GNU C Library NEWS -- history of user-visible changes.
Copyright (C) 1992-2023 Free Software Foundation, Inc.
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Version 2.38

Major new features:

* When C2X features are enabled and the base argument is 0 or 2, the
  following functions support binary integers prefixed by 0b or 0B as
  input: strtol, strtoll, strtoul, strtoull, strtol_l, strtoll_l,
  strtoul_l, strtoull_l, strtoimax, strtoumax, strtoq, strtouq, wcstol,
  wcstoll, wcstoul, wcstoull, wcstol_l, wcstoll_l, wcstoul_l,
  wcstoull_l, wcstoimax, wcstoumax, wcstoq, wcstouq.  Similarly, the
  following functions support binary integers prefixed by 0b or 0B as
  input to the %i format: fscanf, scanf, sscanf, vscanf, vsscanf,
  vfscanf, fwscanf, wscanf, swscanf, vfwscanf, vwscanf, vswscanf; those
  functions also support the %b format for binary integers, with or
  without such a prefix and independent of standards mode.

* PRIb*, PRIB* and SCNb* macros from C2X have been added to
  <inttypes.h>.

* printf-family functions now support the wN format length modifiers for
  arguments of type intN_t, int_leastN_t, uintN_t or uint_leastN_t (for
  example, %w32d to print int32_t or int_least32_t in decimal, or %w32x
  to print uint32_t or uint_least32_t in hexadecimal) and the wfN format
  length modifiers for arguments of type int_fastN_t or uint_fastN_t, as
  specified in draft ISO C2X.

* A new tunable, glibc.pthread.stack_hugetlb, can be used to disable
  Transparent Huge Pages (THP) in stack allocation at pthread_create.

* Support for x86_64 running on Hurd has been added.  This port requires
  as least binutils 2.40 and GCC 13:

    - x86_64-gnu

* Vector math library libmvec support has been added to AArch64.  It
  requires GCC version >= 10.1.0.  It can be disabled via
  "--disable-mathvec", however that is not a supported configuration as
  it changes the ABI. The symbol names follow the AArch64 vector ABI,
  they are declared in math.h and have to be called manually at this point.

* The strlcpy and strlcat functions have been added.  They are derived
  from OpenBSD, and are expected to be added to a future POSIX version.

* A new configure option, "--enable-fortify-source", can be used to build the
  GNU C Library with _FORTIFY_SOURCE. The level of fortification can either be
  provided, or is set to the highest value supported by the compiler. If not
  explicitly enabled, then fortify source is forcibly disabled so to keep
  original behavior unchanged.

Deprecated and removed features, and other changes affecting compatibility:

* libcrypt is no longer built by default; one may use the "--enable-crypt"
  option to build libcrypt.  libcrypt is likely to be removed from the
  GNU C Library in a future release, so it is recommended that
  applications port away from it to an alternative such as libxcrypt.

* In the Linux kernel for the hppa/parisc architecture some of the
  MADV_XXX constants were changed to have the same values as the other
  architectures.  New programs compiled with this glibc version and which
  use the madvise call will require at least Linux kernel version 6.2,
  alternatively stable kernels from versions 6.1.6, 5.15.87, 5.10.163,
  5.4.228, 4.19.270 or 4.14.303.

* The "--disable-experimental-malloc" option is no longer available.  The
  per-thread cache can still be disabled per-application using tunables
  (glibc.malloc.tcache_count set to zero).

* The configure option "--enable-tunables" has been removed.  The tunable
  feature is now always enabled.

Changes to build and runtime requirements:

* Building libmvec on AArch64 requires at a minimum GCC 10.1.0 for SVE
  ACLE.

Security related changes:

  CVE-2023-25139: When the printf family of functions is called with a
  format specifier that uses an <apostrophe> (enable grouping) and a
  minimum width specifier, the resulting output could be larger than
  reasonably expected by a caller that computed a tight bound on the
  buffer size.  The resulting larger than expected output could result
  in a buffer overflow in the printf family of functions.

  CVE-2023-4911: If a tunable of the form NAME=NAME=VAL is passed in the
  environment of a setuid program and NAME is valid, it may result in a
  buffer overflow, which could be exploited to achieve escalated
  privileges.  This flaw was introduced in glibc 2.34.

The following bugs are resolved with this release:

  [178] string: Please add strlcpy and strlcat (attached)
  [14697] nptl: Behavior of exit is nonconformant with respect to
    threads and stdio
  [15142] stdio: Missing locking in _IO_cleanup
  [18096] glob: null deref in wordexp/parse_dollars/parse_arith
  [18906] stdio: fopen: ccs value may affect open mode
  [24466] stdio: Feature request: provide special printf formats for
    intXX_t
  [25457] nss: hosts lookup fails for ipv4mapped ipv6 addresses
  [28519] libc: system and popen should pass "--" between /bin/sh and
    argument
  [29016] stdio: popen() sets errno to ENOMEM when shell does not exist
  [29591] string: wcsnlen length can overflow in page cross case.
  [30053] time: strftime %s returns -1 after 2038 on 32 bits systems
  [30068] stdio: incorrect printf output for integers with thousands
    separator and width field (CVE-2023-25139)
  [30111] time: support_descriptors_list fails after 2038 on 32 bits
    systems
  [30125] dynamic-link: [regression, bisected] glibc-2.37 creates new
    symlink for libraries without soname
  [30130] math: [s390] The _FPU_SETCW macro yields compile error with
    Clang
  [30156] time: Potential ntp_gettime abi break
  [30235] libc: Missing fallback in getlogin if loginuid is unset
  [30258] dynamic-link: sprof cannot read and display shared object
    profiling data correctly
  [30263] libc: Add test coverage for abs(), labs(), and llabs().
  [30305] math: Incorrect asm constraint in feraiseexcept on x86-64
  [30402] libc: FAIL: elf/tst-glibcelf
  [30425] dynamic-link: Symbol lookup during dlclose may fail
    unnecessarily
  [30435] dynamic-link: Root dir wrongly marked as nonexist in open_path
  [30477] libc: [RISCV]: time64 does not work on riscv32
  [30515] dynamic-link: _dl_find_object incorrectly returns 1 during
    early startup
  [30527] network: resolv_conf lock not unlocked on allocation failure
  [30550] math: powerpc64le: GCC-specific code for isinf() is being used
    on clang
  [30555] string: strerror can incorrectly return NULL
  [30579] malloc: trim_threshold in realloc lead to high memory usage
  [30662] nscd: Group and password cache use errno in place of errval

Version 2.37

Major new features:

* The getent tool now supports the --no-addrconfig option. The output of
  getent with --no-addrconfig may contain addresses of families not
  configured on the current host i.e. as-if you had not passed
  AI_ADDRCONFIG to getaddrinfo calls.

Deprecated and removed features, and other changes affecting compatibility:

* The dynamic linker no longer loads shared objects from the "tls"
  subdirectories on the library search path or the subdirectory that
  corresponds to the AT_PLATFORM system name, or employs the legacy AT_HWCAP
  search mechanism, which was deprecated in version 2.33.

Security related changes:

  CVE-2022-39046: When the syslog function is passed a crafted input
  string larger than 1024 bytes, it reads uninitialized memory from the
  heap and prints it to the target log file, potentially revealing a
  portion of the contents of the heap.

The following bugs are resolved with this release:

  [12154] network: Cannot resolve hosts which have wildcard aliases
  [12165] libc: readdir: Do not skip entries with zero d_ino values
  [19444] build: build failures with -O1 due to -Wmaybe-uninitialized
  [24774] nptl: pthread_rwlock_timedwrlock stalls on ARM
  [24816] nss: nss/tst-nss-files-hosts-long fails when no interface has
    AF_INET6 address (ie docker)
  [27087] stdio: PowerPC: Redefinition error with Clang from IEEE
    redirection headers
  [28846] network: CMSG_NXTHDR may trigger -Wstrict-overflow warning
  [28937] dynamic-link: New DSO dependency sorter does not put new map
    first if in a cycle
  [29249] libc: csu/libc-tls.c:202: undefined reference to
    `_startup_fatal_not_constant'
  [29305] network: Inefficient buffer space usage in nss_dns for
    gethostbyname and other functions
  [29375] libc: don't hide MAP_ANONYMOUS behind _GNU_SOURCE
  [29402] nscd: nscd: No such file or directory
  [29415] nscd: getaddrinfo with AI_ADDRCONFIG returns addresses with
    wrong family
  [29427] dynamic-link: Inconsistency detected by ld.so: dl-printf.c:
    200: _dl_debug_vdprintf: Assertion `! "invalid format specifier"'
    failed!
  [29463] math: math/test-float128-y1 fails on x86_64
  [29485] build: Make hangs when the test misc/tst-pidfile returns
    FAIL_UNSUPPORTED
  [29490] dynamic-link: [bisected] new __brk_call causes dynamic loader
    segfault on alpha
  [29499] build: Check failed on misc/tst-glibcsyscalls while building
    for RISCV64 on a unmatched hardware
  [29501] build: Check failed on stdlib/tst-strfrom while building for
    RISCV64 on a unmatched hardware
  [29502] libc: alpha sys/acct.h out of date
  [29514] build: Need to use -fPIE not -fpie
  [29528] dynamic-link: __libc_early_init not called after dlmopen that
    reuses namespace
  [29536] libc: syslog fail to create large messages (CVE-2022-39046)
  [29537] libc: [2.34 regression]: Alignment issue on m68k when using
    futexes on qemu-user
  [29539] libc: LD_TRACE_LOADED_OBJECTS changed how vDSO library are
    printed
  [29544] libc: Regression in syslog(3) calls breaks RFC due to extra
    whitespace
  [29564] build: Incorrect way to change MAKEFLAGS in Makerules
  [29576] build: librtld.os: in function `_dl_start_profile':
    (.text+0x9444): undefined reference to `strcpy'
  [29578] libc: Definition of SUN_LEN() is wrong
  [29583] build: iconv failures on 32bit platform due to missing large
    file support
  [29600] dynamic-link: dlmopen hangs after loading certain libraries
  [29604] localedata: Update locale data to Unicode 15.0.0
  [29605] nscd: Regression in NSCD backend of getaddrinfo
  [29607] nscd: nscd repeatably crashes calling __strlen_avx2 when hosts
    cache is enabled
  [29611] string: Optimized AVX2 string functions unconditionally use
    BMI2 instructions
  [29624] malloc: errno is not cleared when entering main
  [29638] libc: stdlib: arc4random fallback is never used
  [29657] libc: Incorrect struct stat for 64-bit time on linux/generic
    platforms
  [29698] build: Configuring for AArch32 on ARMv8+ disables
    optimizations
  [29727] locale: __strtol_internal out-of-bounds read when parsing
    thousands grouping
  [29730] libc: broken y2038 support in fstatat on MIPS N64
  [29746] libc: ppoll() does not switch to __ppoll64 when
    -D_TIME_BITS=64 and -D_FORTIFY_SOURCE=2 is given on 32bit
  [29771] libc: Restore IPC_64 support in sysvipc *ctl functions
  [29780] build: possible parallel make issue in glibc-2.36 (siglist-
    aux.S: No such file or directory)
  [29864] libc: __libc_start_main() should obtain program headers
    address (_dl_phdr) from the auxv, not the ELF header.
  [29951] time: daylight variable not set correctly if last DST change
    coincides with offset change
  [30039] stdio: __vsprintf_internal does not handle unspecified buffer
    length in fortify mode

Version 2.36

Major new features:

* Support for DT_RELR relative relocation format has been added to
  glibc.  This is a new ELF dynamic tag that improves the size of
  relative relocations in shared object files and position independent
  executables (PIE).  DT_RELR generation requires linker support for
  -z pack-relative-relocs option, which is supported for some targets
  in recent binutils versions.  Lazy binding doesn't apply to DT_RELR.

* On Linux, the pidfd_open, pidfd_getfd, and pidfd_send_signal functions
  have been added.  The pidfd functionality provides access to a process
  while avoiding the issue of PID reuse on traditional Unix systems.

* On Linux, the process_madvise function has been added. It has the
  same functionality as madvise but alters the target process identified
  by the pidfd.

* On Linux, the process_mrelease function has been added.  It allows a
  caller to release the memory of a dying process.  The release of the
  memory is carried out in the context of the caller, using the caller's
  CPU affinity, and priority with CPU usage accounted to the caller.

* The “no-aaaa” DNS stub resolver option has been added.  System
  administrators can use it to suppress AAAA queries made by the stub
  resolver, including AAAA lookups triggered by NSS-based interfaces
  such as getaddrinfo.  Only DNS lookups are affected: IPv6 data in
  /etc/hosts is still used, getaddrinfo with AI_PASSIVE will still
  produce IPv6 addresses, and configured IPv6 name servers are still
  used.  To produce correct Name Error (NXDOMAIN) results, AAAA queries
  are translated to A queries.  The new resolver option is intended
  primarily for diagnostic purposes, to rule out that AAAA DNS queries
  have adverse impact.  It is incompatible with EDNS0 usage and DNSSEC
  validation by applications.

* On Linux, the fsopen, fsmount, move_mount, fsconfig, fspick, open_tree,
  and mount_setattr have been added.  They are part of the new Linux kernel
  mount APIs that allow applications to more flexibly configure and operate
  on filesystem mounts.  The new mount APIs are specifically designed to work
  with namespaces.

* localedef now accepts locale definition files encoded in UTF-8.
  Previously, input bytes not within the ASCII range resulted in
  unpredictable output.

* Support for the mbrtoc8 and c8rtomb multibyte/UTF-8 character conversion
  functions has been added per the ISO C2X N2653 and C++20 P0482R6 proposals.
  Support for the char8_t typedef has been added per the ISO C2X N2653
  proposal.  The functions are declared in uchar.h in C2X mode or when the
  _GNU_SOURCE macro or C++20 __cpp_char8_t feature test macro is defined.
  The char8_t typedef is declared in uchar.h in C2X mode or when the
  _GNU_SOURCE macro is defined and the C++20 __cpp_char8_t feature test macro
  is not defined (if __cpp_char8_t is defined, then char8_t is a builtin type).

* The functions arc4random, arc4random_buf, and arc4random_uniform have been
  added.  The functions wrap getrandom and/or /dev/urandom to return high-
  quality randomness from the kernel.

* Support for LoongArch running on Linux has been added.  This port requires
  as least binutils 2.38, GCC 12, and Linux 5.19.  Currently only hard-float
  ABI is supported:

    - loongarch64-linux-gnu

  The LoongArch ABI is 64-bit little-endian.

Deprecated and removed features, and other changes affecting compatibility:

* Support for prelink will be removed in the next release; this includes
  removal of the LD_TRACE_PRELINKING, and LD_USE_LOAD_BIAS, environment
  variables and their functionality in the dynamic loader.

* The Linux kernel version check has been removed along with the
  LD_ASSUME_KERNEL environment variable.  The minimum kernel used to built
  glibc is still provided through NT_GNU_ABI_TAG ELF note and also printed
  when libc.so is issued directly.

* On Linux, The LD_LIBRARY_VERSION environment variable has been removed.

The following bugs are resolved with this release:

  [14932] dynamic-link: dlsym(handle, "foo") and dlsym(RTLD_NEXT, "foo")
    return different result with versioned "foo"
  [16355] libc: syslog.h's SYSLOG_NAMES namespace violation and utter
    mess
  [23293] dynamic-link: aarch64: getauxval is broken when run as ld.so
    ./exe and ld.so adjusts argv on the stack
  [24595] nptl: [2.28 Regression]: Deadlock in atfork handler which
    calls dlclose
  [25744] locale: mbrtowc with Big5-HKSCS returns 2 instead of 1 when
    consuming the second byte of certain double byte characters
  [25812] stdio: Libio vtable protection is sometimes only partially
    enforced
  [27054] libc: pthread_atfork handlers that call pthread_atfork
    deadlock
  [27924] dynamic-link: ld.so: Support DT_RELR relative relocation
    format
  [28128] build: declare_symbol_alias doesn't work for assembly codes
  [28566] network: getnameinfo with NI_NOFQDN is not thread safe
  [28752] nss: Segfault in getpwuid when stat fails
  [28815] libc: realpath should not copy to resolved buffer on error
  [28828] stdio: fputwc crashes
  [28838] libc: FAIL: elf/tst-p_align3
  [28845] locale: ld-monetary.c should be updated to match ISO C and
    other standards.
  [28850] libc: linux: __get_nprocs_sched reads uninitialized memory
    from the stack
  [28852] libc: getaddrinfo leaks memory with AI_ALL
  [28853] libc: tst-spawn6 changes current foreground process group
    (breaks test isolation)
  [28857] libc: FAIL: elf/tst-audit24a
  [28860] build: --enable-kernel=5.1.0 build fails because of missing
    __convert_scm_timestamps
  [28865] libc: linux: _SC_NPROCESSORS_CONF and _SC_NPROCESSORS_ONLN are
    inaccurate without /sys and /proc
  [28868] dynamic-link: Dynamic loader DFS algorithm segfaults on
    missing libraries
  [28880] libc: Program crashes if date beyond 2038
  [28883] libc: sysdeps/unix/sysv/linux/select.c: __select64
    !__ASSUME_TIME64_SYSCALLS && !__ASSUME_PSELECT fails on Microblaze
  [28896] string: strncmp-avx2-rtm and wcsncmp-avx2-rtm fallback on non-
    rtm variants when avoiding overflow
  [28922] build: The .d dependency files aren't always generated
  [28931] libc: hosts lookup broken for SUCCESS=CONTINUE and
    SUCCESS=MERGE
  [28936] build: nm: No such file
  [28950] localedata: Add locale for ISO code "tok" (Toki Pona)
  [28953] nss: NSS lookup result can be incorrect if function lookup
    clobbers errno
  [28970] math: benchtest: libmvec benchmark doesn't build with make
    bench.
  [28991] libc: sysconf(_SC_NPROCESSORS_CONF) should read
    /sys/devices/system/cpu/possible
  [28993] libc: closefrom() iterates until max int if no access to
    /proc/self/fd/
  [28996] libc: realpath fails to copy partial result to resolved buffer
    on ENOENT and EACCES
  [29027] math: [ia64] fabs fails with sNAN input
  [29029] nptl: poll() spuriously returns EINTR during thread
    cancellation and with cancellation disabled
  [29030] string: GLIBC 2.35 regression - Fortify crash on certain valid
    uses of mbsrtowcs (*** buffer overflow detected ***: terminated)
  [29062] dynamic-link: Memory leak in _dl_find_object_update if object
    is promoted to global scope
  [29069] libc: fstatat64_time64_statx wrapper broken on MIPS N32 with
    -D_FILE_OFFSET_BITS=64 and -D_TIME_BITS=64
  [29071] dynamic-link: m68k: Removal of ELF_DURING_STARTUP optimization
    broke ld.so
  [29097] time: fchmodat does not handle 64 bit time_t for
    AT_SYMLINK_NOFOLLOW
  [29109] libc: posix_spawn() always returns 1 (EPERM) on clone()
    failure
  [29141] libc: _FORTIFY_SOURCE=3 fail for gcc 12/glibc 2.35
  [29162] string: [PATCH] string.h syntactic error:
    include/bits/string_fortified.h:110: error: expected ',' or ';'
    before '__fortified_attr_access'
  [29165] libc: [Regression] broken argv adjustment
  [29187] dynamic-link: [regression] broken argv adjustment for nios2
  [29193] math: sincos produces a different output than sin/cos
  [29197] string: __strncpy_power9() uses uninitialised register vs18
    value for filling after \0
  [29203] libc: daemon is not y2038 aware
  [29204] libc: getusershell is not 2038 aware
  [29207] libc: posix_fallocate fallback implementation is not y2038
    aware
  [29208] libc: fpathconf(_PC_ASYNC_IO) is not y2038 aware
  [29209] libc: isfdtype is not y2038 aware
  [29210] network: ruserpass is not y2038 aware
  [29211] libc: __open_catalog is not y2038 aware
  [29213] libc: gconv_parseconfdir is not y2038 aware
  [29214] nptl: pthread_setcanceltype fails to set type
  [29225] network: Mistyped define statement in socket/sys/socket.h in
    line 184
  [29274] nptl: __read_chk is not a cancellation point
  [29279] libc: undefined reference to `mbstowcs_chk' after
    464d189b9622932a75302290625de84931656ec0
  [29304] libc: mq_timedreceive does not handle 64 bit syscall return
    correct for !__ASSUME_TIME64_SYSCALLS
  [29403] libc: st_atim, st_mtim, st_ctim stat struct members are
    missing on microblaze with largefile

Version 2.35

Major new features:

* Unicode 14.0.0 Support: Character encoding, character type info, and
  transliteration tables are all updated to Unicode 14.0.0, using
  generator scripts contributed by Mike FABIAN (Red Hat).

* Bump r_version in the debugger interface to 2 and add a new field,
  r_next, support multiple namespaces.

* Support for the C.UTF-8 locale has been added to glibc.  The locale
  supports full code-point sorting for all valid Unicode code points.  A
  limitation in the framework for fnmatch, regexec, and regcomp requires
  a compromise to save space and only ASCII-based range expressions are
  supported for now (see bug 28255).  The full size of the locale is
  only ~400KiB, with 346KiB coming from LC_CTYPE information for
  Unicode.  This locale harmonizes downstream C.UTF-8 already shipping
  in various downstream distributions.  The locale is not built into
  glibc, and must be installed.

* <math.h> functions that round their results to a narrower type, and
  corresponding <tgmath.h> macros, are added from TS 18661-1:2014, TS
  18661-3:2015 and draft ISO C2X:

  - fsqrt, fsqrtl, dsqrtl and corresponding fMsqrtfN, fMsqrtfNx,
    fMxsqrtfN and fMxsqrtfNx functions.

  - ffma, ffmal, dfmal and corresponding fMfmafN, fMfmafNx, fMxfmafN and
    fMxfmafNx functions.

* <math.h> functions for floating-point maximum and minimum,
  corresponding to new operations in IEEE 754-2019, and corresponding
  <tgmath.h> macros, are added from draft ISO C2X: fmaximum,
  fmaximum_num, fmaximum_mag, fmaximum_mag_num, fminimum, fminimum_num,
  fminimum_mag, fminimum_mag_num and corresponding functions for float,
  long double, _FloatN and _FloatNx.

* <math.h> macros for single-precision float constants are added as a
  GNU extension: M_Ef, M_LOG2Ef, M_LOG10Ef, M_LN2f, M_LN10f, M_PIf,
  M_PI_2f, M_PI_4f, M_1_PIf, M_2_PIf, M_2_SQRTPIf, M_SQRT2f and
  M_SQRT1_2f.

* The __STDC_IEC_60559_BFP__ and __STDC_IEC_60559_COMPLEX__ macros are
  predefined as specified in TS 18661-1:2014.

* The exp10 functions in <math.h> now have a corresponding type-generic
  macro in <tgmath.h>.

* The ISO C2X macro _PRINTF_NAN_LEN_MAX has been added to <stdio.h>.

* printf-family functions now support the %b format for output of
  integers in binary, as specified in draft ISO C2X, and the %B variant
  of that format recommended by draft ISO C2X.

* A new DSO sorting algorithm has been added in the dynamic linker that uses
  topological sorting by depth-first search (DFS), solving performance issues
  of the existing sorting algorithm when encountering particular circular
  object dependency cases.

* A new tunable, glibc.rtld.dynamic_sort, can be used to select between
  the two DSO sorting algorithms.  The default setting of '2' uses the
  new DFS-based algorithm.  The setting '1' switches to the old
  algorithm used in glibc 2.33 and earlier.

* ABI support for a new function '__memcmpeq'. '__memcmpeq' is meant
  to be used by compilers for optimizing usage of 'memcmp' when its
  return value is only used for its boolean status.

* Support for automatically registering threads with the Linux rseq
  system call has been added.  This system call is implemented starting
  from Linux 4.18.  The Restartable Sequences ABI accelerates user-space
  operations on per-cpu data.  It allows user-space to perform updates
  on per-cpu data without requiring heavy-weight atomic operations.
  Automatically registering threads allows all libraries, including
  libc, to make immediate use of the rseq support by using the
  documented ABI, via the __rseq_flags, __rseq_offset, and __rseq_size
  variables.  The GNU C Library manual has details on integration of
  Restartable Sequences.

* A symbolic link to the dynamic linker is now installed under
  /usr/bin/ld.so (or more precisely, '${bindir}/ld.so').

* All programs and the testsuite in glibc are now built as position independent
  executables (PIE) by default on toolchains and architectures that support it.
  Further, if the toolchain and architecture supports it, even static programs
  are built as PIE and the resultant glibc can be used to build static PIE
  executables.  A new option --disable-default-pie has been added to disable
  this behavior and get a non-PIE build.  This option replaces
  --enable-static-pie, which no longer has any effect on the build
  configuration.

* On Linux, a new tunable, glibc.malloc.hugetlb, can be used to
  either make malloc issue madvise plus MADV_HUGEPAGE on mmap and sbrk
  or to use huge pages directly with mmap calls with the MAP_HUGETLB
  flags).  The former can improve performance when Transparent Huge Pages
  is set to 'madvise' mode while the latter uses the system reserved
  huge pages.

* The printf family of functions now handles the flagged %#m conversion
  specifier, printing errno as an error constant (similar to strerrorname_np).

* The function _dl_find_object has been added.  In-process unwinders
  can use it to efficiently locate unwinding information for a code
  address.

* Support for OpenRISC running on Linux has been added.  This port requires
  as least binutils 2.35, GCC 11, and Linux 5.4.  Currently only soft-float
  ABI is supported:

    - or1k-linux-gnu

  The OpenRISC ABI is 32-bit big-endian and uses 64-bit time (y2038 safe) and
  64-bit file offsets (LFS default).

* A new configure option, --with-rtld-early-cflags, can be used to
  specify additional compiler flags for building the early startup code
  of the dynamic linker.  On targets which have CPU compatibility
  checks, this can help to ensure that proper diagnostics are printed if
  the dynamic loader runs on an incompatible CPU.

* On Linux, the epoll_pwait2 function has been added.  It is similar to
  epoll_wait with the difference the timeout has nanoseconds resolution.

* The function posix_spawn_file_actions_addtcsetpgrp_np has been added,
  enabling posix_spawn and posix_spawnp to set the controlling terminal in
  the new process in a race free manner.  This function is a GNU extension.

* Source fortification (_FORTIFY_SOURCE) level 3 is now available for
  applications compiling with glibc and gcc 12 and later. Level 3 leverages
  the __builtin_dynamic_object_size function to deliver additional
  fortification balanced against additional runtime cost (checking non-constant
  bounds).

* The audit libraries will avoid unnecessary slowdown if it is not required
  PLT tracking (by not implementing the la_pltenter or la_pltexit callbacks).

Deprecated and removed features, and other changes affecting compatibility:

* On x86-64, the LD_PREFER_MAP_32BIT_EXEC environment variable support
  has been removed since the first PT_LOAD segment is no longer executable
  due to defaulting to -z separate-code.

* The r_version update in the debugger interface makes the glibc binary
  incompatible with GDB binaries built without the following commits:

  c0154a4a21a gdb: Don't assume r_ldsomap when r_version > 1 on Linux
  4eb629d50d4 gdbserver: Check r_version < 1 for Linux debugger interface

  when audit modules or dlmopen are used.

* Intel MPX support (lazy PLT, ld.so profile, and LD_AUDIT) has been removed.

* The --enable-static-pie option is no longer available.  The glibc build
  configuration script now automatically detects static-pie support in the
  toolchain and architecture and enables it if available.

* The catchsegv script and associated libSegFault.so shared object have
  been removed.  There are widely-deployed out-of-process alternatives for
  catching coredumps and backtraces.

* Support for prelink will be removed in the next release; this includes
  removal of the LD_TRACE_PRELINKING, and LD_USE_LOAD_BIAS, environment
  variables and their functionality in the dynamic loader.

* The LD_TRACE_PRELINKING environment variable has been removed.  Similar
  functionality to obtain the program mapping address can be achieved by
  using LD_TRACE_LOADED_OBJECTS to value of 2.

* The LD_USE_LOAD_BIAS has been removed.  The variable was mainly used to
  support prelink PIE binaries.

Changes to build and runtime requirements:

* The audit module interface version LAV_CURRENT is increased to enable
  proper bind-now support.  The loader now advertises via the la_symbind
  flags that PLT trace is not possible.  New audit modules require the
  new dynamic loader supporting the latest LAV_CURRENT version. Old audit
  modules are still loaded for all targets except aarch64.

* The audit interface on aarch64 is extended to support both the indirect
  result location register (x8) and NEON Q register.  Old audit modules are
  rejected by the loader.  Audit modules must be rebuilt to use the newer
  structure sizes and the latest module interface version for LAV_CURRENT.

Security related changes:

  CVE-2022-23219: Passing an overlong file name to the clnt_create
  legacy function could result in a stack-based buffer overflow when
  using the "unix" protocol.  Reported by Martin Sebor.

  CVE-2022-23218: Passing an overlong file name to the svcunix_create
  legacy function could result in a stack-based buffer overflow.

  CVE-2021-3998: Passing a path longer than PATH_MAX to the realpath
  function could result in a memory leak and potential access of
  uninitialized memory.  Reported by Qualys.

  CVE-2021-3999: Passing a buffer of size exactly 1 byte to the getcwd
  function may result in an off-by-one buffer underflow and overflow
  when the current working directory is longer than PATH_MAX and also
  corresponds to the / directory through an unprivileged mount
  namespace.  Reported by Qualys.

The following bugs are resolved with this release:

  [12889] nptl: Race condition in pthread_kill
  [14232] nptl: tst-cancel7 and tst-cancelx7 race condition
  [14913] libc: [mips] Clean up MIPS 64-bit register-dump.h output
  [15310] dynamic-link: _dl_sort_fini is O(n^3) causing slow exit when
    many dsos
  [15333] libc: Use 64-bit stat functions in installed programs
  [15533] dynamic-link: LD_AUDIT introduces an avoidable performance
    degradation
  [15971] dynamic-link: No interface for debugger access to libraries
    loaded with dlmopen
  [17318] locale: [RFE] Provide a C.UTF-8 locale by default
  [17645] dynamic-link: RFE: Improve performance of dynamic loader for
    deeply nested DSO dependencies.
  [19193] nptl: pthread_kill, pthread_cancel return ESRCH for a thread
    ID whose lifetime has not ended
  [22542] network: buffer overflow in sunrpc clnt_create
    (CVE-2022-23219)
  [22716] malloc: [PATCH] mtrace.pl: use TRACE_PRELINKING instead of
    TRACE_LOADED_OBJECTS
  [25947] malloc: memory leak in muntrace
  [26045] math: fmaxf(inf, nan) does not always work
  [26108] math: exp10() has problems with <tgmath.h>
  [26779] build: benign use after realloc at localealias.c:329
  [27609] dynamic-link: [2.32/2.33/2.34 Regression] In elf/dl-open.c
    (_dl_open) we might use __LM_ID_CALLER to index GL(dl_ns)[]
  [27945] build: build-many-glibcs.py doesn't configure GCC with
    --enable-initfini-array
  [27991] build: x86: sysdeps/x86/configure.ac breaks when
    libc_cv_include_x86_isa_level is loaded from cache
  [28036] nptl: Incorrect types for pthread_mutexattr_set/getrobust_np
    in __REDIRECT_NTH macro
  [28061] dynamic-link: A failing dlmopen called by an auditor crashed
  [28062] dynamic-link: Suppress audit calls when a (new) namespace is
    empty
  [28126] libc: nftw aborts for paths longer than PATH_MAX
  [28129] dynamic-link: Unnecessary check DT_DEBUG in ld.so
  [28153] libc: [test] gmon/tst-gmon-gprof* may have a f3 line when
    built with ld.lld
  [28182] libc: _TIME_BITS=64 in C++ has issues with fcntl, ioctl, prctl
  [28185] math: Inaccurate j0f function (again)
  [28199] locale: iconvconfig prefix flag behaves differently in glibc
    2.34
  [28203] dynamic-link: aarch64: elf_machine_{load_address,dynamic}
    should drop _GLOBAL_OFFSET_TABLE_[0] in favor of __ehdr_start for
    robustness
  [28213] librt: NULL pointer dereference in mq_notify (CVE-2021-38604)
  [28223] libc: mips: clone does not align stack
  [28253] dynamic-link: Missing colon in LD_SHOW_AUXV output after
    AT_MINSIGSTKSZ
  [28256] malloc: Conditional jump or move depends on uninitialised
    value(s) in __GI___tunables_init
  [28260] build: io/tst-closefrom, misc/tst-close_range, posix/tst-
    spawn5 fail if stray fds are open
  [28310] libc: Do not use affinity mask for sysconf
    (_SC_NPROCESSORS_CONF)
  [28338] time: undefined behavior in __tzfile_compute with oddball TZif
    file
  [28340] dynamic-link: ld.so crashes while loading a DSO with a read-
    only dynamic section
  [28349] libc: Segfault for ping -R on qemux86 caused by recvmsg()
  [28350] libc: ping receives SIGABRT on lib32-qemux86-64 caused by
    recvmsg()
  [28353] network: Race condition on __opensock
  [28357] dynamic-link: deadlock between pthread_create and ctors
  [28358] math: f64xdivf128 and f64xmulf128 spurious underflows
  [28361] nptl: Fix for bug 12889 causes setxid deadlock
  [28368] build: -Waddress instances in stdio-common/vfprintf-internal.c
  [28390] localedata: Update locale data to Unicode 14.0.0
  [28397] math: tgmath.h should not define fmaxmag, fminmag macros for
    C2X
  [28400] libc: [2.35 Regression] string/test-strncasecmp: cannot set
    locale "en_US.UTF-8"
  [28407] nptl: pthread_kill assumes that kill (getpid ()) is equivalent
    to tgkill (getpid (), gettid())
  [28455] dynamic-link: -Wl,--enable-new-dtags doesn't work
  [28457] dynamic-link: Missing reldepmod4.so dependency for
    globalmod1.so
  [28469] time: linux: struct timex is not correctly set for 32-bit
    systems with TIMESIZE=64
  [28470] regex: Buffer read overrun in regular expression searching
  [28475] string: Incorrect access attribute on memfrob
  [28524] libc: Conversion from ISO-2022-JP-3 with iconv may emit
    spurious NUL character on state reset
  [28532] libc: powerpc64[le]: CFI for assembly templated syscalls is
    incorrect
  [28550] dynamic-link: FAIL: tst-dso-
    ordering9_112-ecbda(GLIBC_TUNABLES=glibc.rtld.dynamic_sort=1)
    execution test
  [28554] build: Undefined generate-md5
  [28572] libc: Misaligned accesses in test-memcpy and test-mempcpy on
    hppa
  [28607] nptl: Masked signals are delivered on thread exit
  [28624] libc: openjdk 8/9 assume uni processor and gets stuck due to
    lack of cpu counting /proc fallback with glibc 2.34
  [28646] string: [2.35 Regression] mock -r fedora-36-x86_64
    /tmp/java-1.8.0-openjdk-1.8.0.312.b07-2.fc36.src.rpm& fails to build
  [28648] dynamic-link: Running ld.so on statically linked binaries
    crashes
  [28656] dynamic-link: LD_PREFER_MAP_32BIT_EXEC no longer works due to
    binutils changes
  [28676] dynamic-link: p_align on PT_LOAD segment in DSO isn't honored
  [28678] nptl: nptl/tst-create1 hangs sporadically
  [28688] dynamic-link: PT_LOAD p_align check is too strict
  [28700] nss: "dns [!UNAVAIL=return] files" default for hosts database
    is not useful
  [28707] time: assert in tzfile.c __tzfile_read striking with truncated
    timezones generated by tzcode-2021d and later
  [28713] math: GCC 12 miscompiles libm
  [28732] dynamic-link: FAIL: elf/tst-dl_find_object
  [28738] build: LIBC_LINKER_FEATURE doesn't work on linker -z option
  [28745] dynamic-link: _dl_find_object miscompilation on powerpc64le
  [28746] libc: _FORTIFY_SOURCE does not work for stpcpy
  [28749] libc: Inconsistency detected by ld.so: rtld.c: 1632: dl_main:
    Assertion `GL(dl_rtld_map).l_libname' failed!
  [28755] string: overflow bug in wcsncmp_avx2 and wcsncmp_evex
  [28757] nptl: GDB printer tests failed with new GDB
  [28765] math: x86_64 libmvec atan2 accuracy
  [28766] manual: Document libmvec accuracy
  [28768] network: Buffer overflow in svcunix_create with long pathnames
    (CVE-2022-23218)
  [28769] libc: Off-by-one buffer overflow/underflow in getcwd()
    (CVE-2021-3999)
  [28770] libc: Unexpected return value from realpath() for too long
    results (CVE-2021-3998)
  [28771] libc: %ebx optimization macros are incompatible with .altmacro
    in Systemtap probes
  [28780] build: --disable-default-pie doesn't work on static programs
  [28782] libc: x86-64 ISA level for glibc itself is always
    x86-64-baseline
  [28792] glob: possible wrong behaviour with patterns with double [
    with no closing ]
  [28837] libc: FAIL: socket/tst-socket-timestamp-compat
  [28847] locale: Empty mon_decimal_point in LC_MONETARY results in non-
    empty mon_decimal_point_wc


Version 2.34

Major new features:

* In order to support smoother in-place-upgrades and to simplify
  the implementation of the runtime all functionality formerly
  implemented in the libraries libpthread, libdl, libutil, libanl has
  been integrated into libc.  New applications do not need to link with
  -lpthread, -ldl, -lutil, -lanl anymore.  For backwards compatibility,
  empty static archives libpthread.a, libdl.a, libutil.a, libanl.a are
  provided, so that the linker options keep working.  Applications which
  have been linked against glibc 2.33 or earlier continue to load the
  corresponding shared objects (which are now empty).  The integration
  of those libraries into libc means that additional symbols become
  available by default.  This can cause applications that contain weak
  references to take unexpected code paths that would only have been
  used in previous glibc versions when e.g. preloading libpthread.so.0,
  potentially exposing application bugs.

* When _DYNAMIC_STACK_SIZE_SOURCE or _GNU_SOURCE are defined,
  PTHREAD_STACK_MIN is no longer constant and is redefined to
  sysconf(_SC_THREAD_STACK_MIN).  This supports dynamic sized register
  sets for modern architectural features like Arm SVE.

* Add _SC_MINSIGSTKSZ and _SC_SIGSTKSZ.  When _DYNAMIC_STACK_SIZE_SOURCE
  or _GNU_SOURCE are defined, MINSIGSTKSZ and SIGSTKSZ are no longer
  constant on Linux.  MINSIGSTKSZ is redefined to sysconf(_SC_MINSIGSTKSZ)
  and SIGSTKSZ is redefined to sysconf (_SC_SIGSTKSZ).  This supports
  dynamic sized register sets for modern architectural features like
  Arm SVE.

* The dynamic linker implements the --list-diagnostics option, printing
  a dump of information related to IFUNC resolver operation and
  glibc-hwcaps subdirectory selection.

* On Linux, the function execveat has been added.  It operates similar to
  execve and it is is already used to implement fexecve without requiring
  /proc to be mounted.  However, different than fexecve, if the syscall is not
  supported by the kernel an error is returned instead of trying a fallback.

* The ISO C2X function timespec_getres has been added.

* The feature test macro __STDC_WANT_IEC_60559_EXT__, from draft ISO
  C2X, is supported to enable declarations of functions defined in Annex F
  of C2X.  Those declarations are also enabled when
  __STDC_WANT_IEC_60559_BFP_EXT__, as specified in TS 18661-1, is
  defined, and when _GNU_SOURCE is defined.

* On powerpc64*, glibc can now be compiled without scv support using the
  --disable-scv configure option.

* Add support for 64-bit time_t on configurations like x86 where time_t
  is traditionally 32-bit.  Although time_t still defaults to 32-bit on
  these configurations, this default may change in future versions.
  This is enabled with the _TIME_BITS preprocessor macro set to 64 and is
  only supported when LFS (_FILE_OFFSET_BITS=64) is also enabled.  It is
  only enabled for Linux and the full support requires a minimum kernel
  version of 5.1.

* The main gconv-modules file in glibc now contains only a small set of
  essential converter modules and the rest have been moved into a supplementary
  configuration file gconv-modules-extra.conf in the gconv-modules.d directory
  in the same GCONV_PATH.  Similarly, external converter modules directories
  may have supplementary configuration files in a gconv-modules.d directory
  with names ending with .conf to logically classify the converter modules in
  that directory.

* On Linux, a new tunable, glibc.pthread.stack_cache_size, can be used
  to configure the size of the thread stack cache.

* The function _Fork has been added as an async-signal-safe fork replacement
  since Austin Group issue 62 dropped the async-signal-safe requirement for
  fork (and it will be included in the future POSIX standard).  The new _Fork
  function does not run any atfork function neither resets any internal state
  or lock (such as the malloc one), and only sets up a minimal state required
  to call async-signal-safe functions (such as raise or execve).  This function
  is currently a GNU extension.

* On Linux, the close_range function has been added.  It allows efficiently
  closing a range of file descriptors on recent kernels (version 5.9).

* The function closefrom has been added.  It closes all file descriptors
  greater than or equal to a given integer.  This function is a GNU extension,
  although it is also present in other systems.

* The posix_spawn_file_actions_addclosefrom_np function has been added,
  enabling posix_spawn and posix_spawnp to close all file descriptors greater
  than or equal to a given integer.  This function is a GNU extension,
  although Solaris also provides a similar function.

* When invoked explicitly, the dynamic linker now uses the kernel to
  execute programs that do not have any dynamic dependency (that is,
  they are statically linked).  This feature is Linux-specific.

Deprecated and removed features, and other changes affecting compatibility:

* The function pthread_mutex_consistent_np has been deprecated; programs
  should use the equivalent standard function pthread_mutex_consistent
  instead.

* The function pthread_mutexattr_getrobust_np has been deprecated;
  programs should use the equivalent standard function
  pthread_mutexattr_getrobust instead.

* The function pthread_mutexattr_setrobust_np has been deprecated;
  programs should use the equivalent standard function
  pthread_mutexattr_setrobust instead.

* The function pthread_yield has been deprecated; programs should use
  the equivalent standard function sched_yield instead.

* The function inet_neta declared in <arpa/inet.h> has been deprecated.

* Various rarely-used functions declared in <resolv.h> and
  <arpa/nameser.h> have been deprecated.  Applications are encouraged to
  use dedicated DNS processing libraries if applicable.  For <resolv.h>,
  this affects the functions dn_count_labels, fp_nquery, fp_query,
  fp_resstat, hostalias, loc_aton, loc_ntoa, p_cdname, p_cdnname,
  p_class, p_fqname, p_fqnname, p_option, p_query, p_rcode, p_time,
  p_type, putlong, putshort, res_hostalias, res_isourserver,
  res_nameinquery, res_queriesmatch, res_randomid, sym_ntop, sym_ntos,
  sym_ston.  For <arpa/nameser.h>, the functions ns_datetosecs,
  ns_format_ttl, ns_makecanon, ns_parse_ttl, ns_samedomain, ns_samename,
  ns_sprintrr, ns_sprintrrf, ns_subdomain have been deprecated.

* Various symbols previously defined in libresolv have been moved to libc
  in order to prepare for libresolv moving entirely into libc (see earlier
  entry for merging libraries into libc).  The symbols __dn_comp,
  __dn_expand, __dn_skipname, __res_dnok, __res_hnok, __res_mailok,
  __res_mkquery, __res_nmkquery, __res_nquery, __res_nquerydomain,
  __res_nsearch, __res_nsend, __res_ownok, __res_query, __res_querydomain,
  __res_search, __res_send formerly in libresolv have been renamed and no
  longer have a __ prefix.  They are now available in libc.

* The pthread cancellation handler is now installed with SA_RESTART and
  pthread_cancel will always send the internal SIGCANCEL on a cancellation
  request.  It should not be visible to applications since the cancellation
  handler should either act upon cancellation (if asynchronous cancellation
  is enabled) or ignore the cancellation internal signal.  However there are
  buggy kernel interfaces (for instance some CIFS versions) that could still
  see a spurious EINTR error when cancellation interrupts a blocking syscall.

* Previously, glibc installed its various shared objects under versioned
  file names such as libc-2.33.so.  The ABI sonames (e.g., libc.so.6)
  were provided as symbolic links.  Starting with glibc 2.34, the shared
  objects are installed under their ABI sonames directly, without
  symbolic links.  This increases compatibility with distribution
  package managers that delete removed files late during the package
  upgrade or downgrade process.

* The symbols mallwatch and tr_break are now deprecated and no longer used in
  mtrace.  Similar functionality can be achieved by using conditional
  breakpoints within mtrace functions from within gdb.

* The __morecore and __after_morecore_hook malloc hooks and the default
  implementation __default_morecore have been removed from the API.  Existing
  applications will continue to link against these symbols but the interfaces
  no longer have any effect on malloc.

* Debugging features in malloc such as the MALLOC_CHECK_ environment variable
  (or the glibc.malloc.check tunable), mtrace() and mcheck() have now been
  disabled by default in the main C library.  Users looking to use these
  features now need to preload a new debugging DSO libc_malloc_debug.so to get
  this functionality back.

* The deprecated functions malloc_get_state and malloc_set_state have been
  moved from the core C library into libc_malloc_debug.so.  Legacy applications
  that still use these functions will now need to preload libc_malloc_debug.so
  in their environment using the LD_PRELOAD environment variable.

* The deprecated memory allocation hooks __malloc_hook, __realloc_hook,
  __memalign_hook and __free_hook are now removed from the API.  Compatibility
  symbols are present to support legacy programs but new applications can no
  longer link to these symbols.  These hooks no longer have any effect on glibc
  functionality.  The malloc debugging DSO libc_malloc_debug.so currently
  supports hooks and can be preloaded to get this functionality back for older
  programs.  However this is a transitional measure and may be removed in a
  future release of the GNU C Library.  Users may port away from these hooks by
  writing and preloading their own malloc interposition library.

Changes to build and runtime requirements:

* On Linux, the shm_open, sem_open, and related functions now expect the
  file shared memory file system to be mounted at /dev/shm.  These functions
  no longer search among the system's mount points for a suitable
  replacement if /dev/shm is not available.

Security related changes:

  CVE-2021-27645: The nameserver caching daemon (nscd), when processing
  a request for netgroup lookup, may crash due to a double-free,
  potentially resulting in degraded service or Denial of Service on the
  local system.  Reported by Chris Schanzle.

  CVE-2021-33574: The mq_notify function has a potential use-after-free
  issue when using a notification type of SIGEV_THREAD and a thread
  attribute with a non-default affinity mask.

  CVE-2021-35942: The wordexp function may overflow the positional
  parameter number when processing the expansion resulting in a crash.
  Reported by Philippe Antoine.

The following bugs are resolved with this release:

  [4737] libc: fork is not async-signal-safe
  [5781] math: Slow dbl-64 sin/cos/sincos for special values
  [10353] libc: Methods for deleting all file descriptors greater than
    given integer (closefrom)
  [14185] glob: fnmatch() fails when '*' wildcard is applied on the file
    name containing multi-byte character(s)
  [14469] math: Inaccurate j0f function
  [14470] math: Inaccurate j1f function
  [14471] math: Inaccurate y0f function
  [14472] math: Inaccurate y1f function
  [14744] nptl: kill -32 $pid or kill -33 $pid on a process cancels a
    random thread
  [15271] dynamic-link: dlmopen()ed shared library with LM_ID_NEWLM
    crashes if it fails dlsym() twice
  [15648] nptl: multiple definition of `__lll_lock_wait_private'
  [16063] nptl: Provide a pthread_once variant in libc directly
  [17144] libc: syslog is not thread-safe if NO_SIGPIPE is not defined
  [17145] libc: syslog with LOG_CONS leaks console file descriptor
  [17183] manual: description of ENTRY struct in <search.h> in glibc
    manual is incorrect
  [18435] nptl: pthread_once hangs when init routine throws an exception
  [18524] nptl: Missing calloc error checking in
    __cxa_thread_atexit_impl
  [19329] dynamic-link: dl-tls.c assert failure at concurrent
    pthread_create and dlopen
  [19366] nptl: returning from a thread should disable cancellation
  [19511] nptl: 8MB memory leak in pthread_create in case of failure
    when non-root user changes priority
  [20802] dynamic-link: getauxval NULL pointer dereference after static
    dlopen
  [20813] nptl: pthread_exit is inconsistent between libc and libpthread
