gdb-18.1

[Bruce Dubbs]

New major version.

[Bruce Dubbs]

Changes in GDB 18

• Support for the Common Trace Format (CTF) has been removed. GDB now saves trace information exclusively in its own "tfile" format.

• Support for .gdb_index sections with version less than 7 has been removed.

• Support for DWP (DWARF Package File) version 1 has been removed.

• Support for Guile 2.0 has been removed. Guile 2.2 is now the minimal supported Guile version.

• GDB now accepts --no-escape-args as an alternative to --args on the command line. GDB will not escape special shell characters within arguments after --no-escape-args.

• gdbserver now accepts --no-escape-args as a command line flag. When this flag is used gdbserver will not escape special shell characters within the inferior arguments.

• The add-inferior, clone-inferior, and MI -add-inferior commands will now give a warning, and create the new inferior without a connection, when the current inferior's connection, at the time the command is given, is unshareable. For example, the core-file target cannot be shared between inferiors, nor can the Window native target. These targets could never really be shared. Attempting to share them would usually lead to GDB crashing. GDB now prevents this invalid sharing.

• When connecting to a remote server, if the server supports the new qExecAndArgs packet, then GDB will copy the argument string from the server and update the 'args' setting, as if 'set args ...' had been used. This means that the arguments are visible from GDB using 'show args', and that, if using the extended-remote protocol, subsequent runs of the inferior will use the same arguments as the first run.

• GDB now supports arbitrary (non-standard) baud rates for serial connections to remote targets on systems where the host libc accepts them via cfsetispeed/cfsetospeed, such as glibc 2.42 and later and GNU Hurd. On other systems, existing platform-specific mechanisms are used.

• Support for stabs debug information has been removed.

• Support for mdebug debug information has been removed.

• Support for the binary file format dbx has been removed.

• The format for a saved execution record, created when the command 'record save' is used, has been updated, and previous formats are no longer supported.

• When connected to an extended-remote target GDB can now automatically set the 'remote exec-file' in some cases. GDB will auto set the remote exec-file only if the remote wasn't started with an executable, and the user hasn't used 'set remote exec-file' to set an executable. GDB will auto set the remote exec-file using the current executable if the current executable has a 'target:' prefix, or if the current executable is within the sysroot.

• GDB now adds all type symbols to the .gdb_index section. The index version number has not increased as a consequence of this change. This fixes an issue where GDB could fail to find a type when relying on the index. Any existing indexes should be regenerated.

• Support for Floating Point Mode Register (FPMR) in AArch64.

• When running on the Windows Terminal console, GDB now supports true-color 24-bit colors.

• When running on the Windows Terminal console whose output codepage is 65001, GDB now supports emoji styling and display of UTF-8 encoded text in general. The host charset in that case will be automatically set to UTF-8. (Users can use the Windows 'chcp' command to change the output codepage of the console.)

• The Windows native target now supports scheduler-locking. E.g., "set scheduler-locking on" now works. Previously it gave an error.

• The Windows native target now supports non-stop mode. This feature requires Windows 10 or later.

• Support for native Thread Local Storage (TLS) variables on Windows.

• GDB now normalizes backslashes to forward slashes on Windows.

       E.g., depending on compiler and build system used by your project,
       previously GDB could show a mix of slash styles, like for example:
  
         C:/proj/src\main.c
  
       GDB will now consistently show forward slashes:
  
         C:/proj/src/main.c
  
       This impacts all interpreters, including the CLI, the TUI, the
       GDB/MI interface, and the Debug Adapter Protocol, and affects
       everywhere GDB shows a filename/dirname: source filenames,
       executable filename, shared libraries, the cd/pwd commands, etc.
  

• GDB now supports libipt v2.2 events originating from Event Tracing (set record btrace pt event-tracing on) on a FRED-enabled system and from Trigger Tracing.

• The s390 32-bit target (s390-*) is deprecated and planned for removal in a future release, along with the elf32-s390 target format. configure now emits an error for this target, which can be overridden using --enable-obsolete. Linux Kernel 6.19 removed s390 32-bit compatibility support. Glibc 2.43 and GCC 16.1 have deprecated s390 32-bit, both with the intent to remove it in a future release. The s390 64-bit target (s390x-*) remains supported.

• GDB can now read OS-generated core files on systems with Intel AMX support. The AMX registers themselves are not yet readable, but other xsave state can be read.

• Configure changes

• --with-babeltrace has been removed. The babeltrace library was

only used to help GDB parse Common Trace Format (CTF) data. The support for CTF has also been removed.

• New targets

GNU/Linux/MicroBlaze (gdbserver) microblazeel-*linux*

AArch64 MinGW aarch64-*-mingw*

• Deprecated targets

GNU/Linux/S390 32-bit s390-*-*

• New commands

  set local-environment
  show local-environment
  unset local-environment
    Analogs of the existing "environment" commands that affect GDB's own
    environment.  The local environment is used by "shell", "pipe", and
    other commands that launch a subprocess other than an inferior.
  
  save history FILENAME
    Save the command history to the given file.
  
  save skip FILENAME
    Save all current "skip"s to the given file.
  
  save user FILENAME
    Save all user-defined commands to the given file.
  
  maintenance test-remote-args ARGS
    Test splitting and joining of inferior arguments ARGS as they would
    be split and joined when being passed to a remote target.
  
  set debug gnu-ifunc on|off
  show debug gnu-ifunc
    Turn on or off debug messages related to GNU ifunc resolution.
  
  set debug ctf on|off
  show debug ctf
    Turn on or off debug messages about Compact C Type Format (CTF)
    reading.
  
  set progress-bars enabled on|off
  show progress-bars enabled
    Allows the progress bars, used when debuginfod is downloading
    content, to be disabled (the set command), or to see if
    progress-bars are currently enabled or not (the show command).
  
  info proc environ
    Print the initial environment variables of the specified process.
    Supported on Linux.
  
  delete skip
  enable skip
  disable skip
    These are new aliases for 'skip delete', 'skip enable', and 'skip
    disable' respectively.
  

• MI changes

• The "-trace-save" command no longer supports the "-ctf" flag.

• Changed commands

tsave

This command no longer supports the "-ctf" flag.

maintenance info program-spaces

This command no longer displays the core file name.

info inferiors

If an inferior has a core file loaded, then this will be displayed as an additional line under the inferior's table entry in the output.

New command class for help

The new command class "essential" has been added, which is a set of commands that we, as developers, believe would be close to a minimal set of commands for a new user of GDB.

info locals

GDB now shows the "shadowed" annotation and the location information for variables that are shadowed, or which are shadowing.

• Removed commands

target ctf

Support for the Common Trace Format (CTF) has been removed.

maint check psymtabs
maint info psymtabs
maint print psymbols
  These commands have been removed, as GDB no longer uses partial
  symbol tables internally.

• Debugger Adapter Protocol changes

• Unhandled Ada exceptions can now be caught using the "unhandled" exception filter.

• The launch and attach requests now accept the adaSourceCharset parameter.

• The attach request now accepts the coreFile parameter.

• Constants are now returned in scopes.

• Changed remote packets

  single-inf-arg in qSupported
    The new single-inf-arg feature within the qSupported packet allows
    GDB to inform the stub that it would like to send the inferior
    arguments as a single string within the vRun packet.  The stub can
    reply with the single-inf-arg feature to indicate that it is able to
    accept arguments as a single string.
  
  set args
  run
  start
  starti
    These commands now all allow for entering inferior arguments that
    contain a newline character.  The newline must be contained within a
    single or double quoted argument.
  
  * New remote packets
  
  qExecAndArgs
    This packet returns the executable filename and argument string with
    which the server was started.  If no such information was given to
    the server then this is reflected in the reply.
  
  * Python API
  
    ** New class gdb.Style for representing styles, a collection of
       foreground and background gdb.Color objects, and an intensity.
  
    ** New constants gdb.INTENSITY_NORMAL, gdb.INTENSITY_BOLD, and
       gdb.INTENSITY_DIM for use with gdb.Style when representing
       intensities.
  
    ** New gdb.StyleParameterSet for creating custom style settings.
       Use gdb.StyleParameterSet(NAME) to create 'set style NAME ...'
       and 'show style NAME ...' parameters.
  
    ** The gdb.write() function now takes an additional, optional,
       'style' argument, which can be used to style the output.
  
    ** New gdb.Corefile class which represents a loaded core file.  This
       has an attribute Corefile.filename, the file name of the loaded
       core file, and a method Corefile.is_valid(), which returns False
       when a Corefile object becomes invalid (e.g. when the core file
       is unloaded).  There is also Corefile.mapped_files() which
       returns a list of CorefileMappedFile objects, representing files
       that were mapped into the core file when it was created.
  
    ** New gdb.CorefileMappedFile type representing a file that was
       mapped when the core file was created.  Has read-only attributes
       filename (string), build_id (string), is_main_executable
       (boolean), and regions (list of CorefileMappedFileRegion objects).
  
    ** New gdb.CorefileMappedFileRegion type, which represents a mapped
       region of a file (see gdb.CorefileMappedFile above).  Has
       read-only attributes start, end, and file_offset.
  
    ** New Inferior.corefile attribute.  This read only attribute
       contains the gdb.Corefile object if a core file is loaded into
       the inferior, otherwise, this contains None.
  
    ** New event registry gdb.events.selected_context that emits a
       SelectedContextEvent event whenever the user changes the inferior
       context.  The context consists of which inferior, thread, and
       frame are currently selected.  The event object has 'inferior',
       'thread' and 'frame' attributes containing gdb.Inferior,
       gdb.InferiorThread, and gdb.Frame objects respectively.
  
    ** New method gdb.Symtab.source_lines(start, end, unstyled).  This
       returns a tuple of strings, each string represents a single
       source line for the file associated with the symtab.  The 'start'
       and 'end' are line numbers, and allow for only some lines to be
       returned, these default to the first and last lines in the file
       respectively.  If 'unstyled' is true then the returned lines will
       have no styling applied, otherwise, styling will be applied if
       the appropriate user setting is enabled, and GDB knows how to
       style this source file.
  
    ** The Architecture.disassemble method accepts a new 'styling'
       argument, which defaults to False.  When set to True the 'asm'
       strings in the disassembler output can contain ANSI escape
       sequences to indicate styling.
  
    ** New gdb.Block.ranges attribute.  This read only attribute contains
       a tuple of pairs each representing a single range.  Contiguous blocks
       have only one range.
  
    ** New event registry gdb.events.corefile_changed, which emits a
       CorefileChangedEvent whenever the core file associated with an
       inferior changes.  The event has an 'inferior' attribute which is
       the gdb.Inferior in which the core file has changed.
  

• Guile API

Procedures 'memory-port-read-buffer-size',

'set-memory-port-read-buffer-size!', 'memory-port-write-buffer-size', and 'set-memory-port-write-buffer-size!' have been removed. They were deprecated since GDB 10. Users who need to control the size of a memory port's internal buffer can use the 'setvbuf' procedure.

• Removed targets and native configurations

GDB no longer supports AIX 7.1. The minimum supported AIX version is now AIX 7.2 TL5. GDB will only support DWARF debugging in AIX, going forward.

[Bruce Dubbs]

Fixed at commit 59f8fb50a1.