What has changed in GDB?
(Organized release by release)
-*** Changes since GDB 7.0
+*** Changes since GDB 7.1
+
+* 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.
+
+* Python scripting
+
+** The GDB Python API now has access to symbols, symbol tables, and
+ frame's code blocks.
+
+** New methods gdb.target_charset and gdb.target_wide_charset.
+
+* 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*
+
+*** 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
lists inferiors that are not running yet or that have exited
already. See also "New commands" and "New options" below.
-* Trace state variables
+* 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
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 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>]
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
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
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
for tracepoint actions.
* "disassemble" command with a /r modifier, print the raw instructions
-in hex as well as in symbolic form."
+in hex as well as in symbolic form.
* Process record and replay
projects / deliverable / binutils-gdb.git / blobdiff