What has changed in GDB?
(Organized release by release)
-*** Changes since GDB 10
+*** Changes since GDB 12
+
+* GDB now supports dumping memory tag data for AArch64 MTE. It also supports
+ reading memory tag data for AArch64 MTE from core files generated by
+ the gcore command or the Linux kernel.
+
+ When a process uses memory-mapped pages protected by memory tags (for
+ example, AArch64 MTE), this additional information will be recorded in
+ the core file in the event of a crash or if GDB generates a core file
+ from the current process state. GDB will show this additional information
+ automatically, or through one of the memory-tag subcommands.
+
+* "info breakpoints" now displays enabled breakpoint locations of
+ disabled breakpoints as in the "y-" state. For example:
+
+ (gdb) info breakpoints
+ Num Type Disp Enb Address What
+ 1 breakpoint keep n <MULTIPLE>
+ 1.1 y- 0x00000000000011b6 in ...
+ 1.2 y- 0x00000000000011c2 in ...
+ 1.3 n 0x00000000000011ce in ...
+
+* Support for Thread Local Storage (TLS) variables on FreeBSD arm and
+ aarch64 architectures.
+
+* GDB now supports hardware watchpoints on FreeBSD/Aarch64.
+
+* Remove support for building against Python 2, it is now only possible to
+ build GDB against Python 3.
+
+* DBX mode has been removed.
+
+* GDB now honours the DWARF prologue_end line-table entry flag the compiler can
+ emit to indicate where a breakpoint should be placed to break in a function
+ past its prologue.
+
+* Completion now also offers "NUMBER" for "set" commands that accept
+ a numeric argument and the "unlimited" keyword. For example:
+
+ (gdb) set width <TAB>
+ NUMBER unlimited
+
+ and consequently:
+
+ (gdb) complete set width
+ set width NUMBER
+ set width unlimited
+
+* Disassembler styling using libopcodes. GDB now supports
+ disassembler styling using libopcodes. This is only available for
+ some targets (currently x86 and RISC-V). For unsupported targets
+ Python Pygments is still used. For supported targets, libopcodes
+ styling is used by default.
+
+* The Windows native target now supports target async.
+
+* New commands
+
+maintenance set ignore-prologue-end-flag on|off
+maintenance show ignore-prologue-end-flag
+ This setting, which is off by default, controls whether GDB ignores the
+ PROLOGUE-END flag from the line-table when skipping prologue. This can be
+ used to force GDB to use prologue analyzers if the line-table is constructed
+ from erroneous debug information.
+
+set print nibbles [on|off]
+show print nibbles
+ This controls whether the 'print/t' command will display binary values
+ in groups of four bits, known as "nibbles". The default is 'off'.
+
+maintenance set libopcodes-styling on|off
+maintenance show libopcodes-styling
+ These can be used to force off libopcodes based styling, the Python
+ Pygments styling will then be used instead.
+
+set style disassembler comment
+show style disassembler comment
+set style disassembler immediate
+show style disassembler immediate
+set style disassembler mnemonic
+show style disassembler mnemonic
+set style disassembler register
+show style disassembler register
+set style disassembler address
+show style disassembler address
+set style disassembler symbol
+show style disassembler symbol
+ For targets that support libopcodes based styling, these settings
+ control how various aspects of the disassembler output are styled.
+ The 'disassembler address' and 'disassembler symbol' styles are
+ aliases for the 'address' and 'function' styles respectively.
+
+maintenance print frame-id [ LEVEL ]
+ Print GDB's internal frame-id for the frame at LEVEL. If LEVEL is
+ not given, then print the frame-id for the currently selected frame.
+
+* Changed commands
+
+document user-defined
+ It is now possible to document user-defined aliases.
+ When a user-defined alias is documented, the help and apropos commands
+ use the provided documentation instead of the documentation of the
+ aliased command.
+ Documenting a user-defined alias is particularly useful when the alias
+ is a set of nested 'with' commands to avoid showing the help of
+ the with command for an alias that will in fact launch the
+ last command given in the nested commands.
+
+maintenance info line-table
+ Add a PROLOGUE-END column to the output which indicates that an
+ entry corresponds to an address where a breakpoint should be placed
+ to be at the first instruction past a function's prologue.
+
+* New targets
+
+GNU/Linux/LoongArch (gdbserver) loongarch*-*-linux*
+
+GNU/Linux/CSKY (gdbserver) csky*-*linux*
+
+* Python API
+
+ ** GDB will now reformat the doc string for gdb.Command and
+ gdb.Parameter sub-classes to remove unnecessary leading
+ whitespace from each line before using the string as the help
+ output.
+
+ ** New function gdb.format_address(ADDRESS, PROGSPACE, ARCHITECTURE),
+ that formats ADDRESS as 'address <symbol+offset>', where symbol is
+ looked up in PROGSPACE, and ARCHITECTURE is used to format address.
+ This is the same format that GDB uses when printing address, symbol,
+ and offset information from the disassembler.
+
+ ** New function gdb.current_language that returns the name of the
+ current language. Unlike gdb.parameter('language'), this will
+ never return 'auto'.
+
+ ** New method gdb.Frame.language that returns the name of the
+ frame's language.
+
+ ** New Python API for wrapping GDB's disassembler:
+
+ - gdb.disassembler.register_disassembler(DISASSEMBLER, ARCH).
+ DISASSEMBLER is a sub-class of gdb.disassembler.Disassembler.
+ ARCH is either None or a string containing a bfd architecture
+ name. DISASSEMBLER is registered as a disassembler for
+ architecture ARCH, or for all architectures if ARCH is None.
+ The previous disassembler registered for ARCH is returned, this
+ can be None if no previous disassembler was registered.
+
+ - gdb.disassembler.Disassembler is the class from which all
+ disassemblers should inherit. Its constructor takes a string,
+ a name for the disassembler, which is currently only used in
+ some debug output. Sub-classes should override the __call__
+ method to perform disassembly, invoking __call__ on this base
+ class will raise an exception.
+
+ - gdb.disassembler.DisassembleInfo is the class used to describe
+ a single disassembly request from GDB. An instance of this
+ class is passed to the __call__ method of
+ gdb.disassembler.Disassembler and has the following read-only
+ attributes: 'address', and 'architecture', as well as the
+ following method: 'read_memory'.
+
+ - gdb.disassembler.builtin_disassemble(INFO, MEMORY_SOURCE),
+ calls GDB's builtin disassembler on INFO, which is a
+ gdb.disassembler.DisassembleInfo object. MEMORY_SOURCE is
+ optional, its default value is None. If MEMORY_SOURCE is not
+ None then it must be an object that has a 'read_memory' method.
+
+ - gdb.disassembler.DisassemblerResult is a class that can be used
+ to wrap the result of a call to a Disassembler. It has
+ read-only attributes 'length' and 'string'.
+
+ ** gdb.Objfile now has an attribute named "is_file". This is True
+ if the objfile comes from a file, and False otherwise.
+
+ ** New function gdb.print_options that returns a dictionary of the
+ prevailing print options, in the form accepted by
+ gdb.Value.format_string.
+
+ ** gdb.Value.format_string now uses the format provided by 'print',
+ if it is called during a 'print' or other similar operation.
+
+ ** gdb.Value.format_string now accepts the 'summary' keyword. This
+ can be used to request a shorter representation of a value, the
+ way that 'set print frame-arguments scalars' does.
+
+ ** New Python type gdb.BreakpointLocation.
+ The new attribute 'locations' of gdb.Breakpoint returns a list of
+ gdb.BreakpointLocation objects specifying the locations where the
+ breakpoint is inserted into the debuggee.
+
+* New features in the GDB remote stub, GDBserver
+
+ ** GDBserver is now supported on LoongArch GNU/Linux.
+
+ ** GDBserver is now supported on CSKY GNU/Linux.
+
+* LoongArch floating-point support
+
+GDB now supports floating-point on LoongArch GNU/Linux.
+
+*** Changes in GDB 12
+
+* DBX mode is deprecated, and will be removed in GDB 13
+
+* GDB 12 is the last release of GDB that will support building against
+ Python 2. From GDB 13, it will only be possible to build GDB itself
+ with Python 3 support.
+
+* The disable-randomization setting now works on Windows.
+
+* Improved C++ template support
+
+ GDB now treats functions/types involving C++ templates like it does function
+ overloads. Users may omit parameter lists to set breakpoints on families of
+ template functions, including types/functions composed of multiple template types:
+
+ (gdb) break template_func(template_1, int)
+
+ The above will set breakpoints at every function `template_func' where
+ the first function parameter is any template type named `template_1' and
+ the second function parameter is `int'.
+
+ TAB completion also gains similar improvements.
+
+* The FreeBSD native target now supports async mode.
+
+* Configure changes
+
+--enable-threading
+
+ Enable or disable multithreaded symbol loading. This is enabled
+ by default, but passing --disable-threading or --enable-threading=no
+ to configure will disable it.
+
+ Disabling this can cause a performance penalty when there are a lot of
+ symbols to load, but is useful for debugging purposes.
+
+* New commands
+
+maint set backtrace-on-fatal-signal on|off
+maint show backtrace-on-fatal-signal
+ This setting is 'on' by default. When 'on' GDB will print a limited
+ backtrace to stderr in the situation where GDB terminates with a
+ fatal signal. This only supported on some platforms where the
+ backtrace and backtrace_symbols_fd functions are available.
+
+set source open on|off
+show source open
+ This setting, which is on by default, controls whether GDB will try
+ to open source code files. Switching this off will stop GDB trying
+ to open and read source code files, which can be useful if the files
+ are located over a slow network connection.
+
+set varsize-limit
+show varsize-limit
+ These are now deprecated aliases for "set max-value-size" and
+ "show max-value-size".
+
+task apply [all | TASK-IDS...] [FLAG]... COMMAND
+ Like "thread apply", but applies COMMAND to Ada tasks.
+
+watch [...] task ID
+ Watchpoints can now be restricted to a specific Ada task.
+
+maint set internal-error backtrace on|off
+maint show internal-error backtrace
+maint set internal-warning backtrace on|off
+maint show internal-warning backtrace
+ GDB can now print a backtrace of itself when it encounters either an
+ internal-error, or an internal-warning. This is on by default for
+ internal-error and off by default for internal-warning.
+
+set logging on|off
+ Deprecated and replaced by "set logging enabled on|off".
+
+set logging enabled on|off
+show logging enabled
+ These commands set or show whether logging is enabled or disabled.
+
+exit
+ You can now exit GDB by using the new command "exit", in addition to
+ the existing "quit" command.
+
+set debug threads on|off
+show debug threads
+ Print additional debug messages about thread creation and deletion.
+
+set debug linux-nat on|off
+show debug linux-nat
+ These new commands replaced the old 'set debug lin-lwp' and 'show
+ debug lin-lwp' respectively. Turning this setting on prints debug
+ messages relating to GDB's handling of native Linux inferiors.
+
+maint flush source-cache
+ Flush the contents of the source code cache.
+
+maint set gnu-source-highlight enabled on|off
+maint show gnu-source-highlight enabled
+ Whether GDB should use the GNU Source Highlight library for adding
+ styling to source code. When off, the library will not be used, even
+ when available. When GNU Source Highlight isn't used, or can't add
+ styling to a particular source file, then the Python Pygments
+ library will be used instead.
+
+set suppress-cli-notifications (on|off)
+show suppress-cli-notifications
+ This controls whether printing the notifications is suppressed for CLI.
+ CLI notifications occur when you change the selected context
+ (i.e., the current inferior, thread and/or the frame), or when
+ the program being debugged stops (e.g., because of hitting a
+ breakpoint, completing source-stepping, an interrupt, etc.).
+
+set style disassembler enabled on|off
+show style disassembler enabled
+ If GDB is compiled with Python support, and the Python Pygments
+ package is available, then, when this setting is on, disassembler
+ output will have styling applied.
+
+set ada source-charset
+show ada source-charset
+ Set the character set encoding that is assumed for Ada symbols. Valid
+ values for this follow the values that can be passed to the GNAT
+ compiler via the '-gnati' option. The default is ISO-8859-1.
+
+tui layout
+tui focus
+tui refresh
+tui window height
+ These are the new names for the old 'layout', 'focus', 'refresh',
+ and 'winheight' tui commands respectively. The old names still
+ exist as aliases to these new commands.
+
+tui window width
+winwidth
+ The new command 'tui window width', and the alias 'winwidth' allow
+ the width of a tui window to be adjusted when windows are laid out
+ in horizontal mode.
+
+set debug tui on|off
+show debug tui
+ Control the display of debug output about GDB's tui.
+
+* Changed commands
+
+print
+ Printing of floating-point values with base-modifying formats like
+ /x has been changed to display the underlying bytes of the value in
+ the desired base. This was GDB's documented behavior, but was never
+ implemented correctly.
+
+maint packet
+ This command can now print a reply, if the reply includes
+ non-printable characters. Any non-printable characters are printed
+ as escaped hex, e.g. \x?? where '??' is replaces with the value of
+ the non-printable character.
+
+clone-inferior
+ The clone-inferior command now ensures that the TTY, CMD and ARGS
+ settings are copied from the original inferior to the new one.
+ All modifications to the environment variables done using the 'set
+ environment' or 'unset environment' commands are also copied to the new
+ inferior.
+
+set debug lin-lwp on|off
+show debug lin-lwp
+ These commands have been removed from GDB. The new command 'set
+ debug linux-nat' and 'show debug linux-nat' should be used
+ instead.
+
+info win
+ This command now includes information about the width of the tui
+ windows in its output.
+
+layout
+focus
+refresh
+winheight
+ These commands are now aliases for the 'tui layout', 'tui focus',
+ 'tui refresh', and 'tui window height' commands respectively.
+
+* GDB's Ada parser now supports an extension for specifying the exact
+ byte contents of a floating-point literal. This can be useful for
+ setting floating-point registers to a precise value without loss of
+ precision. The syntax is an extension of the based literal syntax.
+ Use, e.g., "16lf#0123abcd#" -- the number of "l"s controls the width
+ of the floating-point type, and the "f" is the marker for floating
+ point.
+
+* MI changes
+
+ ** The '-add-inferior' with no option flags now inherits the
+ connection of the current inferior, this restores the behaviour of
+ GDB as it was prior to GDB 10.
+
+ ** The '-add-inferior' command now accepts a '--no-connection'
+ option, which causes the new inferior to start without a
+ connection.
+
+ ** The default version of the MI interpreter is now 4 (-i=mi4).
+
+ ** The "script" field in breakpoint output (which is syntactically
+ incorrect in MI 3 and below) has changed in MI 4 to become a list.
+ This affects the following commands and events:
+
+ - -break-insert
+ - -break-info
+ - =breakpoint-created
+ - =breakpoint-modified
+
+ The -fix-breakpoint-script-output command can be used to enable
+ this behavior with previous MI versions.
+
+* New targets
+
+GNU/Linux/LoongArch loongarch*-*-linux*
+
+* Removed targets
+
+S+core score-*-*
+
+* Python API
+
+ ** New function gdb.add_history(), which takes a gdb.Value object
+ and adds the value it represents to GDB's history list. An
+ integer, the index of the new item in the history list, is
+ returned.
+
+ ** New function gdb.history_count(), which returns the number of
+ values in GDB's value history.
+
+ ** New gdb.events.gdb_exiting event. This event is called with a
+ gdb.GdbExitingEvent object which has the read-only attribute
+ 'exit_code', which contains the value of the GDB exit code. This
+ event is triggered once GDB decides it is going to exit, but
+ before GDB starts to clean up its internal state.
+
+ ** New function gdb.architecture_names(), which returns a list
+ containing all of the possible Architecture.name() values. Each
+ entry is a string.
+
+ ** New function gdb.Architecture.integer_type(), which returns an
+ integer type given a size and a signed-ness.
+
+ ** New gdb.TargetConnection object type that represents a connection
+ (as displayed by the 'info connections' command). A sub-class,
+ gdb.RemoteTargetConnection, is used to represent 'remote' and
+ 'extended-remote' connections.
+
+ ** The gdb.Inferior type now has a 'connection' property which is an
+ instance of gdb.TargetConnection, the connection used by this
+ inferior. This can be None if the inferior has no connection.
+
+ ** New 'gdb.events.connection_removed' event registry, which emits a
+ 'gdb.ConnectionEvent' when a connection is removed from GDB.
+ This event has a 'connection' property, a gdb.TargetConnection
+ object for the connection being removed.
+
+ ** New gdb.connections() function that returns a list of all
+ currently active connections.
+
+ ** New gdb.RemoteTargetConnection.send_packet(PACKET) method. This
+ is equivalent to the existing 'maint packet' CLI command; it
+ allows a user specified packet to be sent to the remote target.
+
+ ** New function gdb.host_charset(), returns a string, which is the
+ name of the current host charset.
+
+ ** New gdb.set_parameter(NAME, VALUE). This sets the gdb parameter
+ NAME to VALUE.
+
+ ** New gdb.with_parameter(NAME, VALUE). This returns a context
+ manager that temporarily sets the gdb parameter NAME to VALUE,
+ then resets it when the context is exited.
+
+ ** The gdb.Value.format_string method now takes a 'styling'
+ argument, which is a boolean. When true, the returned string can
+ include escape sequences to apply styling. The styling will only
+ be present if styling is otherwise turned on in GDB (see 'help
+ set styling'). When false, which is the default if the argument
+ is not given, then no styling is applied to the returned string.
+
+ ** New read-only attribute gdb.InferiorThread.details, which is
+ either a string, containing additional, target specific thread
+ state information, or None, if there is no such additional
+ information.
+
+ ** New read-only attribute gdb.Type.is_scalar, which is True for
+ scalar types, and False for all other types.
+
+ ** New read-only attribute gdb.Type.is_signed. This attribute
+ should only be read when Type.is_scalar is True, and will be True
+ for signed types, and False for all other types. Attempting to
+ read this attribute for non-scalar types will raise a ValueError.
+
+ ** It is now possible to add GDB/MI commands implemented in Python.
+
+* New features in the GDB remote stub, GDBserver
+
+ ** GDBserver is now supported on OpenRISC GNU/Linux.
+
+* New native configurations
+
+GNU/Linux/OpenRISC or1k*-*-linux*
+
+*** Changes in GDB 11
+
+* The 'set disassembler-options' command now supports specifying options
+ for the ARC target.
* GDB now supports general memory tagging functionality if the underlying
architecture supports the proper primitives and hooks. Currently this is
equivalent of the CLI's "break -qualified" and "dprintf
-qualified".
+ ** '-break-insert --force-condition' and '-dprintf-insert --force-condition'
+
+ The MI -break-insert and -dprintf-insert commands now support a
+ '--force-condition' flag to forcibly define a condition even when
+ the condition is invalid at all locations of the breakpoint. This
+ is equivalent to the '-force-condition' flag of the CLI's "break"
+ command.
+
+ ** '-break-condition --force'
+
+ The MI -break-condition command now supports a '--force' flag to
+ forcibly define a condition even when the condition is invalid at
+ all locations of the selected breakpoint. This is equivalent to
+ the '-force' flag of the CLI's "cond" command.
+
+ ** '-file-list-exec-source-files [--group-by-objfile]
+ [--basename | --dirname]
+ [--] [REGEXP]'
+
+ The existing -file-list-exec-source-files command now takes an
+ optional REGEXP which is used to filter the source files that are
+ included in the results.
+
+ By default REGEXP is matched against the full filename of the
+ source file. When one of --basename or --dirname is given then
+ REGEXP is only matched against the specified part of the full
+ source filename.
+
+ When the optional --group-by-objfile flag is used the output
+ format is changed, the results are now a list of object files
+ (executable and libraries) with the source files that are
+ associated with each object file.
+
+ The results from -file-list-exec-source-files now include a
+ 'debug-fully-read' field which takes the value 'true' or 'false'.
+ A 'true' value indicates the source file is from a compilation
+ unit that has had its debug information fully read in by GDB, a
+ value of 'false' indicates GDB has only performed a partial scan
+ of the debug information so far.
+
* GDB now supports core file debugging for x86_64 Cygwin programs.
* GDB will now look for the .gdbinit file in a config directory before
and "-eiex" that allow options (that would normally appear in a
gdbearlyinit file) to be passed on the command line.
+* For RISC-V targets, the target feature "org.gnu.gdb.riscv.vector" is
+ now understood by GDB, and can be used to describe the vector
+ registers of a target. The precise requirements of this register
+ feature are documented in the GDB manual.
+
+* For ARM targets, the "org.gnu.gdb.arm.m-profile-mve" feature is now
+ supported by GDB and describes a new VPR register from the ARM MVE
+ (Helium) extension. See the GDB manual for more information.
+
+* TUI improvements
+
+ ** TUI windows now support mouse actions. The mouse wheel scrolls
+ the appropriate window.
+
+ ** Key combinations that do not have a specific action on the
+ focused window are passed to GDB. For example, you now can use
+ Ctrl-Left/Ctrl-Right to move between words in the command window
+ regardless of which window is in focus. Previously you would
+ need to focus on the command window for such key combinations to
+ work.
+
* New commands
set debug event-loop
maintenance info target-sections
Print GDB's internal target sections table.
+maintenance info jit
+ Print the JIT code objects in the inferior known to GDB.
+
memory-tag show-logical-tag POINTER
Print the logical tag for POINTER.
memory-tag with-logical-tag POINTER TAG
When 'on', the 'ptype' command uses hexadecimal notation to print sizes
and offsets of struct members. When 'off', decimal notation is used.
+set python ignore-environment on|off
+show python ignore-environment
+ When 'on', this causes GDB's builtin Python to ignore any
+ environment variables that would otherwise affect how Python
+ behaves. This command needs to be added to an early initialization
+ file (e.g. ~/.config/gdb/gdbearlyinit) in order to affect GDB.
+
+set python dont-write-bytecode auto|on|off
+show python dont-write-bytecode
+ When 'on', this causes GDB's builtin Python to not write any
+ byte-code (.pyc files) to disk. This command needs to be added to
+ an early initialization file (e.g. ~/.config/gdb/gdbearlyinit) in
+ order to affect GDB. When 'off' byte-code will always be written.
+ When set to 'auto' (the default) Python will check the
+ PYTHONDONTWRITEBYTECODE environment variable.
+
* Changed commands
break [PROBE_MODIFIER] [LOCATION] [thread THREADNUM]
offsets of struct members. Default behavior is given by 'show print
type hex'.
+info sources
+ The info sources command output has been restructured. The results
+ are now based around a list of objfiles (executable and libraries),
+ and for each objfile the source files that are part of that objfile
+ are listed.
+
* Removed targets and native configurations
ARM Symbian arm*-*-symbianelf*
Request the remote to store the specified allocation tags to the requested
memory range.
+* Guile API
+
+ ** Improved support for rvalue reference values:
+ TYPE_CODE_RVALUE_REF is now exported as part of the API and the
+ value-referenced-value procedure now handles rvalue reference
+ values.
+
+ ** New procedures for obtaining value variants:
+ value-reference-value, value-rvalue-reference-value and
+ value-const-value.
+
+ ** Temporary breakpoints can now be created with make-breakpoint and
+ tested for using breakpoint-temporary?.
+
+* Python API
+
+ ** Inferior objects now contain a read-only 'connection_num' attribute that
+ gives the connection number as seen in 'info connections' and
+ 'info inferiors'.
+
+ ** New method gdb.Frame.level() which returns the stack level of the
+ frame object.
+
+ ** New method gdb.PendingFrame.level() which returns the stack level
+ of the frame object.
+
+ ** When hitting a catchpoint, the Python API will now emit a
+ gdb.BreakpointEvent rather than a gdb.StopEvent. The
+ gdb.Breakpoint attached to the event will have type BP_CATCHPOINT.
+
+ ** Python TUI windows can now receive mouse click events. If the
+ Window object implements the click method, it is called for each
+ mouse click event in this window.
+
*** Changes in GDB 10
* There are new feature names for ARC targets: "org.gnu.gdb.arc.core"
GNU/Linux/RISC-V (gdbserver) riscv*-*-linux*
BPF bpf-unknown-none
+Z80 z80-unknown-*
* Python API
the current CPSR value for instructions without symbols; previous
versions of GDB behaved as if "set arm fallback-mode arm".
+set arm unwind-secure-frames
+ Enable unwinding from Non-secure to Secure mode on Cortex-M with
+ Security extension.
+ This can trigger security exceptions when unwinding exception stacks.
+
set disable-randomization
show disable-randomization
Standalone programs run with the virtual address space randomization enabled
projects / binutils-gdb.git / blobdiff