What has changed in GDB?
(Organized release by release)
-*** Changes since GDB 6.6
+*** Changes since GDB 7.2
+
+* GDB has a new command: "thread find [REGEXP]".
+ It finds the thread id whose name, target id, or thread extra info
+ matches the given regular expression.
+
+* The "catch syscall" command now works on mips*-linux* targets.
+
+* The -data-disassemble MI command now supports modes 2 and 3 for
+ dumping the instruction opcodes.
+
+* New command line options
+
+-data-directory DIR Specify DIR as the "data-directory".
+ This is mostly for testing purposes.
+
+* The "maint set python auto-load on|off" command has been renamed to
+ "set auto-load-scripts on|off".
+
+* GDB has a new command: "set directories".
+ It is like the "dir" command except that it replaces the
+ source path list instead of augmenting it.
+
+* GDB now understands thread names.
+
+ On GNU/Linux, "info threads" will display the thread name as set by
+ prctl or pthread_setname_np.
+
+ There is also a new command, "thread name", which can be used to
+ assign a name internally for GDB to display.
+
+* OpenCL C
+ Initial support for the OpenCL C language (http://www.khronos.org/opencl)
+ has been integrated into GDB.
+
+* Python scripting
+
+ ** The function gdb.Write now accepts an optional keyword 'stream'.
+ This keyword, when provided, will direct the output to either
+ stdout, stderr, or GDB's logging output.
+
+ ** Parameters can now be be sub-classed in Python, and in particular
+ you may implement the get_set_doc and get_show_doc functions.
+ This improves how Parameter set/show documentation is processed
+ and allows for more dynamic content.
+
+ ** Symbols, Symbol Table, Symbol Table and Line, Object Files,
+ Inferior, Inferior Thread, Blocks, and Block Iterator APIs now
+ have an is_valid method.
+
+ ** Breakpoints can now be sub-classed in Python, and in particular
+ you may implement a 'stop' function that is executed each time
+ the inferior reaches that breakpoint.
+
+ ** New function gdb.lookup_global_symbol looks up a global symbol.
+
+ ** GDB values in Python are now callable if the value represents a
+ function. For example, if 'some_value' represents a function that
+ takes two integer parameters and returns a value, you can call
+ that function like so:
+
+ result = some_value (10,20)
+
+ ** Module gdb.types has been added.
+ It contains a collection of utilities for working with gdb.Types objects:
+ get_basic_type, has_field, make_enum_dict.
+
+ ** Module gdb.printing has been added.
+ It contains utilities for writing and registering pretty-printers.
+ New classes: PrettyPrinter, SubPrettyPrinter,
+ RegexpCollectionPrettyPrinter.
+ New function: register_pretty_printer.
+
+ ** New commands "info pretty-printers", "enable pretty-printer" and
+ "disable pretty-printer" have been added.
+
+ ** gdb.parameter("directories") is now available.
+
+ ** New function gdb.newest_frame returns the newest frame in the
+ selected thread.
+
+ ** The gdb.InferiorThread class has a new "name" attribute. This
+ holds the thread's name.
+
+ ** Python Support for Inferior events.
+ Python scripts can add observers to be notified of events
+ occurring in the process being debugged.
+ The following events are currently supported:
+ - gdb.events.cont Continue event.
+ - gdb.events.exited Inferior exited event.
+ - gdb.events.stop Signal received, and Breakpoint hit events.
+
+* C++ Improvements:
+
+ ** GDB now puts template parameters in scope when debugging in an
+ instantiation. For example, if you have:
+
+ template<int X> int func (void) { return X; }
+
+ then if you step into func<5>, "print X" will show "5". This
+ feature requires proper debuginfo support from the compiler; it
+ was added to GCC 4.5.
+
+ ** The motion commands "next", "finish", "until", and "advance" now
+ work better when exceptions are thrown. In particular, GDB will
+ no longer lose control of the inferior; instead, the GDB will
+ stop the inferior at the point at which the exception is caught.
+ This functionality requires a change in the exception handling
+ code that was introduced in GCC 4.5.
+
+* GDB now follows GCC's rules on accessing volatile objects when
+ reading or writing target state during expression evaluation.
+ One notable difference to prior behavior is that "print x = 0"
+ no longer generates a read of x; the value of the assignment is
+ now always taken directly from the value being assigned.
+
+* GDB now has some support for using labels in the program's source in
+ linespecs. For instance, you can use "advance label" to continue
+ execution to a label.
+
+* GDB now has support for reading and writing a new .gdb_index
+ section. This section holds a fast index of DWARF debugging
+ information and can be used to greatly speed up GDB startup and
+ operation. See the documentation for `save gdb-index' for details.
+
+* The "watch" command now accepts an optional "-location" argument.
+ When used, this causes GDB to watch the memory referred to by the
+ expression. Such a watchpoint is never deleted due to it going out
+ of scope.
+
+* GDB now supports thread debugging of core dumps on GNU/Linux.
+
+ GDB now activates thread debugging using the libthread_db library
+ when debugging GNU/Linux core dumps, similarly to when debugging
+ live processes. As a result, when debugging a core dump file, GDB
+ is now able to display pthread_t ids of threads. For example, "info
+ threads" shows the same output as when debugging the process when it
+ was live. In earlier releases, you'd see something like this:
+
+ (gdb) info threads
+ * 1 LWP 6780 main () at main.c:10
+
+ While now you see this:
+
+ (gdb) info threads
+ * 1 Thread 0x7f0f5712a700 (LWP 6780) main () at main.c:10
+
+ It is also now possible to inspect TLS variables when debugging core
+ dumps.
+
+ When debugging a core dump generated on a machine other than the one
+ used to run GDB, you may need to point GDB at the correct
+ libthread_db library with the "set libthread-db-search-path"
+ command. See the user manual for more details on this command.
+
+* When natively debugging programs on PowerPC BookE processors running
+ a Linux kernel version 2.6.34 or later, GDB supports ranged breakpoints,
+ which stop execution of the inferior whenever it executes an instruction
+ at any address within the specified range. See the "PowerPC Embedded"
+ section in the user manual for more details.
+
+* New features in the GDB remote stub, GDBserver
+
+ ** GDBserver is now supported on PowerPC LynxOS (versions 4.x and 5.x),
+ and i686 LynxOS (version 5.x).
+
+ ** GDBserver is now supported on Blackfin Linux.
+
+* New native configurations
+
+ia64 HP-UX ia64-*-hpux*
+
+* New targets:
+
+Analog Devices, Inc. Blackfin Processor bfin-*
+
+* Ada task switching is now supported on sparc-elf targets when
+ debugging a program using the Ravenscar Profile. For more information,
+ see the "Tasking Support when using the Ravenscar Profile" section
+ in the GDB user manual.
+
+* Guile support was removed.
+
+* New features in the GNU simulator
+
+ ** The --map-info flag lists all known core mappings.
+
+ ** CFI flashes may be simulated via the "cfi" device.
+
+*** Changes in GDB 7.2
+
+* Shared library support for remote targets by default
+
+ When GDB is configured for a generic, non-OS specific target, like
+ for example, --target=arm-eabi or one of the many *-*-elf targets,
+ GDB now queries remote stubs for loaded shared libraries using the
+ `qXfer:libraries:read' packet. Previously, shared library support
+ was always disabled for such configurations.
+
+* C++ Improvements:
+
+ ** Argument Dependent Lookup (ADL)
+
+ In C++ ADL lookup directs function search to the namespaces of its
+ arguments even if the namespace has not been imported.
+ For example:
+ namespace A
+ {
+ class B { };
+ void foo (B) { }
+ }
+ ...
+ A::B b
+ foo(b)
+ Here the compiler will search for `foo' in the namespace of 'b'
+ and find A::foo. GDB now supports this. This construct is commonly
+ used in the Standard Template Library for operators.
+
+ ** Improved User Defined Operator Support
+
+ In addition to member operators, GDB now supports lookup of operators
+ defined in a namespace and imported with a `using' directive, operators
+ defined in the global scope, operators imported implicitly from an
+ anonymous namespace, and the ADL operators mentioned in the previous
+ entry.
+ GDB now also supports proper overload resolution for all the previously
+ mentioned flavors of operators.
+
+ ** static const class members
+
+ Printing of static const class members that are initialized in the
+ class definition has been fixed.
+
+* Windows Thread Information Block access.
+
+ On Windows targets, GDB now supports displaying the Windows Thread
+ Information Block (TIB) structure. This structure is visible either
+ by using the new command `info w32 thread-information-block' or, by
+ dereferencing the new convenience variable named `$_tlb', a
+ thread-specific pointer to the TIB. This feature is also supported
+ when remote debugging using GDBserver.
+
+* Static tracepoints
+
+ Static tracepoints are calls in the user program into a tracing
+ library. One such library is a port of the LTTng kernel tracer to
+ userspace --- UST (LTTng Userspace Tracer, http://lttng.org/ust).
+ When debugging with GDBserver, GDB now supports combining the GDB
+ tracepoint machinery with such libraries. For example: the user can
+ use GDB to probe a static tracepoint marker (a call from the user
+ program into the tracing library) with the new "strace" command (see
+ "New commands" below). This creates a "static tracepoint" in the
+ breakpoint list, that can be manipulated with the same feature set
+ as fast and regular tracepoints. E.g., collect registers, local and
+ global variables, collect trace state variables, and define
+ tracepoint conditions. In addition, the user can collect extra
+ static tracepoint marker specific data, by collecting the new
+ $_sdata internal variable. When analyzing the trace buffer, you can
+ inspect $_sdata like any other variable available to GDB. For more
+ information, see the "Tracepoints" chapter in GDB user manual. New
+ remote packets have been defined to support static tracepoints, see
+ the "New remote packets" section below.
+
+* Better reconstruction of tracepoints after disconnected tracing
+
+ GDB will attempt to download the original source form of tracepoint
+ definitions when starting a trace run, and then will upload these
+ upon reconnection to the target, resulting in a more accurate
+ reconstruction of the tracepoints that are in use on the target.
+
+* Observer mode
+
+ You can now exercise direct control over the ways that GDB can
+ affect your program. For instance, you can disallow the setting of
+ breakpoints, so that the program can run continuously (assuming
+ non-stop mode). In addition, the "observer" variable is available
+ to switch all of the different controls; in observer mode, GDB
+ cannot affect the target's behavior at all, which is useful for
+ tasks like diagnosing live systems in the field.
+
+* The new convenience variable $_thread holds the number of the
+ current thread.
+
+* New remote packets
+
+qGetTIBAddr
+
+ Return the address of the Windows Thread Information Block of a given thread.
+
+qRelocInsn
+
+ In response to several of the tracepoint packets, the target may now
+ also respond with a number of intermediate `qRelocInsn' request
+ packets before the final result packet, to have GDB handle
+ relocating an instruction to execute at a different address. This
+ is particularly useful for stubs that support fast tracepoints. GDB
+ reports support for this feature in the qSupported packet.
+
+qTfSTM, qTsSTM
+
+ List static tracepoint markers in the target program.
+
+qTSTMat
+
+ List static tracepoint markers at a given address in the target
+ program.
+
+qXfer:statictrace:read
+
+ Read the static trace data collected (by a `collect $_sdata'
+ tracepoint action). The remote stub reports support for this packet
+ to gdb's qSupported query.
+
+QAllow
+
+ Send the current settings of GDB's permission flags.
+
+QTDPsrc
+
+ Send part of the source (textual) form of a tracepoint definition,
+ which includes location, conditional, and action list.
+
+* The source command now accepts a -s option to force searching for the
+ script in the source search path even if the script name specifies
+ a directory.
+
+* New features in the GDB remote stub, GDBserver
+
+ - GDBserver now support tracepoints (including fast tracepoints, and
+ static tracepoints). The feature is currently supported by the
+ i386-linux and amd64-linux builds. See the "Tracepoints support
+ in gdbserver" section in the manual for more information.
+
+ GDBserver JIT compiles the tracepoint's conditional agent
+ expression bytecode into native code whenever possible for low
+ overhead dynamic tracepoints conditionals. For such tracepoints,
+ an expression that examines program state is evaluated when the
+ tracepoint is reached, in order to determine whether to capture
+ trace data. If the condition is simple and false, processing the
+ tracepoint finishes very quickly and no data is gathered.
+
+ GDBserver interfaces with the UST (LTTng Userspace Tracer) library
+ for static tracepoints support.
+
+ - GDBserver now supports x86_64 Windows 64-bit debugging.
+
+* GDB now sends xmlRegisters= in qSupported packet to indicate that
+ it understands register description.
+
+* The --batch flag now disables pagination and queries.
+
+* X86 general purpose registers
+
+ GDB now supports reading/writing byte, word and double-word x86
+ general purpose registers directly. This means you can use, say,
+ $ah or $ax to refer, respectively, to the byte register AH and
+ 16-bit word register AX that are actually portions of the 32-bit
+ register EAX or 64-bit register RAX.
+
+* The `commands' command now accepts a range of breakpoints to modify.
+ A plain `commands' following a command that creates multiple
+ breakpoints affects all the breakpoints set by that command. This
+ applies to breakpoints set by `rbreak', and also applies when a
+ single `break' command creates multiple breakpoints (e.g.,
+ breakpoints on overloaded c++ functions).
+
+* The `rbreak' command now accepts a filename specification as part of
+ its argument, limiting the functions selected by the regex to those
+ in the specified file.
+
+* Support for remote debugging Windows and SymbianOS shared libraries
+ from Unix hosts has been improved. Non Windows GDB builds now can
+ understand target reported file names that follow MS-DOS based file
+ system semantics, such as file names that include drive letters and
+ use the backslash character as directory separator. This makes it
+ possible to transparently use the "set sysroot" and "set
+ solib-search-path" on Unix hosts to point as host copies of the
+ target's shared libraries. See the new command "set
+ target-file-system-kind" described below, and the "Commands to
+ specify files" section in the user manual for more information.
+
+* New commands
+
+eval template, expressions...
+ Convert the values of one or more expressions under the control
+ of the string template to a command line, and call it.
+
+set target-file-system-kind unix|dos-based|auto
+show target-file-system-kind
+ Set or show the assumed file system kind for target reported file
+ names.
+
+save breakpoints <filename>
+ Save all current breakpoint definitions to a file suitable for use
+ in a later debugging session. To read the saved breakpoint
+ definitions, use the `source' command.
+
+`save tracepoints' is a new alias for `save-tracepoints'. The latter
+is now deprecated.
+
+info static-tracepoint-markers
+ Display information about static tracepoint markers in the target.
+
+strace FN | FILE:LINE | *ADDR | -m MARKER_ID
+ Define a static tracepoint by probing a marker at the given
+ function, line, address, or marker ID.
+
+set observer on|off
+show observer
+ Enable and disable observer mode.
+
+set may-write-registers on|off
+set may-write-memory on|off
+set may-insert-breakpoints on|off
+set may-insert-tracepoints on|off
+set may-insert-fast-tracepoints on|off
+set may-interrupt on|off
+ Set individual permissions for GDB effects on the target. Note that
+ some of these settings can have undesirable or surprising
+ consequences, particularly when changed in the middle of a session.
+ For instance, disabling the writing of memory can prevent
+ breakpoints from being inserted, cause single-stepping to fail, or
+ even crash your program, if you disable after breakpoints have been
+ inserted. However, GDB should not crash.
+
+set record memory-query on|off
+show record memory-query
+ Control whether to stop the inferior if memory changes caused
+ by an instruction cannot be recorded.
+
+* Changed commands
+
+disassemble
+ The disassemble command now supports "start,+length" form of two arguments.
+
+* Python scripting
+
+** GDB now provides a new directory location, called the python directory,
+ where Python scripts written for GDB can be installed. The location
+ of that directory is <data-directory>/python, where <data-directory>
+ is the GDB data directory. For more details, see section `Scripting
+ GDB using Python' in the manual.
+
+** The GDB Python API now has access to breakpoints, symbols, symbol
+ tables, program spaces, inferiors, threads and frame's code blocks.
+ Additionally, GDB Parameters can now be created from the API, and
+ manipulated via set/show in the CLI.
+
+** New functions gdb.target_charset, gdb.target_wide_charset,
+ gdb.progspaces, gdb.current_progspace, and gdb.string_to_argv.
+
+** New exception gdb.GdbError.
+
+** Pretty-printers are now also looked up in the current program space.
+
+** Pretty-printers can now be individually enabled and disabled.
+
+** GDB now looks for names of Python scripts to auto-load in a
+ special section named `.debug_gdb_scripts', in addition to looking
+ for a OBJFILE-gdb.py script when OBJFILE is read by the debugger.
+
+* Tracepoint actions were unified with breakpoint commands. In particular,
+there are no longer differences in "info break" output for breakpoints and
+tracepoints and the "commands" command can be used for both tracepoints and
+regular breakpoints.
+
+* New targets
+
+ARM Symbian arm*-*-symbianelf*
+
+* D language support.
+ GDB now supports debugging programs written in the D programming
+ language.
+
+* GDB now supports the extended ptrace interface for PowerPC which is
+ available since Linux kernel version 2.6.34. This automatically enables
+ any hardware breakpoints and additional hardware watchpoints available in
+ the processor. The old ptrace interface exposes just one hardware
+ watchpoint and no hardware breakpoints.
+
+* GDB is now able to use the Data Value Compare (DVC) register available on
+ embedded PowerPC processors to implement in hardware simple watchpoint
+ conditions of the form:
+
+ watch ADDRESS|VARIABLE if ADDRESS|VARIABLE == CONSTANT EXPRESSION
+
+ This works in native GDB running on Linux kernels with the extended ptrace
+ interface mentioned above.
+
+*** Changes in GDB 7.1
+
+* C++ Improvements
+
+ ** Namespace Support
+
+ GDB now supports importing of namespaces in C++. This enables the
+ user to inspect variables from imported namespaces. Support for
+ namepace aliasing has also been added. So, if a namespace is
+ aliased in the current scope (e.g. namepace C=A; ) the user can
+ print variables using the alias (e.g. (gdb) print C::x).
+
+ ** Bug Fixes
+
+ All known bugs relating to the printing of virtual base class were
+ fixed. It is now possible to call overloaded static methods using a
+ qualified name.
+
+ ** Cast Operators
+
+ The C++ cast operators static_cast<>, dynamic_cast<>, const_cast<>,
+ and reinterpret_cast<> are now handled by the C++ expression parser.
+
+* New targets
+
+Xilinx MicroBlaze microblaze-*-*
+Renesas RX rx-*-elf
+
+* New Simulators
+
+Xilinx MicroBlaze microblaze
+Renesas RX rx
+
+* Multi-program debugging.
+
+ GDB now has support for multi-program (a.k.a. multi-executable or
+ multi-exec) debugging. This allows for debugging multiple inferiors
+ simultaneously each running a different program under the same GDB
+ session. See "Debugging Multiple Inferiors and Programs" in the
+ manual for more information. This implied some user visible changes
+ in the multi-inferior support. For example, "info inferiors" now
+ lists inferiors that are not running yet or that have exited
+ already. See also "New commands" and "New options" below.
+
+* New tracing features
+
+ GDB's tracepoint facility now includes several new features:
+
+ ** Trace state variables
+
+ GDB tracepoints now include support for trace state variables, which
+ are variables managed by the target agent during a tracing
+ experiment. They are useful for tracepoints that trigger each
+ other, so for instance one tracepoint can count hits in a variable,
+ and then a second tracepoint has a condition that is true when the
+ count reaches a particular value. Trace state variables share the
+ $-syntax of GDB convenience variables, and can appear in both
+ tracepoint actions and condition expressions. Use the "tvariable"
+ command to create, and "info tvariables" to view; see "Trace State
+ Variables" in the manual for more detail.
+
+ ** Fast tracepoints
+
+ GDB now includes an option for defining fast tracepoints, which
+ targets may implement more efficiently, such as by installing a jump
+ into the target agent rather than a trap instruction. The resulting
+ speedup can be by two orders of magnitude or more, although the
+ tradeoff is that some program locations on some target architectures
+ might not allow fast tracepoint installation, for instance if the
+ instruction to be replaced is shorter than the jump. To request a
+ fast tracepoint, use the "ftrace" command, with syntax identical to
+ the regular trace command.
+
+ ** Disconnected tracing
+
+ It is now possible to detach GDB from the target while it is running
+ a trace experiment, then reconnect later to see how the experiment
+ is going. In addition, a new variable disconnected-tracing lets you
+ tell the target agent whether to continue running a trace if the
+ connection is lost unexpectedly.
+
+ ** Trace files
+
+ GDB now has the ability to save the trace buffer into a file, and
+ then use that file as a target, similarly to you can do with
+ corefiles. You can select trace frames, print data that was
+ collected in them, and use tstatus to display the state of the
+ tracing run at the moment that it was saved. To create a trace
+ file, use "tsave <filename>", and to use it, do "target tfile
+ <name>".
+
+ ** Circular trace buffer
+
+ You can ask the target agent to handle the trace buffer as a
+ circular buffer, discarding the oldest trace frames to make room for
+ newer ones, by setting circular-trace-buffer to on. This feature may
+ not be available for all target agents.
+
+* Changed commands
+
+disassemble
+ The disassemble command, when invoked with two arguments, now requires
+ the arguments to be comma-separated.
+
+info variables
+ The info variables command now displays variable definitions. Files
+ which only declare a variable are not shown.
+
+source
+ The source command is now capable of sourcing Python scripts.
+ This feature is dependent on the debugger being build with Python
+ support.
+
+ Related to this enhancement is also the introduction of a new command
+ "set script-extension" (see below).
+
+* New commands (for set/show, see "New options" below)
+
+record save [<FILENAME>]
+ Save a file (in core file format) containing the process record
+ execution log for replay debugging at a later time.
+
+record restore <FILENAME>
+ Restore the process record execution log that was saved at an
+ earlier time, for replay debugging.
+
+add-inferior [-copies <N>] [-exec <FILENAME>]
+ Add a new inferior.
+
+clone-inferior [-copies <N>] [ID]
+ Make a new inferior ready to execute the same program another
+ inferior has loaded.
+
+remove-inferior ID
+ Remove an inferior.
+
+maint info program-spaces
+ List the program spaces loaded into GDB.
+
+set remote interrupt-sequence [Ctrl-C | BREAK | BREAK-g]
+show remote interrupt-sequence
+ Allow the user to select one of ^C, a BREAK signal or BREAK-g
+ as the sequence to the remote target in order to interrupt the execution.
+ Ctrl-C is a default. Some system prefers BREAK which is high level of
+ serial line for some certain time. Linux kernel prefers BREAK-g, a.k.a
+ Magic SysRq g. It is BREAK signal and character 'g'.
+
+set remote interrupt-on-connect [on | off]
+show remote interrupt-on-connect
+ When interrupt-on-connect is ON, gdb sends interrupt-sequence to
+ remote target when gdb connects to it. This is needed when you debug
+ Linux kernel.
+
+set remotebreak [on | off]
+show remotebreak
+Deprecated. Use "set/show remote interrupt-sequence" instead.
+
+tvariable $NAME [ = EXP ]
+ Create or modify a trace state variable.
+
+info tvariables
+ List trace state variables and their values.
+
+delete tvariable $NAME ...
+ Delete one or more trace state variables.
+
+teval EXPR, ...
+ Evaluate the given expressions without collecting anything into the
+ trace buffer. (Valid in tracepoint actions only.)
+
+ftrace FN / FILE:LINE / *ADDR
+ Define a fast tracepoint at the given function, line, or address.
+
+* New expression syntax
+
+ GDB now parses the 0b prefix of binary numbers the same way as GCC does.
+ GDB now parses 0b101010 identically with 42.
+
+* New options
+
+set follow-exec-mode new|same
+show follow-exec-mode
+ Control whether GDB reuses the same inferior across an exec call or
+ creates a new one. This is useful to be able to restart the old
+ executable after the inferior having done an exec call.
+
+set default-collect EXPR, ...
+show default-collect
+ Define a list of expressions to be collected at each tracepoint.
+ This is a useful way to ensure essential items are not overlooked,
+ such as registers or a critical global variable.
+
+set disconnected-tracing
+show disconnected-tracing
+ If set to 1, the target is instructed to continue tracing if it
+ loses its connection to GDB. If 0, the target is to stop tracing
+ upon disconnection.
+
+set circular-trace-buffer
+show circular-trace-buffer
+ If set to on, the target is instructed to use a circular trace buffer
+ and discard the oldest trace frames instead of stopping the trace due
+ to a full trace buffer. If set to off, the trace stops when the buffer
+ fills up. Some targets may not support this.
+
+set script-extension off|soft|strict
+show script-extension
+ If set to "off", the debugger does not perform any script language
+ recognition, and all sourced files are assumed to be GDB scripts.
+ If set to "soft" (the default), files are sourced according to
+ filename extension, falling back to GDB scripts if the first
+ evaluation failed.
+ If set to "strict", files are sourced according to filename extension.
+
+set ada trust-PAD-over-XVS on|off
+show ada trust-PAD-over-XVS
+ If off, activate a workaround against a bug in the debugging information
+ generated by the compiler for PAD types (see gcc/exp_dbug.ads in
+ the GCC sources for more information about the GNAT encoding and
+ PAD types in particular). It is always safe to set this option to
+ off, but this introduces a slight performance penalty. The default
+ is on.
+
+* Python API Improvements
+
+ ** GDB provides the new class gdb.LazyString. This is useful in
+ some pretty-printing cases. The new method gdb.Value.lazy_string
+ provides a simple way to create objects of this type.
+
+ ** The fields returned by gdb.Type.fields now have an
+ `is_base_class' attribute.
+
+ ** The new method gdb.Type.range returns the range of an array type.
+
+ ** The new method gdb.parse_and_eval can be used to parse and
+ evaluate an expression.
+
+* New remote packets
+
+QTDV
+ Define a trace state variable.
+
+qTV
+ Get the current value of a trace state variable.
+
+QTDisconnected
+ Set desired tracing behavior upon disconnection.
+
+QTBuffer:circular
+ Set the trace buffer to be linear or circular.
+
+qTfP, qTsP
+ Get data about the tracepoints currently in use.
+
+* Bug fixes
+
+Process record now works correctly with hardware watchpoints.
+
+Multiple bug fixes have been made to the mips-irix port, making it
+much more reliable. In particular:
+ - Debugging threaded applications is now possible again. Previously,
+ GDB would hang while starting the program, or while waiting for
+ the program to stop at a breakpoint.
+ - Attaching to a running process no longer hangs.
+ - An error occurring while loading a core file has been fixed.
+ - Changing the value of the PC register now works again. This fixes
+ problems observed when using the "jump" command, or when calling
+ a function from GDB, or even when assigning a new value to $pc.
+ - With the "finish" and "return" commands, the return value for functions
+ returning a small array is now correctly printed.
+ - It is now possible to break on shared library code which gets executed
+ during a shared library init phase (code executed while executing
+ their .init section). Previously, the breakpoint would have no effect.
+ - GDB is now able to backtrace through the signal handler for
+ non-threaded programs.
+
+PIE (Position Independent Executable) programs debugging is now supported.
+This includes debugging execution of PIC (Position Independent Code) shared
+libraries although for that, it should be possible to run such libraries as an
+executable program.
+
+*** Changes in GDB 7.0
+
+* GDB now has an interface for JIT compilation. Applications that
+dynamically generate code can create symbol files in memory and register
+them with GDB. For users, the feature should work transparently, and
+for JIT developers, the interface is documented in the GDB manual in the
+"JIT Compilation Interface" chapter.
+
+* Tracepoints may now be conditional. The syntax is as for
+breakpoints; either an "if" clause appended to the "trace" command,
+or the "condition" command is available. GDB sends the condition to
+the target for evaluation using the same bytecode format as is used
+for tracepoint actions.
+
+* The disassemble command now supports: an optional /r modifier, print the
+raw instructions in hex as well as in symbolic form, and an optional /m
+modifier to print mixed source+assembly.
+
+* Process record and replay
+
+ In a architecture environment that supports ``process record and
+ replay'', ``process record and replay'' target can record a log of
+ the process execution, and replay it with both forward and reverse
+ execute commands.
+
+* Reverse debugging: GDB now has new commands reverse-continue, reverse-
+step, reverse-next, reverse-finish, reverse-stepi, reverse-nexti, and
+set execution-direction {forward|reverse}, for targets that support
+reverse execution.
+
+* GDB now supports hardware watchpoints on MIPS/Linux systems. This
+feature is available with a native GDB running on kernel version
+2.6.28 or later.
+
+* GDB now has support for multi-byte and wide character sets on the
+target. Strings whose character type is wchar_t, char16_t, or
+char32_t are now correctly printed. GDB supports wide- and unicode-
+literals in C, that is, L'x', L"string", u'x', u"string", U'x', and
+U"string" syntax. And, GDB allows the "%ls" and "%lc" formats in
+`printf'. This feature requires iconv to work properly; if your
+system does not have a working iconv, GDB can use GNU libiconv. See
+the installation instructions for more information.
+
+* GDB now supports automatic retrieval of shared library files from
+remote targets. To use this feature, specify a system root that begins
+with the `remote:' prefix, either via the `set sysroot' command or via
+the `--with-sysroot' configure-time option.
+
+* "info sharedlibrary" now takes an optional regex of libraries to show,
+and it now reports if a shared library has no debugging information.
+
+* Commands `set debug-file-directory', `set solib-search-path' and `set args'
+now complete on file names.
+
+* When completing in expressions, gdb will attempt to limit
+completions to allowable structure or union fields, where appropriate.
+For instance, consider:
+
+ # struct example { int f1; double f2; };
+ # struct example variable;
+ (gdb) p variable.
+
+If the user types TAB at the end of this command line, the available
+completions will be "f1" and "f2".
+
+* Inlined functions are now supported. They show up in backtraces, and
+the "step", "next", and "finish" commands handle them automatically.
+
+* GDB now supports the token-splicing (##) and stringification (#)
+operators when expanding macros. It also supports variable-arity
+macros.
+
+* GDB now supports inspecting extra signal information, exported by
+the new $_siginfo convenience variable. The feature is currently
+implemented on linux ARM, i386 and amd64.
+
+* GDB can now display the VFP floating point registers and NEON vector
+registers on ARM targets. Both ARM GNU/Linux native GDB and gdbserver
+can provide these registers (requires Linux 2.6.30 or later). Remote
+and simulator targets may also provide them.
+
+* New remote packets
+
+qSearch:memory:
+ Search memory for a sequence of bytes.
+
+QStartNoAckMode
+ Turn off `+'/`-' protocol acknowledgments to permit more efficient
+ operation over reliable transport links. Use of this packet is
+ controlled by the `set remote noack-packet' command.
+
+vKill
+ Kill the process with the specified process ID. Use this in preference
+ to `k' when multiprocess protocol extensions are supported.
+
+qXfer:osdata:read
+ Obtains additional operating system information
+
+qXfer:siginfo:read
+qXfer:siginfo:write
+ Read or write additional signal information.
+
+* Removed remote protocol undocumented extension
+
+ An undocumented extension to the remote protocol's `S' stop reply
+ packet that permited the stub to pass a process id was removed.
+ Remote servers should use the `T' stop reply packet instead.
+
+* GDB now supports multiple function calling conventions according to the
+DWARF-2 DW_AT_calling_convention function attribute.
+
+* The SH target utilizes the aforementioned change to distinguish between gcc
+and Renesas calling convention. It also adds the new CLI commands
+`set/show sh calling-convention'.
+
+* GDB can now read compressed debug sections, as produced by GNU gold
+with the --compress-debug-sections=zlib flag.
+
+* 64-bit core files are now supported on AIX.
+
+* Thread switching is now supported on Tru64.
+
+* Watchpoints can now be set on unreadable memory locations, e.g. addresses
+which will be allocated using malloc later in program execution.
+
+* The qXfer:libraries:read remote procotol packet now allows passing a
+list of section offsets.
+
+* On GNU/Linux, GDB can now attach to stopped processes. Several race
+conditions handling signals delivered during attach or thread creation
+have also been fixed.
+
+* GDB now supports the use of DWARF boolean types for Ada's type Boolean.
+From the user's standpoint, all unqualified instances of True and False
+are treated as the standard definitions, regardless of context.
+
+* GDB now parses C++ symbol and type names more flexibly. For
+example, given:
+
+ template<typename T> class C { };
+ C<char const *> c;
+
+GDB will now correctly handle all of:
+
+ ptype C<char const *>
+ ptype C<char const*>
+ ptype C<const char *>
+ ptype C<const char*>
+
+* New features in the GDB remote stub, gdbserver
+
+ - The "--wrapper" command-line argument tells gdbserver to use a
+ wrapper program to launch programs for debugging.
+
+ - On PowerPC and S/390 targets, it is now possible to use a single
+ gdbserver executable to debug both 32-bit and 64-bit programs.
+ (This requires gdbserver itself to be built as a 64-bit executable.)
+
+ - gdbserver uses the new noack protocol mode for TCP connections to
+ reduce communications latency, if also supported and enabled in GDB.
+
+ - Support for the sparc64-linux-gnu target is now included in
+ gdbserver.
+
+ - The amd64-linux build of gdbserver now supports debugging both
+ 32-bit and 64-bit programs.
+
+ - The i386-linux, amd64-linux, and i386-win32 builds of gdbserver
+ now support hardware watchpoints, and will use them automatically
+ as appropriate.
+
+* Python scripting
+
+ GDB now has support for scripting using Python. Whether this is
+ available is determined at configure time.
+
+ New GDB commands can now be written in Python.
+
+* Ada tasking support
+
+ Ada tasks can now be inspected in GDB. The following commands have
+ been introduced:
+
+ info tasks
+ Print the list of Ada tasks.
+ info task N
+ Print detailed information about task number N.
+ task
+ Print the task number of the current task.
+ task N
+ Switch the context of debugging to task number N.
+
+* Support for user-defined prefixed commands. The "define" command can
+add new commands to existing prefixes, e.g. "target".
+
+* Multi-inferior, multi-process debugging.
+
+ GDB now has generalized support for multi-inferior debugging. See
+ "Debugging Multiple Inferiors" in the manual for more information.
+ Although availability still depends on target support, the command
+ set is more uniform now. The GNU/Linux specific multi-forks support
+ has been migrated to this new framework. This implied some user
+ visible changes; see "New commands" and also "Removed commands"
+ below.
+
+* Target descriptions can now describe the target OS ABI. See the
+"Target Description Format" section in the user manual for more
+information.
+
+* Target descriptions can now describe "compatible" architectures
+to indicate that the target can execute applications for a different
+architecture in addition to those for the main target architecture.
+See the "Target Description Format" section in the user manual for
+more information.
+
+* Multi-architecture debugging.
+
+ GDB now includes general supports for debugging applications on
+ hybrid systems that use more than one single processor architecture
+ at the same time. Each such hybrid architecture still requires
+ specific support to be added. The only hybrid architecture supported
+ in this version of GDB is the Cell Broadband Engine.
+
+* GDB now supports integrated debugging of Cell/B.E. applications that
+use both the PPU and SPU architectures. To enable support for hybrid
+Cell/B.E. debugging, you need to configure GDB to support both the
+powerpc-linux or powerpc64-linux and the spu-elf targets, using the
+--enable-targets configure option.
+
+* Non-stop mode debugging.
+
+ For some targets, GDB now supports an optional mode of operation in
+ which you can examine stopped threads while other threads continue
+ to execute freely. This is referred to as non-stop mode, with the
+ old mode referred to as all-stop mode. See the "Non-Stop Mode"
+ section in the user manual for more information.
+
+ To be able to support remote non-stop debugging, a remote stub needs
+ to implement the non-stop mode remote protocol extensions, as
+ described in the "Remote Non-Stop" section of the user manual. The
+ GDB remote stub, gdbserver, has been adjusted to support these
+ extensions on linux targets.
+
+* New commands (for set/show, see "New options" below)
+
+catch syscall [NAME(S) | NUMBER(S)]
+ Catch system calls. Arguments, which should be names of system
+ calls or their numbers, mean catch only those syscalls. Without
+ arguments, every syscall will be caught. When the inferior issues
+ any of the specified syscalls, GDB will stop and announce the system
+ call, both when it is called and when its call returns. This
+ feature is currently available with a native GDB running on the
+ Linux Kernel, under the following architectures: x86, x86_64,
+ PowerPC and PowerPC64.
+
+find [/size-char] [/max-count] start-address, end-address|+search-space-size,
+ val1 [, val2, ...]
+ Search memory for a sequence of bytes.
+
+maint set python print-stack
+maint show python print-stack
+ Show a stack trace when an error is encountered in a Python script.
+
+python [CODE]
+ Invoke CODE by passing it to the Python interpreter.
+
+macro define
+macro list
+macro undef
+ These allow macros to be defined, undefined, and listed
+ interactively.
+
+info os processes
+ Show operating system information about processes.
+
+info inferiors
+ List the inferiors currently under GDB's control.
+
+inferior NUM
+ Switch focus to inferior number NUM.
+
+detach inferior NUM
+ Detach from inferior number NUM.
+
+kill inferior NUM
+ Kill inferior number NUM.
+
+* New options
+
+set spu stop-on-load
+show spu stop-on-load
+ Control whether to stop for new SPE threads during Cell/B.E. debugging.
+
+set spu auto-flush-cache
+show spu auto-flush-cache
+ Control whether to automatically flush the software-managed cache
+ during Cell/B.E. debugging.
+
+set sh calling-convention
+show sh calling-convention
+ Control the calling convention used when calling SH target functions.
+
+set debug timestamp
+show debug timestamp
+ Control display of timestamps with GDB debugging output.
+
+set disassemble-next-line
+show disassemble-next-line
+ Control display of disassembled source lines or instructions when
+ the debuggee stops.
+
+set remote noack-packet
+show remote noack-packet
+ Set/show the use of remote protocol QStartNoAckMode packet. See above
+ under "New remote packets."
+
+set remote query-attached-packet
+show remote query-attached-packet
+ Control use of remote protocol `qAttached' (query-attached) packet.
+
+set remote read-siginfo-object
+show remote read-siginfo-object
+ Control use of remote protocol `qXfer:siginfo:read' (read-siginfo-object)
+ packet.
+
+set remote write-siginfo-object
+show remote write-siginfo-object
+ Control use of remote protocol `qXfer:siginfo:write' (write-siginfo-object)
+ packet.
+
+set remote reverse-continue
+show remote reverse-continue
+ Control use of remote protocol 'bc' (reverse-continue) packet.
+
+set remote reverse-step
+show remote reverse-step
+ Control use of remote protocol 'bs' (reverse-step) packet.
+
+set displaced-stepping
+show displaced-stepping
+ Control displaced stepping mode. Displaced stepping is a way to
+ single-step over breakpoints without removing them from the debuggee.
+ Also known as "out-of-line single-stepping".
+
+set debug displaced
+show debug displaced
+ Control display of debugging info for displaced stepping.
+
+maint set internal-error
+maint show internal-error
+ Control what GDB does when an internal error is detected.
+
+maint set internal-warning
+maint show internal-warning
+ Control what GDB does when an internal warning is detected.
+
+set exec-wrapper
+show exec-wrapper
+unset exec-wrapper
+ Use a wrapper program to launch programs for debugging.
+
+set multiple-symbols (all|ask|cancel)
+show multiple-symbols
+ The value of this variable can be changed to adjust the debugger behavior
+ when an expression or a breakpoint location contains an ambiguous symbol
+ name (an overloaded function name, for instance).
+
+set breakpoint always-inserted
+show breakpoint always-inserted
+ Keep breakpoints always inserted in the target, as opposed to inserting
+ them when resuming the target, and removing them when the target stops.
+ This option can improve debugger performance on slow remote targets.
+
+set arm fallback-mode (arm|thumb|auto)
+show arm fallback-mode
+set arm force-mode (arm|thumb|auto)
+show arm force-mode
+ These commands control how ARM GDB determines whether instructions
+ are ARM or Thumb. The default for both settings is auto, which uses
+ the current CPSR value for instructions without symbols; previous
+ versions of GDB behaved as if "set arm fallback-mode arm".
+
+set disable-randomization
+show disable-randomization
+ Standalone programs run with the virtual address space randomization enabled
+ by default on some platforms. This option keeps the addresses stable across
+ multiple debugging sessions.
+
+set non-stop
+show non-stop
+ Control whether other threads are stopped or not when some thread hits
+ a breakpoint.
+
+set target-async
+show target-async
+ Requests that asynchronous execution is enabled in the target, if available.
+ In this case, it's possible to resume target in the background, and interact
+ with GDB while the target is running. "show target-async" displays the
+ current state of asynchronous execution of the target.
+
+set target-wide-charset
+show target-wide-charset
+ The target-wide-charset is the name of the character set that GDB
+ uses when printing characters whose type is wchar_t.
+
+set tcp auto-retry (on|off)
+show tcp auto-retry
+set tcp connect-timeout
+show tcp connect-timeout
+ These commands allow GDB to retry failed TCP connections to a remote stub
+ with a specified timeout period; this is useful if the stub is launched
+ in parallel with GDB but may not be ready to accept connections immediately.
+
+set libthread-db-search-path
+show libthread-db-search-path
+ Control list of directories which GDB will search for appropriate
+ libthread_db.
+
+set schedule-multiple (on|off)
+show schedule-multiple
+ Allow GDB to resume all threads of all processes or only threads of
+ the current process.
+
+set stack-cache
+show stack-cache
+ Use more aggressive caching for accesses to the stack. This improves
+ performance of remote debugging (particularly backtraces) without
+ affecting correctness.
+
+set interactive-mode (on|off|auto)
+show interactive-mode
+ Control whether GDB runs in interactive mode (on) or not (off).
+ When in interactive mode, GDB waits for the user to answer all
+ queries. Otherwise, GDB does not wait and assumes the default
+ answer. When set to auto (the default), GDB determines which
+ mode to use based on the stdin settings.
+
+* Removed commands
+
+info forks
+ For program forks, this is replaced by the new more generic `info
+ inferiors' command. To list checkpoints, you can still use the
+ `info checkpoints' command, which was an alias for the `info forks'
+ command.
+
+fork NUM
+ Replaced by the new `inferior' command. To switch between
+ checkpoints, you can still use the `restart' command, which was an
+ alias for the `fork' command.
+
+process PID
+ This is removed, since some targets don't have a notion of
+ processes. To switch between processes, you can still use the
+ `inferior' command using GDB's own inferior number.
+
+delete fork NUM
+ For program forks, this is replaced by the new more generic `kill
+ inferior' command. To delete a checkpoint, you can still use the
+ `delete checkpoint' command, which was an alias for the `delete
+ fork' command.
+
+detach fork NUM
+ For program forks, this is replaced by the new more generic `detach
+ inferior' command. To detach a checkpoint, you can still use the
+ `detach checkpoint' command, which was an alias for the `detach
+ fork' command.
+
+* New native configurations
+
+x86/x86_64 Darwin i[34567]86-*-darwin*
+
+x86_64 MinGW x86_64-*-mingw*
+
+* New targets
+
+Lattice Mico32 lm32-*
+x86 DICOS i[34567]86-*-dicos*
+x86_64 DICOS x86_64-*-dicos*
+S+core 3 score-*-*
+
+* The GDB remote stub, gdbserver, now supports x86 Windows CE
+ (mingw32ce) debugging.
+
+* Removed commands
+
+catch load
+catch unload
+ These commands were actually not implemented on any target.
+
+*** Changes in GDB 6.8
+
+* New native configurations
+
+NetBSD/hppa hppa*-*netbsd*
+Xtensa GNU/Linux xtensa*-*-linux*
+
+* New targets
+
+NetBSD/hppa hppa*-*-netbsd*
+Xtensa GNU/Lunux xtensa*-*-linux*
+
+* Change in command line behavior -- corefiles vs. process ids.
+
+ When the '-p NUMBER' or '--pid NUMBER' options are used, and
+ attaching to process NUMBER fails, GDB no longer attempts to open a
+ core file named NUMBER. Attaching to a program using the -c option
+ is no longer supported. Instead, use the '-p' or '--pid' options.
+
+* GDB can now be built as a native debugger for debugging Windows x86
+(mingw32) Portable Executable (PE) programs.
+
+* Pending breakpoints no longer change their number when their address
+is resolved.
+
+* GDB now supports breakpoints with multiple locations,
+including breakpoints on C++ constructors, inside C++ templates,
+and in inlined functions.
+
+* GDB's ability to debug optimized code has been improved. GDB more
+accurately identifies function bodies and lexical blocks that occupy
+more than one contiguous range of addresses.
+
+* Target descriptions can now describe registers for PowerPC.
+
+* The GDB remote stub, gdbserver, now supports the AltiVec and SPE
+registers on PowerPC targets.
+
+* The GDB remote stub, gdbserver, now supports thread debugging on GNU/Linux
+targets even when the libthread_db library is not available.
+
+* The GDB remote stub, gdbserver, now supports the new file transfer
+commands (remote put, remote get, and remote delete).
+
+* The GDB remote stub, gdbserver, now supports run and attach in
+extended-remote mode.
+
+* hppa*64*-*-hpux11* target broken
+The debugger is unable to start a program and fails with the following
+error: "Error trying to get information about dynamic linker".
+The gdb-6.7 release is also affected.
+
+* GDB now supports the --enable-targets= configure option to allow
+building a single GDB executable that supports multiple remote
+target architectures.
+
+* GDB now supports debugging C and C++ programs which use the
+Decimal Floating Point extension. In addition, the PowerPC target
+now has a set of pseudo-registers to inspect decimal float values
+stored in two consecutive float registers.
+
+* The -break-insert MI command can optionally create pending
+breakpoints now.
+
+* Improved support for debugging Ada
+Many improvements to the Ada language support have been made. These
+include:
+ - Better support for Ada2005 interface types
+ - Improved handling of arrays and slices in general
+ - Better support for Taft-amendment types
+ - The '{type} ADDRESS' expression is now allowed on the left hand-side
+ of an assignment
+ - Improved command completion in Ada
+ - Several bug fixes
+
+* GDB on GNU/Linux and HP/UX can now debug through "exec" of a new
+process.
+
+* New commands
+
+set print frame-arguments (all|scalars|none)
+show print frame-arguments
+ The value of this variable can be changed to control which argument
+ values should be printed by the debugger when displaying a frame.
+
+remote put
+remote get
+remote delete
+ Transfer files to and from a remote target, and delete remote files.
+
+* New MI commands
+
+-target-file-put
+-target-file-get
+-target-file-delete
+ Transfer files to and from a remote target, and delete remote files.
+
+* New remote packets
+
+vFile:open:
+vFile:close:
+vFile:pread:
+vFile:pwrite:
+vFile:unlink:
+ Open, close, read, write, and delete files on the remote system.
+
+vAttach
+ Attach to an existing process on the remote system, in extended-remote
+ mode.
+
+vRun
+ Run a new process on the remote system, in extended-remote mode.
+
+*** Changes in GDB 6.7
+
+* Resolved 101 resource leaks, null pointer dereferences, etc. in gdb,
+bfd, libiberty and opcodes, as revealed by static analysis donated by
+Coverity, Inc. (http://scan.coverity.com).
* When looking up multiply-defined global symbols, GDB will now prefer the
symbol definition in the current shared library if it was built using the
target's overall architecture. GDB can read a description from
a local file or over the remote serial protocol.
-* Arrays of explicitly SIGNED or UNSIGNED CHARs are now printed as arrays
-of numbers.
+* Vectors of single-byte data use a new integer type which is not
+automatically displayed as character or string data.
+
+* The /s format now works with the print command. It displays
+arrays of single-byte integers and pointers to single-byte integers
+as strings.
* Target descriptions can now describe target-specific registers,
for architectures which have implemented the support (currently
-only ARM and MIPS).
+only ARM, M68K, and MIPS).
* GDB and the GDB remote stub, gdbserver, now support the XScale
iWMMXt coprocessor.
* The GDB remote stub, gdbserver, now supports dynamic link libraries
(DLLs) on Windows and Windows CE targets.
+* GDB now supports a faster verification that a .debug file matches its binary
+according to its build-id signature, if the signature is present.
+
* New commands
set remoteflow
projects / deliverable / binutils-gdb.git / blobdiff