All of our custom Python types are created as structs, like this:
struct some_new_type : public PyObject
{
... various fields ...
};
Then instances of this struct are created by calling PyObject_New,
either directly within GDB's C++ code, or within Python when a user's
Python script creates an instance of that class.
The problem is that Python is written in C, and PyObject_New doesn't
call any constructors for `some_new_type`, nor for any of the fields
within `some_new_type`.
If `some_new_type` is Plain Old Data (POD), then this is fine. Or, to
be more C++ specific, if `some_new_type` is trivially default
constructable, then we're fine.
But if a field within `some_new_type` has a non-trivial constructor,
then we're in trouble as that constructor will never be run.
An example of a problematic field type is frame_info_ptr. The
constructor for this type registers the new object with a central
management object, recording the `this` pointer, using this type within
`some_new_type` will not work as expected; frame invalidation will not
show up within the frame_info_ptr as you might expect.
And so, this type trait exists. Whenever a struct is created to define
a new Python type we should add a line like:
static_assert (gdb::is_python_allocatable_v<some_new_type>);
This will fail if any field of `some_new_type` are unsuitable for this
use.
We don't actually check is_trivially_default_constructible here. Some
types, e.g. ui_file_style::color, have non-trivial (or no default)
constructors, but are still safe to use within `some_new_type` because
their constructors just initialise data fields; there's nothing
"special" that the constructor does that cannot be achieved by
assigning the fields after creation with PyObject_New.
What actually matters is that the type is trivially destructible
(Python won't call C++ destructors, so destructors with side effects,
like deregistering from a list, would be skipped) and trivially
copyable (Python may copy objects with memcpy). Types like
frame_info_ptr, whose constructors and destructors have side effects
such as registering with a central management object, will be caught
because they are neither trivially destructible nor trivially copyable.
Simple POD types like ui_file_style are trivially destructible and
copyable, so pass this trait.
This commit adds the new type trait, and makes use of it in all cases
but one, pending_frame_object in python/py-unwind.c, has a field of
type frame_info_ptr, which is currently broken. This will be fixed,
and the static_assert added, in the next commit.
Approved-By: Tom Tromey <tom@tromey.com>
Python extension objects that support __dict__ must inherit from
gdbpy_dict_wrapper, a wrapper class that stores the PyObject
corresponding to the __dict__ attribute. Because this dictionary
is not managed directly by Python, each extension objects must
provide appropriate accessors so that attributes stored in __dict__
are looked up correctly.
Currently, management of this dictionary is not centralized, and
each Python extension object implements its own logic to create,
access, and destroy it.
A previous patch centralized the creation logic; this patch focuses
on centralizing the access to the dictionary. It introduces two new
macros:
- gdbpy_dict_wrapper_cfg_dict_getter, which defines a getter for
__dict__.
- gdbpy_dict_wrapper_getsetattro, which sets tp_getattro and
tp_setattro in PyTypeObject to gdb_py_generic_getattro and
gdb_py_generic_setattro, respectively. These helpers already
centralizes attribute access for Python extension objects having
a __dict__.
Note: this macro will eventually be removed once Python extension
types are migrated to heap-allocated types.
Approved-By: Tom Tromey <tom@tromey.com>
Python extension objects that support __dict__ must inherit from
gdbpy_dict_wrapper, a wrapper class that stores the PyObject
corresponding to the __dict__ attribute.
Currently, management of this dictionary is not centralized, and
each Python extension object implements its own logic to create,
access, and destroy it.
This patch focuses on the allocation of the dictionary, introduces
a new method, gdbpy_dict_wrapper::allocate_dict(), and
adapts the existing code to use this method.
Approved-By: Tom Tromey <tom@tromey.com>
Now that gdb's Python types derive from PyObject, there's no need to
use a template for gdbpy_ref_policy. This simplifies the code a tiny
bit.
Approved-By: Andrew Burgess <aburgess@redhat.com>
Fix a whitespace problem pre-commit complains about:
...
check-whitespace........................................................Failed
- hook id: check-whitespace
- exit code: 2
gdb/python/py-ref.h:58: indent with spaces.
+ "The __dict__ for this object.", nullptr },
...
When enabling the Python limited API, pointers to Python C extension
objects can no longer be implicitly converted to 'PyObject *' by the
compiler.
gdbpy_ref_policy is a templated class that provides a generic interface
for incrementing and decrementing the reference counter on the given
object. It is used as a specialisation of the policy parameter in
gdb::ref_ptr, together with PyObject as the parameter type. As a result,
gdbpy_ref_policy always expects an argument derived from PyObject.
This patch fixes the resulting compilation issue by adding an explicit
static_cast to 'PyObject *' before passing the value to Py_INCREF and
Py_DECREF. As a side effect, these casts enforce, at compile time, that
the template type passed to gdbpy_ref_policy is a subclass of PyObject.
To provide a clearer diagnostic when an incorrect type is used, a
static_assert is added to gdbpy_ref_policy, avoiding obscure errors
originating from the static_cast. Finally, all C Python extension types
passed to gdbpy_ref_policy are updated to inherit from PyObject.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=23830
Approved-By: Tom Tromey <tom@tromey.com>
GDB is currently using the Python unlimited API. Migrating the codebase
to the Python limited API would have for benefit to make a GDB build
artifacts compatible with older and newer versions of Python that they
were built with.
This patch prepares the ground for migrating the existing C extension
types from static types to heap-allocated ones, by removing the
dependency on tp_dictoffset, which is unavailable when using the limited
API.
One of the most common incompatibilities in the current static type
declarations is the tp_dictoffset slot, which specifies the dictionary
offset within the instance structure. Historically, the unlimited
API has provided two approaches to supply a dictionary for __dict__:
* A managed dictionary.
Setting Py_TPFLAGS_MANAGED_DICT in tp_flags indicates that the
instances of the type have a __dict__ attribute, and that the
dictionary is managed by Python.
According to the Python documentation, this is the recommended approach.
However, this flag was introduced in 3.12, together with
PyObject_VisitManagedDict() and PyObject_ClearManagedDict(), neither
of which is part of the limited API (at least for now). As a result,
this recommended approach is not viable in the context of the limited
API.
* An instance dictionary, for which the offset in the instance is
provided via tp_dictoffset.
According to the Python documentation, this "tp slot" is on the
deprecation path, and Py_TPFLAGS_MANAGED_DICT should be used instead.
Given the age of the GDB codebase and the requirement to support older
Python versions (>= 3.4), no need to argue that today, the implementation
of __dict__ relies on tp_dictoffset. However, in the context of the
limited API, PyType_Slot does not provide a Py_tp_dictoffset member, so
another approach is needed to provide __dict__ to instances of C extension
types.
Given the constraints of the limited API, the proposed solution consists
in providing a dictionary through a common base class, gdbpy__dict__wrapper.
This helper class owns a dictionary member corresponding to __dict__, and
any C extension type requiring a __dict__ must inherit from it. Since
extension object must also be convertible to PyObject, this wrapper class
publicly inherits from PyObject as well.
Access to the dictionary is provided via a custom getter defined in a
PyGetSetDef, similarily to what was previously done with gdb_py_generic_dict().
Because __dict__ participates in attribute look-up, and since this dictionary
is neither managed by Python nor exposed via tp_dictoffset, custom
implementations of tp_getattro and tp_setattro are required to correctly
redirect attribute look-ups to the dictionary. These custom implementations
— equivalent to PyObject_GenericGetAttr() and PyObject_GenericSetAttr() —
must be installed via tp_getattro / tp_setattro for static types, or
Py_tp_getattro / Py_tp_setattro for heap-allocated types.
- gdbpy__dict__wrapper: a base class for C extension objects that own a
__dict__.
- gdb_py_generic_dict_getter: a __dict__ getter for extension types
derived from gdbpy__dict__wrapper.
- gdb_py_generic_getattro: equivalent of PyObject_GenericGetAttr, but
fixes the look-up of __dict__.
- gdb_py_generic_setattro: equivalent of PyObject_GenericSetAttr, but
fixes the look-up of __dict__.
Bug: https://sourceware.org/bugzilla/show_bug.cgi?id=23830
Approved-By: Tom Tromey <tom@tromey.com>
This updates the copyright headers to include 2026. I did this by
running gdb/copyright.py and then manually modifying a few files as
noted by the script.
This updates the copyright headers to include 2025. I did this by
running gdb/copyright.py and then manually modifying a few files as
noted by the script.
Approved-By: Eli Zaretskii <eliz@gnu.org>
This patch is the result of running check-include-guards.py on the
current tree. Running it a second time causes no changes.
Reviewed-By: Tom de Vries <tdevries@suse.de>
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 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.
This commit brings all the changes made by running gdb/copyright.py
as per GDB's Start of New Year Procedure.
For the avoidance of doubt, all changes in this commits were
performed by the script.
This commits the result of running gdb/copyright.py as per our Start
of New Year procedure...
gdb/ChangeLog
Update copyright year range in copyright header of all GDB files.
While working on my other scripts to deal with gdb headers, I noticed
that some files were missing include guards. I wrote a script to add
the missing ones, but found that using the obvious names for the
guards ran into clashes -- for example, gdb/nat/linux-nat.h used
"LINUX_NAT_H", but this was also the script's choice for
gdb/linux-nat.h.
So, I changed the script to normalize all include guards in gdb. This
patch is the result.
As usual the script is available here:
https://github.com/tromey/gdb-refactoring-scripts
Tested by rebuilding; I also ran it through "Fedora-x86_64-m64" on the
buildbot.
gdb/ChangeLog
2019-02-07 Tom Tromey <tom@tromey.com>
* yy-remap.h: Add include guard.
* xtensa-tdep.h: Add include guard.
* xcoffread.h: Rename include guard.
* varobj-iter.h: Add include guard.
* tui/tui.h: Rename include guard.
* tui/tui-winsource.h: Rename include guard.
* tui/tui-wingeneral.h: Rename include guard.
* tui/tui-windata.h: Rename include guard.
* tui/tui-win.h: Rename include guard.
* tui/tui-stack.h: Rename include guard.
* tui/tui-source.h: Rename include guard.
* tui/tui-regs.h: Rename include guard.
* tui/tui-out.h: Rename include guard.
* tui/tui-layout.h: Rename include guard.
* tui/tui-io.h: Rename include guard.
* tui/tui-hooks.h: Rename include guard.
* tui/tui-file.h: Rename include guard.
* tui/tui-disasm.h: Rename include guard.
* tui/tui-data.h: Rename include guard.
* tui/tui-command.h: Rename include guard.
* tic6x-tdep.h: Add include guard.
* target/waitstatus.h: Rename include guard.
* target/wait.h: Rename include guard.
* target/target.h: Rename include guard.
* target/resume.h: Rename include guard.
* target-float.h: Rename include guard.
* stabsread.h: Add include guard.
* rs6000-tdep.h: Add include guard.
* riscv-fbsd-tdep.h: Add include guard.
* regformats/regdef.h: Rename include guard.
* record.h: Rename include guard.
* python/python.h: Rename include guard.
* python/python-internal.h: Rename include guard.
* python/py-stopevent.h: Rename include guard.
* python/py-ref.h: Rename include guard.
* python/py-record.h: Rename include guard.
* python/py-record-full.h: Rename include guard.
* python/py-record-btrace.h: Rename include guard.
* python/py-instruction.h: Rename include guard.
* python/py-events.h: Rename include guard.
* python/py-event.h: Rename include guard.
* procfs.h: Add include guard.
* proc-utils.h: Add include guard.
* p-lang.h: Add include guard.
* or1k-tdep.h: Rename include guard.
* observable.h: Rename include guard.
* nto-tdep.h: Rename include guard.
* nat/x86-linux.h: Rename include guard.
* nat/x86-linux-dregs.h: Rename include guard.
* nat/x86-gcc-cpuid.h: Add include guard.
* nat/x86-dregs.h: Rename include guard.
* nat/x86-cpuid.h: Rename include guard.
* nat/ppc-linux.h: Rename include guard.
* nat/mips-linux-watch.h: Rename include guard.
* nat/linux-waitpid.h: Rename include guard.
* nat/linux-ptrace.h: Rename include guard.
* nat/linux-procfs.h: Rename include guard.
* nat/linux-osdata.h: Rename include guard.
* nat/linux-nat.h: Rename include guard.
* nat/linux-namespaces.h: Rename include guard.
* nat/linux-btrace.h: Rename include guard.
* nat/glibc_thread_db.h: Rename include guard.
* nat/gdb_thread_db.h: Rename include guard.
* nat/gdb_ptrace.h: Rename include guard.
* nat/fork-inferior.h: Rename include guard.
* nat/amd64-linux-siginfo.h: Rename include guard.
* nat/aarch64-sve-linux-sigcontext.h: Rename include guard.
* nat/aarch64-sve-linux-ptrace.h: Rename include guard.
* nat/aarch64-linux.h: Rename include guard.
* nat/aarch64-linux-hw-point.h: Rename include guard.
* mn10300-tdep.h: Add include guard.
* mips-linux-tdep.h: Add include guard.
* mi/mi-parse.h: Rename include guard.
* mi/mi-out.h: Rename include guard.
* mi/mi-main.h: Rename include guard.
* mi/mi-interp.h: Rename include guard.
* mi/mi-getopt.h: Rename include guard.
* mi/mi-console.h: Rename include guard.
* mi/mi-common.h: Rename include guard.
* mi/mi-cmds.h: Rename include guard.
* mi/mi-cmd-break.h: Rename include guard.
* m2-lang.h: Add include guard.
* location.h: Rename include guard.
* linux-record.h: Rename include guard.
* linux-nat.h: Add include guard.
* linux-fork.h: Add include guard.
* i386-darwin-tdep.h: Rename include guard.
* hppa-linux-offsets.h: Add include guard.
* guile/guile.h: Rename include guard.
* guile/guile-internal.h: Rename include guard.
* gnu-nat.h: Rename include guard.
* gdb-stabs.h: Rename include guard.
* frv-tdep.h: Add include guard.
* f-lang.h: Add include guard.
* event-loop.h: Add include guard.
* darwin-nat.h: Rename include guard.
* cp-abi.h: Rename include guard.
* config/sparc/nm-sol2.h: Rename include guard.
* config/nm-nto.h: Rename include guard.
* config/nm-linux.h: Add include guard.
* config/i386/nm-i386gnu.h: Rename include guard.
* config/djgpp/nl_types.h: Rename include guard.
* config/djgpp/langinfo.h: Rename include guard.
* compile/gcc-cp-plugin.h: Add include guard.
* compile/gcc-c-plugin.h: Add include guard.
* compile/compile.h: Rename include guard.
* compile/compile-object-run.h: Rename include guard.
* compile/compile-object-load.h: Rename include guard.
* compile/compile-internal.h: Rename include guard.
* compile/compile-cplus.h: Rename include guard.
* compile/compile-c.h: Rename include guard.
* common/xml-utils.h: Rename include guard.
* common/x86-xstate.h: Rename include guard.
* common/version.h: Rename include guard.
* common/vec.h: Rename include guard.
* common/tdesc.h: Rename include guard.
* common/selftest.h: Rename include guard.
* common/scoped_restore.h: Rename include guard.
* common/scoped_mmap.h: Rename include guard.
* common/scoped_fd.h: Rename include guard.
* common/safe-iterator.h: Rename include guard.
* common/run-time-clock.h: Rename include guard.
* common/refcounted-object.h: Rename include guard.
* common/queue.h: Rename include guard.
* common/ptid.h: Rename include guard.
* common/print-utils.h: Rename include guard.
* common/preprocessor.h: Rename include guard.
* common/pathstuff.h: Rename include guard.
* common/observable.h: Rename include guard.
* common/netstuff.h: Rename include guard.
* common/job-control.h: Rename include guard.
* common/host-defs.h: Rename include guard.
* common/gdb_wait.h: Rename include guard.
* common/gdb_vecs.h: Rename include guard.
* common/gdb_unlinker.h: Rename include guard.
* common/gdb_unique_ptr.h: Rename include guard.
* common/gdb_tilde_expand.h: Rename include guard.
* common/gdb_sys_time.h: Rename include guard.
* common/gdb_string_view.h: Rename include guard.
* common/gdb_splay_tree.h: Rename include guard.
* common/gdb_setjmp.h: Rename include guard.
* common/gdb_ref_ptr.h: Rename include guard.
* common/gdb_optional.h: Rename include guard.
* common/gdb_locale.h: Rename include guard.
* common/gdb_assert.h: Rename include guard.
* common/filtered-iterator.h: Rename include guard.
* common/filestuff.h: Rename include guard.
* common/fileio.h: Rename include guard.
* common/environ.h: Rename include guard.
* common/common-utils.h: Rename include guard.
* common/common-types.h: Rename include guard.
* common/common-regcache.h: Rename include guard.
* common/common-inferior.h: Rename include guard.
* common/common-gdbthread.h: Rename include guard.
* common/common-exceptions.h: Rename include guard.
* common/common-defs.h: Rename include guard.
* common/common-debug.h: Rename include guard.
* common/cleanups.h: Rename include guard.
* common/buffer.h: Rename include guard.
* common/btrace-common.h: Rename include guard.
* common/break-common.h: Rename include guard.
* cli/cli-utils.h: Rename include guard.
* cli/cli-style.h: Rename include guard.
* cli/cli-setshow.h: Rename include guard.
* cli/cli-script.h: Rename include guard.
* cli/cli-interp.h: Rename include guard.
* cli/cli-decode.h: Rename include guard.
* cli/cli-cmds.h: Rename include guard.
* charset-list.h: Add include guard.
* buildsym-legacy.h: Rename include guard.
* bfin-tdep.h: Add include guard.
* ax.h: Rename include guard.
* arm-linux-tdep.h: Add include guard.
* arm-fbsd-tdep.h: Add include guard.
* arch/xtensa.h: Rename include guard.
* arch/tic6x.h: Add include guard.
* arch/i386.h: Add include guard.
* arch/arm.h: Rename include guard.
* arch/arm-linux.h: Rename include guard.
* arch/arm-get-next-pcs.h: Rename include guard.
* arch/amd64.h: Add include guard.
* arch/aarch64-insn.h: Rename include guard.
* arch-utils.h: Rename include guard.
* annotate.h: Add include guard.
* amd64-darwin-tdep.h: Rename include guard.
* aarch64-linux-tdep.h: Add include guard.
* aarch64-fbsd-tdep.h: Add include guard.
* aarch32-linux-nat.h: Add include guard.
gdb/gdbserver/ChangeLog
2019-02-07 Tom Tromey <tom@tromey.com>
* x86-tdesc.h: Rename include guard.
* x86-low.h: Add include guard.
* wincecompat.h: Rename include guard.
* win32-low.h: Add include guard.
* utils.h: Rename include guard.
* tracepoint.h: Rename include guard.
* tdesc.h: Rename include guard.
* target.h: Rename include guard.
* server.h: Rename include guard.
* remote-utils.h: Rename include guard.
* regcache.h: Rename include guard.
* nto-low.h: Rename include guard.
* notif.h: Add include guard.
* mem-break.h: Rename include guard.
* lynx-low.h: Add include guard.
* linux-x86-tdesc.h: Add include guard.
* linux-s390-tdesc.h: Add include guard.
* linux-ppc-tdesc-init.h: Add include guard.
* linux-low.h: Add include guard.
* linux-aarch64-tdesc.h: Add include guard.
* linux-aarch32-low.h: Add include guard.
* inferiors.h: Rename include guard.
* i387-fp.h: Rename include guard.
* hostio.h: Rename include guard.
* gdbthread.h: Rename include guard.
* gdb_proc_service.h: Rename include guard.
* event-loop.h: Rename include guard.
* dll.h: Rename include guard.
* debug.h: Rename include guard.
* ax.h: Rename include guard.
This commit applies all changes made after running the gdb/copyright.py
script.
Note that one file was flagged by the script, due to an invalid
copyright header
(gdb/unittests/basic_string_view/element_access/char/empty.cc).
As the file was copied from GCC's libstdc++-v3 testsuite, this commit
leaves this file untouched for the time being; a patch to fix the header
was sent to gcc-patches first.
gdb/ChangeLog:
Update copyright year range in all GDB files.
This turns gdbpy_ref into a template class, so that it can be used to
wrap subclasses of PyObject. The default argument remains PyObject;
and this necessitated renaming uses of "gdbpy_ref" to "gdbpy_ref<>".
gdb/ChangeLog
2017-02-10 Tom Tromey <tom@tromey.com>
* python/py-ref.h (gdbpy_ref_policy): Now a template.
(gdbpy_ref): Now a template; allow subclasses of PyObject to be
used.
* python/py-arch.c, python/py-bpevent.c, python/py-breakpoint.c,
python/py-cmd.c, python/py-continueevent.c, python/py-event.c,
python/py-exitedevent.c, python/py-finishbreakpoint.c,
python/py-framefilter.c, python/py-function.c,
python/py-inferior.c, python/py-infevents.c,
python/py-linetable.c, python/py-newobjfileevent.c,
python/py-param.c, python/py-prettyprint.c, python/py-ref.h,
python/py-signalevent.c, python/py-stopevent.c,
python/py-symbol.c, python/py-threadevent.c, python/py-type.c,
python/py-unwind.c, python/py-utils.c, python/py-value.c,
python/py-varobj.c, python/py-xmethods.c, python/python.c,
varobj.c: Change gdbpy_ref to gdbpy_ref<>.
This adds a new gdb_ref_ptr.h, that implements a reference-counting
smart pointer class, where the user of the class supplies a
reference-counting policy object.
This class will be used in the next patch, which changes most explicit
BFD reference counts to use this new type. Meanwhile, this patch
changes gdbpy_ref to be a specialization of this new class.
This change required adding new nullptr_t overloads some operators in
gdb_ref_ptr.h. I suspect this was needed because some Python header
redefines NULL, but I'm not certain.
2017-01-10 Tom Tromey <tom@tromey.com>
* common/gdb_ref_ptr.h: New file.
* python/py-ref.h (struct gdbpy_ref_policy): New.
(gdbpy_ref): Now a typedef.
This patch introduces class gdbpy_ref, which is a sort of smart
pointer that owns a single Python reference to a PyObject. This class
acts a bit like unique_ptr, but also a bit like shared_ptr (in that
copies do what you might expect); I considered going solely with
unique_ptr but it seemed quite strange to have a unique_ptr that
actually manages a shared resource.
Subsequent patches use this new class to simplify logic in the Python
layer.
2017-01-10 Tom Tromey <tom@tromey.com>
* python/py-ref.h: New file.
