What has changed in GDB?

(Organized release by release)

*** Changes since GDB 7.12

* Building GDB and GDBserver now requires a C++11 compiler.

For example, GCC 4.8 or later.

It is no longer possible to build GDB or GDBserver with a C

compiler. The --disable-build-with-cxx configure option has been

removed.

* Building GDB and GDBserver now requires GNU make >= 3.81.

It is no longer supported to build GDB or GDBserver with another

implementation of the make program or an earlier version of GNU make.

* Native debugging on MS-Windows supports command-line redirection

Command-line arguments used for starting programs on MS-Windows can

now include redirection symbols supported by native Windows shells,

such as '<', '>', '>>', '2>&1', etc. This affects GDB commands such

as "run", "start", and "set args", as well as the corresponding MI

features.

* Support for thread names on MS-Windows.

GDB now catches and handles the special exception that programs

running on MS-Windows use to assign names to threads in the

debugger.

* Support for Java programs compiled with gcj has been removed.

* User commands now accept an unlimited number of arguments.

Previously, only up to 10 was accepted.

* The "eval" command now expands user-defined command arguments.

This makes it easier to process a variable number of arguments:

define mycommand

set $i = 0

while $i < $argc

eval "print $arg%d", $i

set $i = $i + 1

end

end

* New targets

Synopsys ARC arc*-*-elf32

*** Changes in GDB 7.12

* GDB and GDBserver now build with a C++ compiler by default.

The --enable-build-with-cxx configure option is now enabled by

default. One must now explicitly configure with

--disable-build-with-cxx in order to build with a C compiler. This

option will be removed in a future release.

* GDBserver now supports recording btrace without maintaining an active

GDB connection.

* GDB now supports a negative repeat count in the 'x' command to examine

memory backward from the given address. For example:

(gdb) bt

#0 Func1 (n=42, p=0x40061c "hogehoge") at main.cpp:4

#1 0x400580 in main (argc=1, argv=0x7fffffffe5c8) at main.cpp:8

(gdb) x/-5i 0x0000000000400580

0x40056a <main(int, char**)+8>: mov %edi,-0x4(%rbp)

0x40056d <main(int, char**)+11>: mov %rsi,-0x10(%rbp)

0x400571 <main(int, char**)+15>: mov $0x40061c,%esi

0x400576 <main(int, char**)+20>: mov $0x2a,%edi

0x40057b <main(int, char**)+25>:

callq 0x400536 <Func1(int, char const*)>

* Fortran: Support structures with fields of dynamic types and

arrays of dynamic types.

* GDB now supports multibit bitfields and enums in target register

descriptions.

* New Python-based convenience function $_as_string(val), which returns

the textual representation of a value. This function is especially

useful to obtain the text label of an enum value.

* 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

* Rust language support.

GDB now supports debugging programs written in the Rust programming

language. See https://www.rust-lang.org/ for more information about

Rust.

* Support for running interpreters on specified input/output devices

GDB now supports a new mechanism that allows frontends to provide

fully featured GDB console views, as a better alternative to

building such views on top of the "-interpreter-exec console"

command. See the new "new-ui" command below. With that command,

frontends can now start GDB in the traditional command-line mode

running in an embedded terminal emulator widget, and create a

separate MI interpreter running on a specified i/o device. In this

way, GDB handles line editing, history, tab completion, etc. in the

console all by itself, and the GUI uses the separate MI interpreter

for its own control and synchronization, invisible to the command

line.

* The "catch syscall" command catches groups of related syscalls.

The "catch syscall" command now supports catching a group of related

syscalls using the 'group:' or 'g:' prefix.

* New commands

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.

maint info line-table REGEXP

Display the contents of GDB's internal line table data struture.

maint selftest

Run any GDB unit tests that were compiled in.

new-ui INTERP TTY

Start a new user interface instance running INTERP as interpreter,

using the TTY file for input/output.

* Python Scripting

** gdb.Breakpoint objects have a new attribute "pending", which

indicates whether the breakpoint is pending.

** Three new breakpoint-related events have been added:

gdb.breakpoint_created, gdb.breakpoint_modified, and

gdb.breakpoint_deleted.

signal-event EVENTID

Signal ("set") the given MS-Windows event object. This is used in

conjunction with the Windows JIT debugging (AeDebug) support, where

the OS suspends a crashing process until a debugger can attach to

it. Resuming the crashing process, in order to debug it, is done by

signalling an event.

* Support for tracepoints and fast tracepoints on s390-linux and s390x-linux

was added in GDBserver, including JIT compiling fast tracepoint's

conditional expression bytecode into native code.

* Support for various remote target protocols and ROM monitors has

been removed:

target m32rsdi Remote M32R debugging over SDI

target mips MIPS remote debugging protocol

target pmon PMON ROM monitor

target ddb NEC's DDB variant of PMON for Vr4300

target rockhopper NEC RockHopper variant of PMON

target lsi LSI variant of PMO

* Support for tracepoints and fast tracepoints on powerpc-linux,

powerpc64-linux, and powerpc64le-linux was added in GDBserver,

including JIT compiling fast tracepoint's conditional expression

bytecode into native code.

* MI async record =record-started now includes the method and format used for

recording. For example:

=record-started,thread-group="i1",method="btrace",format="bts"

* MI async record =thread-selected now includes the frame field. For example:

=thread-selected,id="3",frame={level="0",addr="0x00000000004007c0"}

* New targets

Andes NDS32 nds32*-*-elf

*** 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.

* 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

Enables/disables catching syscalls from the inferior process.

The remote stub reports support for this packet to GDB's qSupported query.

syscall_entry stop reason

Indicates that a syscall was just called.

syscall_return stop reason

Indicates that a syscall just returned.

* 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

to specify the types of memory mappings that will be included in a

corefile. For more information, please refer to the manual page of

"core(5)". GDB also has a new command: "set use-coredump-filter

on|off". It allows to set whether GDB will read the content of the

/proc/PID/coredump_filter file when generating a corefile.

* The "info os" command on GNU/Linux can now display information on

cpu information :

"info os cpus" Listing of all cpus/cores on the system

* GDB has two new commands: "set serial parity odd|even|none" and

"show serial parity". These allows to set or show parity for the

remote serial I/O.

* The "info source" command now displays the producer string if it was

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

"remote:". The default sysroot has been changed from "" to

"target:". "remote:" is automatically converted to "target:" for

backward compatibility.

* The system root specified by "set sysroot" will be prepended to the

filename of the main executable (if reported to GDB as absolute by

the operating system) when starting processes remotely, and when

attaching to already-running local or remote processes.

* GDB now supports automatic location and retrieval of executable

files from remote targets. Remote debugging can now be initiated

using only a "target remote" or "target extended-remote" command

(no "set sysroot" or "file" commands are required). See "New remote

packets" below.

* 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

maint print symbol-cache

Print the contents of the symbol cache.

maint print symbol-cache-statistics

Print statistics of symbol cache usage.

maint flush-symbol-cache

Flush the contents of the symbol cache.

record btrace bts

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

completion. The default value is 200. This limit allows GDB

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.

set|show record btrace bts buffer-size

Set and show the size of the ring buffer used for branch tracing in

BTS format.

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.

* Python/Guile scripting

** GDB now supports auto-loading of Python/Guile scripts contained in the

special section named `.debug_gdb_scripts'.

* New remote packets

qXfer:btrace-conf:read

Return the branch trace configuration for the current thread.

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

is hardcoded in the program. This is required for correct non-stop

mode operation.

hwbreak stop reason

Indicates the target stopped for a hardware breakpoint. This is

required for correct non-stop mode operation.

vFile:fstat:

Return information about files on the remote system.

qXfer:exec-file:read

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.

For the BTS format, it shows the ring buffer size.

* GDB now has support for DTrace USDT (Userland Static Defined

Tracing) probes. The supported targets are x86_64-*-linux-gnu.

* GDB now supports access to vector registers on S/390 GNU/Linux

targets.

* Removed command line options

-xdb HP-UX XDB compatibility mode.

* Removed targets and native configurations

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.

* Python Scripting

** You can now access frame registers from Python scripts.

** New attribute 'producer' for gdb.Symtab objects.

** gdb.Objfile objects have a new attribute "progspace",

which is the gdb.Progspace object of the containing program space.

** gdb.Objfile objects have a new attribute "owner".

** gdb.Objfile objects have a new attribute "build_id",

which is the build ID generated when the file was built.

** gdb.Objfile objects have a new method "add_separate_debug_file".

** A new event "gdb.clear_objfiles" has been added, triggered when

selecting a new file to debug.

** You can now add attributes to gdb.Objfile and gdb.Progspace objects.

** New function gdb.lookup_objfile.

New events which are triggered when GDB modifies the state of the

inferior.

** gdb.events.inferior_call_pre: Function call is about to be made.

** gdb.events.inferior_call_post: Function call has just been made.

** gdb.events.memory_changed: A memory location has been altered.

** gdb.events.register_changed: A register has been altered.

* New Python-based convenience functions:

** $_caller_is(name [, number_of_frames])

** $_caller_matches(regexp [, number_of_frames])

** $_any_caller_is(name [, number_of_frames])

** $_any_caller_matches(regexp [, number_of_frames])

* GDB now supports the compilation and injection of source code into

the inferior. GDB will use GCC 5.0 or higher built with libcc1.so

to compile the source code to object code, and if successful, inject

and execute that code within the current context of the inferior.

Currently the C language is supported. The commands used to

interface with this new feature are:

compile code [-raw|-r] [--] [source code]

compile file [-raw|-r] filename

* New commands

demangle [-l language] [--] name

Demangle "name" in the specified language, or the current language

if elided. This command is renamed from the "maint demangle" command.

The latter is kept as a no-op to avoid "maint demangle" being interpreted

as "maint demangler-warning".

queue-signal signal-name-or-number

Queue a signal to be delivered to the thread when it is resumed.

add-auto-load-scripts-directory directory

Add entries to the list of directories from which to load auto-loaded

scripts.

maint print user-registers

List all currently available "user" registers.

compile code [-r|-raw] [--] [source code]

Compile, inject, and execute in the inferior the executable object

code produced by compiling the provided source code.

compile file [-r|-raw] filename

Compile and inject into the inferior the executable object code

produced by compiling the source code stored in the filename

provided.

* On resume, GDB now always passes the signal the program had stopped

for to the thread the signal was sent to, even if the user changed

threads before resuming. Previously GDB would often (but not

always) deliver the signal to the thread that happens to be current

at resume time.

* Conversely, the "signal" command now consistently delivers the

requested signal to the current thread. GDB now asks for

confirmation if the program had stopped for a signal and the user

switched threads meanwhile.

* "breakpoint always-inserted" modes "off" and "auto" merged.

Now, when 'breakpoint always-inserted mode' is set to "off", GDB

won't remove breakpoints from the target until all threads stop,

even in non-stop mode. The "auto" mode has been removed, and "off"

is now the default mode.

* New options

set debug symbol-lookup

show debug symbol-lookup

Control display of debugging info regarding symbol lookup.

* MI changes

** The -list-thread-groups command outputs an exit-code field for

inferiors that have exited.

* New targets

MIPS SDE mips*-sde*-elf*

* Removed targets

Support for these obsolete configurations has been removed.

Alpha running OSF/1 (or Tru64) alpha*-*-osf*

SGI Irix-5.x mips-*-irix5*

SGI Irix-6.x mips-*-irix6*

VAX running (4.2 - 4.3 Reno) BSD vax-*-bsd*

VAX running Ultrix vax-*-ultrix*

* The "dll-symbols" command, and its two aliases ("add-shared-symbol-files"

and "assf"), have been removed. Use the "sharedlibrary" command, or

its alias "share", instead.

*** Changes in GDB 7.8

* New command line options

-D data-directory

This is an alias for the --data-directory option.

* GDB supports printing and modifying of variable length automatic arrays

as specified in ISO C99.

* The ARM simulator now supports instruction level tracing

with or without disassembly.

* Guile scripting

GDB now has support for scripting using Guile. Whether this is

available is determined at configure time.

Guile version 2.0 or greater is required.

Guile version 2.0.9 is well tested, earlier 2.0 versions are not.

* New commands (for set/show, see "New options" below)

guile [code]

gu [code]

Invoke CODE by passing it to the Guile interpreter.

guile-repl

gr

Start a Guile interactive prompt (or "repl" for "read-eval-print loop").

info auto-load guile-scripts [regexp]

Print the list of automatically loaded Guile scripts.

* The source command is now capable of sourcing Guile scripts.

This feature is dependent on the debugger being built with Guile support.

* New options

set print symbol-loading (off|brief|full)

show print symbol-loading

Control whether to print informational messages when loading symbol

information for a file. The default is "full", but when debugging

programs with large numbers of shared libraries the amount of output

becomes less useful.

set guile print-stack (none|message|full)

show guile print-stack

Show a stack trace when an error is encountered in a Guile script.

set auto-load guile-scripts (on|off)

show auto-load guile-scripts

Control auto-loading of Guile script files.

maint ada set ignore-descriptive-types (on|off)

maint ada show ignore-descriptive-types

Control whether the debugger should ignore descriptive types in Ada

programs. The default is not to ignore the descriptive types. See

the user manual for more details on descriptive types and the intended

usage of this option.

set auto-connect-native-target

Control whether GDB is allowed to automatically connect to the

native target for the run, attach, etc. commands when not connected

to any target yet. See also "target native" below.

set record btrace replay-memory-access (read-only|read-write)

show record btrace replay-memory-access

Control what memory accesses are allowed during replay.

maint set target-async (on|off)

maint show target-async

This controls whether GDB targets operate in synchronous or

asynchronous mode. Normally the default is asynchronous, if it is

available; but this can be changed to more easily debug problems

occurring only in synchronous mode.

set mi-async (on|off)

show mi-async

Control whether MI asynchronous mode is preferred. This supersedes

"set target-async" of previous GDB versions.

* "set target-async" is deprecated as a CLI option and is now an alias

for "set mi-async" (only puts MI into async mode).

* Background execution commands (e.g., "c&", "s&", etc.) are now

possible ``out of the box'' if the target supports them. Previously

the user would need to explicitly enable the possibility with the

"set target-async on" command.

* New features in the GDB remote stub, GDBserver

** New option --debug-format=option1[,option2,...] allows one to add

additional text to each output. At present only timestamps

are supported: --debug-format=timestamps.

Timestamps can also be turned on with the

"monitor set debug-format timestamps" command from GDB.

* The 'record instruction-history' command now starts counting instructions

at one. This also affects the instruction ranges reported by the

'record function-call-history' command when given the /i modifier.

* The command 'record function-call-history' supports a new modifier '/c' to

indent the function names based on their call stack depth.

The fields for the '/i' and '/l' modifier have been reordered.

The source line range is now prefixed with 'at'.

The instruction range is now prefixed with 'inst'.

Both ranges are now printed as '<from>, <to>' to allow copy&paste to the

"record instruction-history" and "list" commands.

* The ranges given as arguments to the 'record function-call-history' and

'record instruction-history' commands are now inclusive.

* The btrace record target now supports the 'record goto' command.

For locations inside the execution trace, the back trace is computed

based on the information stored in the execution trace.

* The btrace record target supports limited reverse execution and replay.

The target does not record data and therefore does not allow reading

memory or registers.

* The "catch syscall" command now works on s390*-linux* targets.

* The "compare-sections" command is no longer specific to target

remote. It now works with all targets.

* All native targets are now consistently called "native".

Consequently, the "target child", "target GNU", "target djgpp",

"target procfs" (Solaris/Irix/OSF/AIX) and "target darwin-child"

commands have been replaced with "target native". The QNX/NTO port

leaves the "procfs" target in place and adds a "native" target for

consistency with other ports. The impact on users should be minimal

as these commands previously either throwed an error, or were

no-ops. The target's name is visible in the output of the following

commands: "help target", "info target", "info files", "maint print

target-stack".

* The "target native" command now connects to the native target. This

can be used to launch native programs even when "set

auto-connect-native-target" is set to off.

* GDB now supports access to Intel MPX registers on GNU/Linux.

* 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

qXfer:btrace:read's annex

The qXfer:btrace:read packet supports a new annex 'delta' to read