What has changed in GDB?
(Organized release by release)
-*** Changes since GDB 6.8
+*** Changes since GDB 7.0
+
+* 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.
+
+* 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.
+
+* 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.
+
+* 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.
+
+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.
+
+*** 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
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.
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
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
projects / deliverable / binutils-gdb.git / blobdiff