdb/dwarf2/abbrev-cache.c:21:
/usr/include/c++/4.8/atomic: In instantiation of \
‘_Tp std::atomic<_Tp>::load(std::memory_order) const [with _Tp = \
packed<dwarf_unit_type, 1ul>; std::memory_order = std::memory_order]’:
gdb/dwarf2/read.h:332:44: required from here
/usr/include/c++/4.8/atomic:208:13: error: no matching function for call to \
‘packed<dwarf_unit_type, 1ul>::packed()’
_Tp tmp;
^
...
Fix this by adding the default constructor for packed.
Tested on x86_64-linux, with gdb build with gcc 4.8.5.
When building gdb with gcc 4.8.5, we run into problems due to unconditionally
using:
...
gdb_static_assert (std::is_trivially_copyable<packed>::value);
...
in gdbsupport/packed.h.
Fix this by guarding the usage with HAVE_IS_TRIVIALLY_COPYABLE.
Tested by doing a full gdb build with gcc 4.8.5.
When building gdb with -fsanitize=thread and gcc 12, and running test-case
gdb.dwarf2/dwz.exp, we run into a few data races. For example, between:
...
Write of size 1 at 0x7b200000300e by thread T4:
#0 process_psymtab_comp_unit gdb/dwarf2/read.c:6789 (gdb+0x830720)
...
and:
...
Previous read of size 1 at 0x7b200000300e by main thread:
#0 cutu_reader::cutu_reader(dwarf2_per_cu_data*, dwarf2_per_objfile*, \
abbrev_table*, dwarf2_cu*, bool, abbrev_cache*) gdb/dwarf2/read.c:6164 \
(gdb+0x82edab)
...
In other words, between:
...
this_cu->unit_type = DW_UT_partial;
...
and:
...
if (this_cu->reading_dwo_directly)
...
The problem is that the written fields are part of the same memory
location as the read fields, so executing a read and write in
different threads is undefined behavour.
Making the written fields separate memory locations, like this:
...
struct {
ENUM_BITFIELD (dwarf_unit_type) unit_type : 8;
};
...
fixes it, however that also increases the size of struct
dwarf2_per_cu_data, because it introduces padding due to alignment of
these new structs, which align on the natural alignment of the
specified type of their fields. We can fix that with
__attribute__((packed)), like so:
struct {
ENUM_BITFIELD (dwarf_unit_type) unit_type : 8 __attribute__((packed));
};
but to avoid having to write that in several places and add suitable
comments explaining how that concoction works, introduce a new struct
packed template that wraps/hides this. Instead of the above, we'll be
able to write:
packed<dwarf_unit_type, 1> unit_type;
Note that we can't change the type of dwarf_unit_type, as that is
defined in include/, and shared with other projects, some of those
written in C.
This patch just adds the struct packed type. Following patches will
make use of it. One of those patches will want to wrap a struct
packed in an std::atomic, like:
std::atomic<std::packed<language, 1>> m_lang;
so the new gdbsupport/packed.h header adds some operators to make
comparisions between that std::atomic and the type that the wrapped
struct packed wraps work, like in:
if (m_lang == language_c)
It would be possible to implement struct packed without using
__attribute__((packed)), by having it store an array of bytes of the
appropriate size instead, however that would make it less convenient
to debug GDB. The way it's implemented, printing a struct packed
variable just prints its field using its natural type, which is
particularly useful if the type is an enum. I believe that
__attribute__((packed)) is supported by all compilers that are able to
build GDB. Even a few BFD headers use on ATTRIBUTE_PACKED on external
types:
include/coff/external.h: } ATTRIBUTE_PACKED
include/coff/external.h:} ATTRIBUTE_PACKED ;
include/coff/external.h:} ATTRIBUTE_PACKED ;
include/coff/pe.h:} ATTRIBUTE_PACKED ;
include/coff/pe.h:} ATTRIBUTE_PACKED;
include/elf/external.h:} ATTRIBUTE_PACKED Elf_External_Versym;
It is not possible to build GDB with MSVC today, but if it could, that
would be one compiler that doesn't support this attribute. However,
it supports packing via pragmas, so there's a way to cross that bridge
if we ever get to it. I believe any compiler worth its salt supports
some way of packing.
In any case, the worse that happens without the attribute is that some
types become larger than ideal. Regardless, I've added a couple
static assertions to catch such compilers in action:
/* Ensure size and aligment are what we expect. */
gdb_static_assert (sizeof (packed) == Bytes);
gdb_static_assert (alignof (packed) == 1);
Change-Id: Ifa94f0a2cebfae5e8f6ddc73265f05e7fd9e1532
With gdb build with gcc-12 and -fsanitize=thread, and test-case
gdb.base/gdb-sigterm.exp, I run into:
...
WARNING: ThreadSanitizer: data race (pid=9722)^M
Write of size 4 at 0x00000325bc68 by thread T1:^M
#0 handle_sigterm(int) src/gdb/event-top.c:1211 (gdb+0x8ec01f)^M
...
Previous read of size 4 at 0x00000325bc68 by main thread:^M
[failed to restore the stack]^M
^M
Location is global 'sync_quit_force_run' of size 4 at \
0x00000325bc68 (gdb+0x325bc68)^M
...
SUMMARY: ThreadSanitizer: data race gdb/event-top.c:1211 in \
handle_sigterm(int)^M
...
and 3 more data races involving handle_sigterm and locations:
- active_ext_lang
- quit_flag
- heap block of size 40
(XNEW (async_signal_handler) in create_async_signal_handler)
This was reported in PR29297.
The testcase executes a "kill -TERM $gdb_pid", which generates a
process-directed signal.
A process-directed signal can be delivered to any thread, and what we see
here is the fallout of the signal being delivered to a worker thread rather
than the main thread.
Fix this by blocking SIGTERM in the worker threads.
[ I have not been able to reproduce this after it occurred for the first time,
so unfortunately I cannot confirm that the patch fixes the problem. ]
Tested on x86_64-linux, with and without -fsanitize=thread.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29297
Currently, if GDBserver hits some internal assertion, it exits with
error status, instead of aborting. This makes it harder to debug
GDBserver, as you can't just debug a core file if GDBserver fails an
assertion. I've had to hack the code to make GDBserver abort to debug
something several times before.
I believe the reason it exits instead of aborting, is to prevent
potentially littering the filesystem of smaller embedded targets with
core files. I think I recall Daniel Jacobowitz once saying that many
years ago, but I can't be sure. Anyhow, that seems reasonable to me.
Since we nowadays have a distinction between development and release
modes, I propose to make GDBserver abort on internal error if in
development mode, while keeping the status quo when in release mode.
Thus, after this patch, in development mode, you get:
$ ../gdbserver/gdbserver
../../src/gdbserver/server.cc:3711: A problem internal to GDBserver has been detected.
captured_main: Assertion `0' failed.
Aborted (core dumped)
$
while in release mode, you'll continue to get:
$ ../gdbserver/gdbserver
../../src/gdbserver/server.cc:3711: A problem internal to GDBserver has been detected.
captured_main: Assertion `0' failed.
$ echo $?
1
I do not think that this requires a separate configure switch.
A "--target_board=native-extended-gdbserver" run on Ubuntu 20.04 ends
up with:
=== gdb Summary ===
# of unexpected core files 29
...
for me, of which 8 are GDBserver core dumps, 7 more than without this
patch.
Change-Id: I6861e08ad71f65a0332c91ec95ca001d130b0e9d
After DWARF has been scanned, the cooked index code does a
"finalization" step in a worker thread. This step combines all the
index entries into a single master list, canonicalizes C++ names, and
splits Ada names to synthesize package names.
While this step is run in the background, gdb will wait for the
results in some situations, and it turns out that this step can be
slow. This is PR symtab/29105.
This can be sped up by parallelizing, at a small memory cost. Now
each index is finalized on its own, in a worker thread. The cost
comes from name canonicalization: if a given non-canonical name is
referred to by multiple indices, there will be N canonical copies (one
per index) rather than just one.
This requires changing the users of the index to iterate over multiple
results. However, this is easily done by introducing a new "chained
range" class.
When run on gdb itself, the memory cost seems rather low -- on my
current machine, "maint space 1" reports no change due to the patch.
For performance testing, using "maint time 1" and "file" will not show
correct results. That approach measures "time to next prompt", but
because the patch only affects background work, this shouldn't (and
doesn't) change. Instead, a simple way to make gdb wait for the
results is to set a breakpoint.
Before:
$ /bin/time -f%e ~/gdb/install/bin/gdb -nx -q -batch \
-ex 'break main' /tmp/gdb
Breakpoint 1 at 0x43ec30: file ../../binutils-gdb/gdb/gdb.c, line 28.
2.00
After:
$ /bin/time -f%e ./gdb/gdb -nx -q -batch \
-ex 'break main' /tmp/gdb
Breakpoint 1 at 0x43ec30: file ../../binutils-gdb/gdb/gdb.c, line 28.
0.65
Regression tested on x86-64 Fedora 34.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29105
When building gdb with -fsanitize=undefined, I run into:
...
(gdb) PASS: gdb.ada/access_to_packed_array.exp: set logging enabled on
maint print symbols^M
print-utils.cc:281:29:runtime error: negation of -9223372036854775808 cannot \
be represented in type 'long int'; cast to an unsigned type to negate this \
value to itself
(gdb) FAIL: gdb.ada/access_to_packed_array.exp: maint print symbols
...
By running in a debug session, we find that this happens during printing of:
...
typedef system.storage_elements.storage_offset: \
range -9223372036854775808 .. 9223372036854775807;
...
Possibly, an ada test-case could be created that exercises this in isolation.
The problem is here in int_string, where we negate a val with type LONGEST:
...
return decimal2str ("-", -val, width);
...
Fix this by, as recommend, using "-(ULONGEST)val" instead.
Tested on x86_64-linux.
When building GDB with -std=c++17 and -D_GLIBCXX_DEBUG=1, I get:
$ ./gdb -nx --data-directory=data-directory -q -ex "maint selftest path_join"
/usr/include/c++/11.2.0/string_view:233: constexpr const value_type& std::basic_string_view<_CharT, _Traits>::operator[](std::basic_string_view<_CharT, _Traits>::size_type) const [with _CharT = char; _Traits = std::char_traits<char>; std::basic_string_view<_CharT, _Traits>::const_reference = const char&; std::basic_string_view<_CharT, _Traits>::size_type = long unsigned int]: Assertion '__pos < this->_M_len' failed.
The problem is that we're passing an empty string_view to
IS_ABSOLUTE_PATH. IS_ABSOLUTE_PATH accesses [0] on that string_view,
which is out-of-bounds.
The reason this is not seen with -std less than c++17 is that our local
copy of string_view (used with C++ < 17) does not have the assert in
operator[], as that wouldn't work in a constexpr method:
5890af36e5/gdbsupport/gdb_string_view.h (L180)
IS_ABSOLUTE_PATH is normally used with null-terminated string. It's
fine to pass an empty null-terminated string to IS_ABSOLUTE_PATH,
because index 0 in such a string is valid. But not with an empty
string_view.
Fix that by avoiding the "call" to IS_ABSOLUTE_PATH if the string_view
is empty.
Change-Id: Idf4df961b63f513b3389235e93814c02b89ea32e
The handle_file_event function has a few unnecessary {} lexical
blocks, presumably because they were originally if blocks, and the
conditions were removed, or something along those lines.
Remove the unnecessary blocks, and reindent.
Change-Id: Iaecbe5c9f4940a80b81dbbc42e51ce506f6aafb2
gdbsupport/event-loop.cc throughout handles the case of use_poll being
true on a system where HAVE_POLL is not defined, by calling
internal_error if that situation ever happens.
Simplify this by moving the "use_poll" global itself under HAVE_POLL,
so that it's way more unlikely to ever end up in such a situation.
Then, move the code that checks the value of use_poll under HAVE_POLL
too, and remove the internal_error calls. Like, from:
if (use_poll)
{
#ifdef HAVE_POLL
// poll code
#else
internal_error (....);
#endif /* HAVE_POLL */
}
else
{
// select code
}
to
#ifdef HAVE_POLL
if (use_poll)
{
// poll code
}
else
#endif /* HAVE_POLL */
{
// select code
}
While at it, make use_poll be a bool. The current code is using
unsigned char most probably to save space, but I don't think it really
matters here.
Co-Authored-By: Youling Tang <tangyouling@loongson.cn>
Change-Id: I0dd74fdd4d393ccd057906df4cd75e8e83c1cdb4
PR build/29110 points out that GDB fails to build on mingw when the
"win32" thread model is in use. It turns out that the Fedora cross
tools using the "posix" thread model, which somehow manages to support
std::future, whereas the win32 model does not.
While looking into this, I found that the configuring with
--disable-threading will also cause a build failure.
This patch fixes this build by introducing a compatibility wrapper for
std::future.
I am not able to test the win32 thread model build, but I'm going to
ask the reporter to try this patch.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=29110
The other day, while looking at the symbols that end up in a GDB
index, I noticed that the gdb::observers::observable::visit_state enum
class appears a number of times:
$ grep VISIT gdb-index-symbol-names.txt
gdb::observers::observable<bpstat*, int>::visit_state::NOT_VISITED
gdb::observers::observable<bpstat*, int>::visit_state::VISITED
gdb::observers::observable<bpstat*, int>::visit_state::VISITING
gdb::observers::observable<breakpoint*>::visit_state::NOT_VISITED
gdb::observers::observable<breakpoint*>::visit_state::VISITED
gdb::observers::observable<breakpoint*>::visit_state::VISITING
gdb::observers::observable<char const*, char const*>::visit_state::NOT_VISITED
gdb::observers::observable<char const*, char const*>::visit_state::VISITED
gdb::observers::observable<char const*, char const*>::visit_state::VISITING
gdb::observers::observable<char const*>::visit_state::NOT_VISITED
gdb::observers::observable<char const*>::visit_state::VISITED
gdb::observers::observable<char const*>::visit_state::VISITING
gdb::observers::observable<enum_flags<user_selected_what_flag> >::visit_state::NOT_VISITED
gdb::observers::observable<enum_flags<user_selected_what_flag> >::visit_state::VISITED
gdb::observers::observable<enum_flags<user_selected_what_flag> >::visit_state::VISITING
gdb::observers::observable<frame_info*, int>::visit_state::NOT_VISITED
gdb::observers::observable<frame_info*, int>::visit_state::VISITED
gdb::observers::observable<frame_info*, int>::visit_state::VISITING
gdb::observers::observable<gdbarch*>::visit_state::NOT_VISITED
gdb::observers::observable<gdbarch*>::visit_state::VISITED
gdb::observers::observable<gdbarch*>::visit_state::VISITING
gdb::observers::observable<gdb_signal>::visit_state::NOT_VISITED
gdb::observers::observable<gdb_signal>::visit_state::VISITED
gdb::observers::observable<gdb_signal>::visit_state::VISITING
[... snip ...]
$ grep VISIT gdb-index-symbol-names.txt | wc -l
72
enum class visit_state is defined inside the class template
observable, but it doesn't have to be, as it does not depend on the
template parameters. This commit moves it out, so that only one such
type exists. This reduces the size of a -O0 -g3 build for me by
around 0.6%, like so:
$ du -b gdb.before gdb.after
164685280 gdb.before
163707424 gdb.fixed
and codesize by some 0.5%.
Change-Id: I405f4ef27b8358fdd22158245b145d849b45658e
This fixes build breakage using clang with libc++ on FreeBSD where
std::array<> is not yet declared when used by the path_join variadic
function template.
In this review [1], Eli pointed out that we should be careful when
concatenating file names to avoid duplicated slashes. On Windows, a
double slash at the beginning of a file path has a special meaning. So
naively concatenating "/" and "foo/bar" would give "//foo/bar", which
would not give the desired results. We already have a few spots doing:
if (first_path ends with a slash)
path = first_path + second_path
else
path = first_path + slash + second_path
In general, I think it's nice to avoid superfluous slashes in file
paths, since they might end up visible to the user and look a bit
unprofessional.
Introduce the path_join function that can be used to join multiple path
components together (along with unit tests).
I initially wanted to make it possible to join two absolute paths, to
support the use case of prepending a sysroot path to a target file path,
or the prepending the debug-file-directory to a target file path. But
the code in solib_find_1 shows that it is more complex than this anyway
(for example, when the right hand side is a Windows path with a drive
letter). So I don't think we need to support that case in path_join.
That also keeps the implementation simpler.
Change a few spots to use path_join to show how it can be used. I
believe that all the spots I changed are guarded by some checks that
ensure the right hand side operand is not an absolute path.
Regression-tested on Ubuntu 18.04. Built-tested on Windows, and I also
ran the new unit-test there.
[1] https://sourceware.org/pipermail/gdb-patches/2022-April/187559.html
Change-Id: I0df889f7e3f644e045f42ff429277b732eb6c752
This patch adds a way to delay the registration of tests until the
latest possible moment. This is intended for situations where GDB needs
to be fully initialized in order to decide if a particular selftest can
be executed or not.
This mechanism will be used in the next patch.
Change-Id: I7f6b061f4c0a6832226c7080ab4e3a2523e1b0b0
Remove the callback-based selftests::for_each_selftest function and use
an iterator_range instead.
Also use this iterator range in run_tests so all iterations over the
selftests are done in a consistent way. This will become useful in a
later commit.
Change-Id: I0b3a5349a7987fbcb0071f11c394e353df986583
