What has changed in GDB?
(Organized release by release)
-*** Changes since GDB 7.9
-=======
+*** Changes since GDB 7.11
+
+* Intel MPX bound violation handling.
+
+ Segmentation faults caused by a Intel MPX boundary violation
+ now display the kind of violation (upper or lower), the memory
+ address accessed and the memory bounds, along with the usual
+ signal received and code location.
+
+ For example:
+
+ Program received signal SIGSEGV, Segmentation fault
+ Upper bound violation while accessing address 0x7fffffffc3b3
+ Bounds: [lower = 0x7fffffffc390, upper = 0x7fffffffc3a3]
+ 0x0000000000400d7c in upper () at i386-mpx-sigsegv.c:68
+
+*** Changes in GDB 7.11
+
+* GDB now supports debugging kernel-based threads on FreeBSD.
+
+* Per-inferior thread numbers
+
+ Thread numbers are now per inferior instead of global. If you're
+ debugging multiple inferiors, GDB displays thread IDs using a
+ qualified INF_NUM.THR_NUM form. For example:
+
+ (gdb) info threads
+ Id Target Id Frame
+ 1.1 Thread 0x7ffff7fc2740 (LWP 8155) (running)
+ 1.2 Thread 0x7ffff7fc1700 (LWP 8168) (running)
+ * 2.1 Thread 0x7ffff7fc2740 (LWP 8157) (running)
+ 2.2 Thread 0x7ffff7fc1700 (LWP 8190) (running)
+
+ As consequence, thread numbers as visible in the $_thread
+ convenience variable and in Python's InferiorThread.num attribute
+ are no longer unique between inferiors.
+
+ GDB now maintains a second thread ID per thread, referred to as the
+ global thread ID, which is the new equivalent of thread numbers in
+ previous releases. See also $_gthread below.
+
+ For backwards compatibility, MI's thread IDs always refer to global
+ IDs.
+
+* Commands that accept thread IDs now accept the qualified
+ INF_NUM.THR_NUM form as well. For example:
+
+ (gdb) thread 2.1
+ [Switching to thread 2.1 (Thread 0x7ffff7fc2740 (LWP 8157))] (running)
+ (gdb)
+
+* In commands that accept a list of thread IDs, you can now refer to
+ all threads of an inferior using a star wildcard. GDB accepts
+ "INF_NUM.*", to refer to all threads of inferior INF_NUM, and "*" to
+ refer to all threads of the current inferior. For example, "info
+ threads 2.*".
+
+* You can use "info threads -gid" to display the global thread ID of
+ all threads.
+
+* The new convenience variable $_gthread holds the global number of
+ the current thread.
+
+* The new convenience variable $_inferior holds the number of the
+ current inferior.
+
+* GDB now displays the ID and name of the thread that hit a breakpoint
+ or received a signal, if your program is multi-threaded. For
+ example:
+
+ Thread 3 "bar" hit Breakpoint 1 at 0x40087a: file program.c, line 20.
+ Thread 1 "main" received signal SIGINT, Interrupt.
+
+* Record btrace now supports non-stop mode.
+
+* Support for tracepoints on aarch64-linux was added in GDBserver.
+
+* The 'record instruction-history' command now indicates speculative execution
+ when using the Intel Processor Trace recording format.
+
+* GDB now allows users to specify explicit locations, bypassing
+ the linespec parser. This feature is also available to GDB/MI
+ clients.
+
+* Multi-architecture debugging is supported on AArch64 GNU/Linux.
+ GDB now is able to debug both AArch64 applications and ARM applications
+ at the same time.
+
+* Support for fast tracepoints on aarch64-linux was added in GDBserver,
+ including JIT compiling fast tracepoint's conditional expression bytecode
+ into native code.
+
+* GDB now supports displaced stepping on AArch64 GNU/Linux.
+
+* "info threads", "info inferiors", "info display", "info checkpoints"
+ and "maint info program-spaces" now list the corresponding items in
+ ascending ID order, for consistency with all other "info" commands.
+
+* In Ada, the overloads selection menu has been enhanced to display the
+ parameter types and the return types for the matching overloaded subprograms.
+
+* New commands
+
+maint set target-non-stop (on|off|auto)
+maint show target-non-stop
+ Control whether GDB targets always operate in non-stop mode even if
+ "set non-stop" is "off". The default is "auto", meaning non-stop
+ mode is enabled if supported by the target.
+
+maint set bfd-sharing
+maint show bfd-sharing
+ Control the reuse of bfd objects.
+
+set debug bfd-cache
+show debug bfd-cache
+ Control display of debugging info regarding bfd caching.
+
+set debug fbsd-lwp
+show debug fbsd-lwp
+ Control display of debugging info regarding FreeBSD threads.
+
+set remote multiprocess-extensions-packet
+show remote multiprocess-extensions-packet
+ Set/show the use of the remote protocol multiprocess extensions.
+
+set remote thread-events
+show remote thread-events
+ Set/show the use of thread create/exit events.
+
+set ada print-signatures on|off
+show ada print-signatures"
+ Control whether parameter types and return types are displayed in overloads
+ selection menus. It is activaled (@code{on}) by default.
+
+set max-value-size
+show max-value-size
+ Controls the maximum size of memory, in bytes, that GDB will
+ allocate for value contents. Prevents incorrect programs from
+ causing GDB to allocate overly large buffers. Default is 64k.
+
+skip -file file
+skip -gfile file-glob-pattern
+skip -function function
+skip -rfunction regular-expression
+ A generalized form of the skip command, with new support for
+ glob-style file names and regular expressions for function names.
+ Additionally, a file spec and a function spec may now be combined.
+
+* The "disassemble" command accepts a new modifier: /s.
+ It prints mixed source+disassembly like /m with two differences:
+ - disassembled instructions are now printed in program order, and
+ - and source for all relevant files is now printed.
+ The "/m" option is now considered deprecated: its "source-centric"
+ output hasn't proved useful in practice.
+
+* The "record instruction-history" command accepts a new modifier: /s.
+ It behaves exactly like /m and prints mixed source+disassembly.
+
+* The "set scheduler-locking" command supports a new mode "replay".
+ It behaves like "off" in record mode and like "on" in replay mode.
+
+* Support for various ROM monitors has been removed:
+
+ target dbug dBUG ROM monitor for Motorola ColdFire
+ target picobug Motorola picobug monitor
+ target dink32 DINK32 ROM monitor for PowerPC
+ target m32r Renesas M32R/D ROM monitor
+ target mon2000 mon2000 ROM monitor
+ target ppcbug PPCBUG ROM monitor for PowerPC
+
+* Support for reading/writing memory and extracting values on architectures
+ whose memory is addressable in units of any integral multiple of 8 bits.
+
+* New remote packets
+
+exec stop reason
+ Indicates that an exec system call was executed.
+
+exec-events feature in qSupported
+ The qSupported packet allows GDB to request support for exec
+ events using the new 'gdbfeature' exec-event, and the qSupported
+ response can contain the corresponding 'stubfeature'. Set and
+ show commands can be used to display whether these features are enabled.
+
+vCtrlC
+ Equivalent to interrupting with the ^C character, but works in
+ non-stop mode.
+
+thread created stop reason (T05 create:...)
+ Indicates that the thread was just created and is stopped at entry.
+
+thread exit stop reply (w exitcode;tid)
+ Indicates that the thread has terminated.
+
+QThreadEvents
+ Enables/disables thread create and exit event reporting. For
+ example, this is used in non-stop mode when GDB stops a set of
+ threads and synchronously waits for the their corresponding stop
+ replies. Without exit events, if one of the threads exits, GDB
+ would hang forever not knowing that it should no longer expect a
+ stop for that same thread.
+
+N stop reply
+
+ Indicates that there are no resumed threads left in the target (all
+ threads are stopped). The remote stub reports support for this stop
+ reply to GDB's qSupported query.
+
+QCatchSyscalls:1 [;SYSNO]...
+QCatchSyscalls:0
+ Enable ("QCatchSyscalls:1") or disable ("QCatchSyscalls:0")
+ catching syscalls from the inferior process.
+
+syscall_entry stop reason
+ Indicates that a syscall was just called.
+
+syscall_return stop reason
+ Indicates that a syscall just returned.
+
+QCatchSyscalls:1 in qSupported
+ The qSupported packet may now include QCatchSyscalls:1 in the reply
+ to indicate support for catching syscalls.
+
+* Extended-remote exec events
+
+ ** GDB now has support for exec events on extended-remote Linux targets.
+ For such targets with Linux kernels 2.5.46 and later, this enables
+ follow-exec-mode and exec catchpoints.
+
+set remote exec-event-feature-packet
+show remote exec-event-feature-packet
+ Set/show the use of the remote exec event feature.
+
+ * Thread names in remote protocol
+
+ The reply to qXfer:threads:read may now include a name attribute for each
+ thread.
+
+* Target remote mode fork and exec events
+
+ ** GDB now has support for fork and exec events on target remote mode
+ Linux targets. For such targets with Linux kernels 2.5.46 and later,
+ this enables follow-fork-mode, detach-on-fork, follow-exec-mode, and
+ fork and exec catchpoints.
+
+* Remote syscall events
+
+ ** GDB now has support for catch syscall on remote Linux targets,
+ currently enabled on x86/x86_64 architectures.
+
+set remote catch-syscall-packet
+show remote catch-syscall-packet
+ Set/show the use of the remote catch syscall feature.
+
+* MI changes
+
+ ** The -var-set-format command now accepts the zero-hexadecimal
+ format. It outputs data in hexadecimal format with zero-padding on the
+ left.
+
+* Python Scripting
+
+ ** gdb.InferiorThread objects have a new attribute "global_num",
+ which refers to the thread's global thread ID. The existing
+ "num" attribute now refers to the thread's per-inferior number.
+ See "Per-inferior thread numbers" above.
+ ** gdb.InferiorThread objects have a new attribute "inferior", which
+ is the Inferior object the thread belongs to.
+
+*** Changes in GDB 7.10
+
+* Support for process record-replay and reverse debugging on aarch64*-linux*
+ targets has been added. GDB now supports recording of A64 instruction set
+ including advance SIMD instructions.
+
+* Support for Sun's version of the "stabs" debug file format has been removed.
* GDB now honors the content of the file /proc/PID/coredump_filter
(PID is the process ID) on GNU/Linux systems. This file can be used
present in the debug info. This typically includes the compiler version
and may include things like its command line arguments.
+* The "info dll", an alias of the "info sharedlibrary" command,
+ is now available on all platforms.
+
* Directory names supplied to the "set sysroot" commands may be
prefixed with "target:" to tell GDB to access shared libraries from
the target system, be it local or remote. This replaces the prefix
* The "dump" command now supports verilog hex format.
+* GDB now supports the vector ABI on S/390 GNU/Linux targets.
+
+* On GNU/Linux, GDB and gdbserver are now able to access executable
+ and shared library files without a "set sysroot" command when
+ attaching to processes running in different mount namespaces from
+ the debugger. This makes it possible to attach to processes in
+ containers as simply as "gdb -p PID" or "gdbserver --attach PID".
+ See "New remote packets" below.
+
+* The "tui reg" command now provides completion for all of the
+ available register groups, including target specific groups.
+
+* The HISTSIZE environment variable is no longer read when determining
+ the size of GDB's command history. GDB now instead reads the dedicated
+ GDBHISTSIZE environment variable. Setting GDBHISTSIZE to "-1" or to "" now
+ disables truncation of command history. Non-numeric values of GDBHISTSIZE
+ are ignored.
+
+* Guile Scripting
+
+ ** Memory ports can now be unbuffered.
+
* Python Scripting
** gdb.Objfile objects have a new attribute "username",
which is the name of the objfile as specified by the user,
without, for example, resolving symlinks.
** You can now write frame unwinders in Python.
+ ** gdb.Type objects have a new method "optimized_out",
+ returning optimized out gdb.Value instance of this type.
+ ** gdb.Value objects have new methods "reference_value" and
+ "const_value" which return a reference to the value and a
+ "const" version of the value respectively.
* New commands
record bts
Start branch trace recording using Branch Trace Store (BTS) format.
+compile print
+ Evaluate expression by using the compiler and print result.
+
+tui enable
+tui disable
+ Explicit commands for enabling and disabling tui mode.
+
+show mpx bound
+set mpx bound on i386 and amd64
+ Support for bound table investigation on Intel MPX enabled applications.
+
+record btrace pt
+record pt
+ Start branch trace recording using Intel Processor Trace format.
+
+maint info btrace
+ Print information about branch tracing internals.
+
+maint btrace packet-history
+ Print the raw branch tracing data.
+
+maint btrace clear-packet-history
+ Discard the stored raw branch tracing data.
+
+maint btrace clear
+ Discard all branch tracing data. It will be fetched and processed
+ anew by the next "record" command.
+
* New options
+set debug dwarf-die
+ Renamed from "set debug dwarf2-die".
+show debug dwarf-die
+ Renamed from "show debug dwarf2-die".
+
+set debug dwarf-read
+ Renamed from "set debug dwarf2-read".
+show debug dwarf-read
+ Renamed from "show debug dwarf2-read".
+
+maint set dwarf always-disassemble
+ Renamed from "maint set dwarf2 always-disassemble".
+maint show dwarf always-disassemble
+ Renamed from "maint show dwarf2 always-disassemble".
+
+maint set dwarf max-cache-age
+ Renamed from "maint set dwarf2 max-cache-age".
+maint show dwarf max-cache-age
+ Renamed from "maint show dwarf2 max-cache-age".
+
+set debug dwarf-line
+show debug dwarf-line
+ Control display of debugging info regarding DWARF line processing.
+
set max-completions
show max-completions
Set the maximum number of candidates to be considered during
to avoid generating large completion lists, the computation of
which can cause the debugger to become temporarily unresponsive.
+set history remove-duplicates
+show history remove-duplicates
+ Control the removal of duplicate history entries.
+
maint set symbol-cache-size
maint show symbol-cache-size
Control the size of the symbol cache.
The obtained size may differ from the requested size. Use "info
record" to see the obtained buffer size.
+set debug linux-namespaces
+show debug linux-namespaces
+ Control display of debugging info regarding Linux namespaces.
+
+set|show record btrace pt buffer-size
+ Set and show the size of the ring buffer used for branch tracing in
+ Intel Processor Trace format.
+ The obtained size may differ from the requested size. Use "info
+ record" to see the obtained buffer size.
+
+maint set|show btrace pt skip-pad
+ Set and show whether PAD packets are skipped when computing the
+ packet history.
+
* The command 'thread apply all' can now support new option '-ascending'
to call its specified command for all threads in ascending order.
Qbtrace-conf:bts:size
Set the requested ring buffer size for branch tracing in BTS format.
+Qbtrace:pt
+ Enable Intel Procesor Trace-based branch tracing for the current
+ process. The remote stub reports support for this packet to GDB's
+ qSupported query.
+
+Qbtrace-conf:pt:size
+ Set the requested ring buffer size for branch tracing in Intel Processor
+ Trace format.
+
swbreak stop reason
Indicates a memory breakpoint instruction was executed, irrespective
of whether it was GDB that planted the breakpoint or the breakpoint
Return the full absolute name of the file that was executed to
create a process running on the remote system.
+vFile:setfs:
+ Select the filesystem on which vFile: operations with filename
+ arguments will operate. This is required for GDB to be able to
+ access files on remote targets where the remote stub does not
+ share a common filesystem with the inferior(s).
+
+fork stop reason
+ Indicates that a fork system call was executed.
+
+vfork stop reason
+ Indicates that a vfork system call was executed.
+
+vforkdone stop reason
+ Indicates that a vfork child of the specified process has executed
+ an exec or exit, allowing the vfork parent to resume execution.
+
+fork-events and vfork-events features in qSupported
+ The qSupported packet allows GDB to request support for fork and
+ vfork events using new 'gdbfeatures' fork-events and vfork-events,
+ and the qSupported response can contain the corresponding
+ 'stubfeatures'. Set and show commands can be used to display
+ whether these features are enabled.
+
+* Extended-remote fork events
+
+ ** GDB now has support for fork events on extended-remote Linux
+ targets. For targets with Linux kernels 2.5.60 and later, this
+ enables follow-fork-mode and detach-on-fork for both fork and
+ vfork, as well as fork and vfork catchpoints.
+
* The info record command now shows the recording format and the
branch tracing configuration for the current thread when using
the btrace record target.
HP/PA running HP-UX hppa*-*-hpux*
Itanium running HP-UX ia64-*-hpux*
+* New configure options
+
+--with-intel-pt
+ This configure option allows the user to build GDB with support for
+ Intel Processor Trace (default: auto). This requires libipt.
+
+--with-libipt-prefix=PATH
+ Specify the path to the version of libipt that GDB should use.
+ $PATH/include should contain the intel-pt.h header and
+ $PATH/lib should contain the libipt.so library.
+
+*** Changes in GDB 7.9.1
+
+* Python Scripting
+
+ ** Xmethods can now specify a result type.
+
*** Changes in GDB 7.9
* GDB now supports hardware watchpoints on x86 GNU Hurd.
can be used to launch native programs even when "set
auto-connect-native-target" is set to off.
-* GDB now supports access to Intel(R) MPX registers on GNU/Linux.
+* GDB now supports access to Intel MPX registers on GNU/Linux.
-* Support for Intel(R) AVX-512 registers on GNU/Linux.
- Support displaying and modifying Intel(R) AVX-512 registers
+* Support for Intel AVX-512 registers on GNU/Linux.
+ Support displaying and modifying Intel AVX-512 registers
$zmm0 - $zmm31 and $k0 - $k7 on GNU/Linux.
* New remote packets
projects / deliverable / binutils-gdb.git / blobdiff