GNU C Library NEWS -- history of user-visible changes.
Copyright (C) 1992-2025 Free Software Foundation, Inc.
See the end for copying conditions.

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Version 2.41

Major new features:

* Support for testing a glibc build with a set of C and C++ compilers
  different from the C and C++ compilers used to build glibc has been
  added:
  $ ../configure TEST_CC="gcc-6.4.1" TEST_CXX="g++-6.4.1"

  This includes support for testing the glibc build with Clang, e.g.,
  $ ../configure TEST_CC="clang" TEST_CXX="clang++"

  Some run-time failures with Clang are expected.

* The glibc test suite has been extended again significantly, with now
  6232 separate tests compared to 5408 in glibc-2.40.

* In /etc/resolv.conf and the RES_OPTIONS environment variable, option
  flags can now be prefixed with “-” to clear previously set flags.
  For example, if /etc/resolv.conf contains “options no-aaaa”, a
  process running with the RES_OPTIONS=-no-aaaa environment variable
  performs AAAA DNS queries when the glibc DNS stub resolver is used.

* The DNS stub resolver now supports the strict-error option.  If
  activated, getaddrinfo for the AF_UNSPEC address family (with dual
  A/AAAA DNS lookups) attemps to obtain an A/AAAA response pair from
  another DNS server if one of the responses indicates failure.  Without
  the strict-error option, getaddrinfo returns the A record data it has
  obtained even if the AAAA query failed.  The new strict error mode is
  incompatible with some DNS environments which do not follow the RFCs,
  which is why this mode is not enabled by default.  A future version
  of the library may turn it on by default, however.

* On Linux, the sched_setattr and sched_getattr functions have been
  added, for supporting parameterized scheduling policies such as
  SCHED_DEADLINE.

* The iconv program now supports converting files in place.  The program
  automatically uses a temporary file if required.

* Character encoding, character type info, and transliteration tables
  have been updated to Unicode 16.0.0.

* The following ISO C23 function families (introduced in TS
  18661-4:2015) are now supported in <math.h>.  Each family includes
  functions for float, double, long double, _FloatN and _FloatNx, and a
  type-generic macro in <tgmath.h>.

  - Trigonometric functions: acospi, asinpi, atan2pi, atanpi, cospi,
    sinpi, tanpi.

* The GNU C Library now supports a feature test macro _ISOC2Y_SOURCE to
  enable features from the draft ISO C2Y standard.  Only some features
  from this draft standard are supported by the GNU C Library, and as
  the draft is under active development, the set of features enabled by
  this macro is liable to change.  Features from C2Y are also enabled
  by _GNU_SOURCE, or by compiling with "gcc -std=gnu2y".

* Optimized and correctly rounded exp10m1f, exp2m1f, expm1f, log10f,
  log2p1f, log1pf, log10p1f, cbrtf, erff, erfcf, lgammaf, tgammaf,
  tanf, acosf, acoshf, asinf, asinhf, atanf, atan2f, atanhf, coshf,
  sinhf, and tanhf functions have been added from the CORE-MATH
  project <https://core-math.gitlabpages.inria.fr/>.

* A benchtest framework is now in place to track the performance of many
  (mostly numerical) functions.

* A new tunable, glibc.rtld.execstack, can be used to control whether an
  executable stack is allowed from the main program, either implicitly
  due to a mising GNU_STACK ELF header or explicit explicitly because
  of the executable bit in GNU_STACK.  The default is to allow
  executable stacks.

* Support for the extensible rseq ABI introduced in the Linux kernel
  version 6.3 has been added.  The size and alignment of the rseq area
  is now determined by auxiliary vector entries when provided by the
  running kernel.  This results in __rseq_size now exposing features
  past the original ABI which currently include 'node_id' and 'mm_cid'
  and will also allow exposing new features as they get added to future
  Linux kernels.

* The GNU C Library now supports the Guarded Control Stack extension
  that allows to use shadow stacks on AArch64 systems that support this
  extension.  Building the library with standard branch protection
  enabled while using a toolchain that supports GCS (binutils 2.44 and
  GCC 15 or later) will enable GCS support in glibc.  There is no
  special configuration flag.  GCS-enabled glibc is compatible with all
  existing executables and shared libraries and will run with and
  without GCS support in the system.  GCS is opt-in and can be
  controlled at runtime via the glibc.cpu.aarch64_gcs tunable. By
  default GCS is disabled.  Linux kernel supports this since 6.13.

* Significant effort has been put into improving the code generation
  and speed of mathematical functions in the vector mathematics library
  on AArch64, with regard to the Scalable Vector Extension (SVE) and
  Advanced SIMD (Neon) intrinsics.

* Support for memory protection keys on AArch64 systems with enabled
  Stage 1 permission overlays feature as introduced in Armv8.9 / 9.4
  has been added.

* On PowerPC64, support for the return-oriented programming protection
  instructions added in ISA 3.1 (Power10) has been added, as well as
  function optimizations for Power10.

* A new architecture type has been introduced internally to better
  support Hygon x86-64 processors.

Deprecated and removed features, and other changes affecting
compatibility:

* abort is now async-signal-safe and its implementation makes longjmp
  from the SIGABRT handler always abort if set up with setjmp.  Use
  sigsetjmp to keep the old behavior, where the handler does not stop
  the process execution.

* dlopen and dlmopen no longer make the stack executable if a shared
  library requires it, either implicitly because of a missing GNU_STACK
  ELF header (and default ABI permission having the executable bit set)
  or explicitly because of the executable bit in GNU_STACK, and the
  stack is not already executable.  Instead, loading such objects will
  fail.

* The nios2*-*-linux-gnu configurations are no longer supported.

* The big-endian ARC port (arceb-linux-gnu) has been removed.

Changes to build and runtime requirements:

* On recent Linux kernels with vDSO getrandom support, getrandom does
  not act as a "shall occur" cancellation point, in which case it might
  not issue a syscall or trigger a deferred cancellation event.

* Testing the GNU C Library requires GNU awk to be compiled with support
  for high precision arithmetic via the MPFR library.

Security related changes:

The following CVEs were fixed in this release, details of which can be
found in the advisories directory of the release tarball:

  GLIBC-SA-2025-0001:
    assert: Buffer overflow when printing assertion failure message
    (CVE-2025-0395)

The following bugs were resolved with this release:

  [6050] locale: iconv(1) buffers all of stdin in memory
  [10460] locale: iconv does not support in-place conversion
  [12683] nptl: Race conditions in pthread cancellation
  [14147] nptl: Async cancellation left active after longjmp out of
    signal handler
  [14799] network: RES_OPTIONS cannot disable options enabled in
    /etc/resolv.conf
  [17703] locale: iconv(1) EFAULTs reading the second non-mmapable input
  [20632] stdio: Buffer overflow in wchar IO (_IO_wfile_overflow)
  [23675] stdio: freopen() with "ccs=<charset>" leaves the stream
    unoriented
  [25847] nptl: pthread_cond_signal failed to wake up pthread_cond_wait
    due to a bug in undoing stealing
  [26275] libc: abort(3) is not signal-safe
  [27543] ports: Inconsistent behavior when handling FPSCR on SH
  [27821] stdio: double call to ungetc causes uninitialized memory
    reading. (also: ungetc causes memory leak)
  [29437] libc: arc4random is too slow
  [30009] build: unterminated options list in benchtest
  [30081] network: libresolv: timeout when running in single-request
    mode
  [30220] math: String to double returns incorrectly rounded value for
    hexadecimal subnormal
  [30584] libc: initstate and initstate_r crash when the state argument
    is unaligned
  [30647] stdio: scanf functions wrong on nan()
  [31394] libc: clone on sparc might fail with -EFAULT for no valid
    reason
  [31717] dynamic-link: TLS for library gets reallocated when loaded in
    two contexts.
  [31799] dynamic-link: -static-pie -Wl,-Ttext-segment=0x50000 doesn't
    work
  [31859] locale: Transliteration rules with two input characters like
    "ḌḌ" "DDH" do not work.
  [31890] network: DNS stub resolver ignores header-only error responses
  [31928] build: glibc doesn't compile if the compiler already define
    _FORTIFY_SOURCE
  [31968] libc: mremap implementation in C does not handle arguments
    correctly
  [31985] dynamic-link: la_objopen not called when ld.so is imported
    into a private namespace. However, la_objclose is called with an
    unknown cookie.
  [31997] libc: exit is not thread-safe, even when all atexit handlers
    are thread-safe
  [32026] libc: strerror, strsignal TLS not handled correctly for
    secondary namespaces (dlmopen, LD_AUDIT)
  [32033] locale: iconv (the program) does not truncate output file if
    input is empty
  [32040] nptl: CPU affinity test skeleton for sched_setaffinity and
    pthread_setaffinity_np can fail to report failure.
  [32042] build: Compilation issue for tst-resolv-short-response.c with
    older GCC
  [32045] math: nan() / strtod() incorrectly set errno for overflowing
    nan payload
  [32046] locale: iconv -c fails to report input encoding errors if
    output buffer is full
  [32047] libc: Tunables may incorrectly set Prefer_PMINUB_for_stringop
  [32050] locale: iconv - - < /dev/null fails with Bad file descriptor
  [32052] libc: stdlib.h's use of 'sz' identifier causes libstdc++ test
    failure
  [32065] dynamic-link: _dl_fini does not call la_objclose for proxy
    link maps
  [32066] dynamic-link: dlclose signals la_activity (LA_ACT_DELETE)
    after la_objclose calls
  [32078] string: Random __strchrnul_evex512 failures
  [32124] libc: readdir_r does not relay errors reported by the kernel
  [32125] libc: powerpc: Missing TOC stub in __syscall_cancel_arch for
    powerpc64le-linux-gnu
  [32126] libc: readdir64_r: Do not skip entries with zero d_ino values
  [32128] libc: Compat readdir64_r (__old_readdir64_r) does not enforce
    NAME_MAX limit
  [32134] stdio: freopen does not clear flags2 (FD_CLOEXEC etc)
  [32137] libc: libio/tst-stderr-compat, libio/tst-bz24228, math/test-
    matherr-2, nptl/tst-pthread_kill-exited fails on powerpc-unknown-
    linux-gnu
  [32140] stdio: freopen leaks memory on failure
  [32145] libc: New stdlib/tst-strtod1i, stdlib/tst-strtod3, stdlib/tst-
    strtod4, stdlib/tst-strtod5i failures on powerpc64le-linux-gnu
  [32148] stdio: Memory corruption with ancient i386 binaries using
    stdio
  [32168] localedata: Update locale data to Unicode 16.0.0
  [32173] libc: sparc: restartable syscalls are broken
  [32192] build: s390: utf16-utf32-z9.c fails to build w/ -fomit-frame-
    pointer
  [32197] locale: FAIL: iconv/tst-iconv_prog-buffer failures
  [32212] string: x86_64/strcmp caused 25% performance drop by commit
    84e7c46df
  [32214] libc: random_bits always returns the same value if getrandom
    fails
  [32215] libc: Signal handlers after fork may encounter missing robust
    mutex list
  [32228] libc: .preinit_array in /lib/riscv64-linux-gnu/Scrt1.o is not
    properly aligned
  [32231] dynamic-link: ldconfig auxcache format change in 2.36
  [32233] libc: error calls va_end twice.
  [32234] hurd: missing va_end call in fcntl.c
  [32245] build: glibc -Wstringop-overflow= build failure on hppa
  [32280] localedata: Enable transliteration rules with two input
    characters in scn_IT
  [32283] libc: Compilation issue for tst-syscall-restart.c with GCC
    10.2.1
  [32323] localedata: eo: Incorrect first day of week and first week of
    year
  [32344] string: Assembler warnings when building strcpy-evex.S and
    strncpy-evex.S
  [32350] hurd: function __xpg_strerror_r crashes for specific arguments
  [32360] stdio: Compilation issue for tst-printf-format-skeleton.c with
    GCC 10.2.1
  [32366] malloc: malloc test failures with GCC 15
  [32380] locale: dcigettext can cause SIGSEGV when domain name is too
    long
  [32414] libc: [x86_64 regression] tst-strtod5i.c:124:(.text+0x47c):
    undefined reference to `__copysignf128'
  [32418] math: __XXX math functions are declared, but not provided
  [32420] build: GCC 6 can't build glibc 2.41
  [32440] libc: getrandom() in glibc 2.41 (development) returns EINVAL
    as retcode instead of errno on powerpc64le
  [32448] libc: iconv reports failure with successful transliteration
  [32450] libc: system() does not return -1 if a child process can't be
    created
  [32465] nss: ./getaddrinfo.c:1884:11: error: variable 'endp' is used
    uninitialized whenever '||' condition is true [-Werror,-Wsometimes-
    uninitialized]
  [32470] dynamic-link: Integer truncation during x86-64 cache size
    computation
  [32488] libc: Glibc failed to build with CET enabled
  [32492] libc: New test failures
  [32494] build: Compilation issue with GCC 14.2.1
  [32508] dynamic-link: ldd: /lib/ld-linux.so.2: cannot execute binary
    file: Exec format error
  [32512] dynamic-link: failure to build on loong, undefined reference
    to `stpcpy'
  [32543] build: x32 glibc is miscompiled
  [32588] libc: [2.41 regression] bash crashes with 'realloc(): invalid
    pointer' with `env -i PATH=`

Version 2.40

Major new features:

* The <stdbit.h> header type-generic macros have been changed when using
  GCC 14.1 or later to use __builtin_stdc_bit_ceil etc. built-in functions
  in order to support unsigned __int128 and/or unsigned _BitInt(N) operands
  with arbitrary precisions when supported by the target.

* The GNU C Library now supports a feature test macro _ISOC23_SOURCE to
  enable features from the ISO C23 standard.  Only some features from
  this standard are supported by the GNU C Library.  The older name
  _ISOC2X_SOURCE is still supported.  Features from C23 are also enabled
  by _GNU_SOURCE, or by compiling with the GCC options -std=c23,
  -std=gnu23, -std=c2x or -std=gnu2x.

* The following ISO C23 function families (introduced in TS
  18661-4:2015) are now supported in <math.h>.  Each family includes
  functions for float, double, long double, _FloatN and _FloatNx, and a
  type-generic macro in <tgmath.h>.

  - Exponential functions: exp2m1, exp10m1.

  - Logarithmic functions: log2p1, log10p1, logp1.

* A new tunable, glibc.rtld.enable_secure, can be used to run a program
  as if it were a setuid process. This is currently a testing tool to allow
  more extensive verification tests for AT_SECURE programs and not meant to
  be a security feature.

* On Linux, the epoll header was updated to include epoll ioctl definitions
  and the related structure added in Linux kernel 6.9.

* The fortify functionality has been significantly enhanced for building
  programs with clang against the GNU C Library.

* Many functions have been added to the vector library for aarch64:
    acosh, asinh, atanh, cbrt, cosh, erf, erfc, hypot, pow, sinh, tanh

* On x86, memset can now use non-temporal stores to improve the performance
  of large writes. This behaviour is controlled by a new tunable
  x86_memset_non_temporal_threshold.

Deprecated and removed features, and other changes affecting compatibility:

* Architectures which use a 32-bit seconds-since-epoch field in struct
  lastlog, struct utmp, struct utmpx (such as i386, powerpc64le, rv32,
  rv64, x86-64) switched from a signed to an unsigned type for that
  field.  This allows these fields to store timestamps beyond the year
  2038, until the year 2106.  Please note that applications are still
  expected to migrate off the interfaces declared in <utmp.h> and
  <utmpx.h> (except for login_tty) due to locking and session management
  problems.

* __rseq_size now denotes the size of the active rseq area (20 bytes
  initially), not the size of struct rseq (32 bytes initially).

Security related changes:

The following CVEs were fixed in this release, details of which can be
found in the advisories directory of the release tarball:

  GLIBC-SA-2024-0004:
    ISO-2022-CN-EXT: fix out-of-bound writes when writing escape
    sequence (CVE-2024-2961)

  GLIBC-SA-2024-0005:
    nscd: Stack-based buffer overflow in netgroup cache (CVE-2024-33599)

  GLIBC-SA-2024-0006:
    nscd: Null pointer crash after notfound response (CVE-2024-33600)

  GLIBC-SA-2024-0007:
    nscd: netgroup cache may terminate daemon on memory allocation
    failure (CVE-2024-33601)

  GLIBC-SA-2024-0008:
    nscd: netgroup cache assumes NSS callback uses in-buffer strings
    (CVE-2024-33602)

The following bugs are resolved with this release:

  [19622] network: Support aliasing with struct sockaddr
  [21271] localedata: cv_RU: update translations
  [23774] localedata: lv_LV collates Y/y incorrectly
  [23865] string: wcsstr is quadratic-time
  [25119] localedata: Change Czech weekday names to lowercase
  [27777] stdio: fclose does a linear search, takes ages when many FILE*
    are opened
  [29770] libc: prctl does not match manual page ABI on powerpc64le-
    linux-gnu
  [29845] localedata: Update hr_HR locale currency to €
  [30701] time: getutxent misbehaves on 32-bit x86 when _TIME_BITS=64
  [31316] build: Fails test misc/tst-dirname "Didn't expect signal from
    child: got `Illegal instruction'" on non SSE CPUs
  [31317] dynamic-link: [RISCV] static PIE crashes during self
    relocation
  [31325] libc: mips: clone3 is wrong for o32
  [31335] math: Compile glibc with -march=x86-64-v3 should disable FMA4
    multi-arch version
  [31339] libc: arm32 loader crash after cleanup in 2.36
  [31340] manual: A bad sentence in section 22.3.5 (resource.texi)
  [31357] dynamic-link: $(objpfx)tst-rtld-list-diagnostics.out rule
    doesn't work with test wrapper
  [31370] localedata: wcwidth() does not treat
    DEFAULT_IGNORABLE_CODE_POINTs as zero-width
  [31371] dynamic-link: x86-64: APX and Tile registers aren't preserved
    in ld.so trampoline
  [31372] dynamic-link: _dl_tlsdesc_dynamic doesn't preserve all caller-
    saved registers
  [31383] libc: _FORTIFY_SOURCE=3 and __fortified_attr_access vs size of
    0 and zero size types
  [31385] build: sort-makefile-lines.py doesn't check variable with _
    nor with "^# variable"
  [31402] libc: clone (NULL, NULL, ...) clobbers %r7 register on
    s390{,x}
  [31405] libc: Improve dl_iterate_phdr using _dl_find_object
  [31411] localedata: Add Latgalian locale
  [31412] build: GCC 6 failed to build i386 glibc on Fedora 39
  [31429] build: Glibc failed to build with -march=x86-64-v3
  [31468] libc: sigisemptyset returns true when the set contains signals
    larger than 34
  [31476] network: Automatic activation of single-request options break
    resolv.conf reloading
  [31479] libc: Missing #include <sys/rseq.h> in sched_getcpu.c may
    result in a loss of rseq acceleration
  [31501] dynamic-link: _dl_tlsdesc_dynamic_xsavec may clobber %rbx
  [31518] manual: documentation: FLT_MAX_10_EXP questionable text, evtl.
    wrong,
  [31530] localedata: Locale file for Moksha - mdf_RU
  [31553] malloc: elf/tst-decorate-maps fails on ppc64el
  [31596] libc: On the llvm-arm32 platform, dlopen("not_exist.so", -1)
    triggers segmentation fault
  [31600] math: math: x86 ceill traps when FE_INEXACT is enabled
  [31601] math: math: x86 floor traps when FE_INEXACT is enabled
  [31603] math: math: x86 trunc traps when FE_INEXACT is enabled
  [31612] libc: arc4random fails to fallback to /dev/urandom if
    getrandom is not present
  [31629] build: powerpc64: Configuring with "--with-cpu=power10" and
    'CFLAGS=-O2 -mcpu=power9' fails to build glibc
  [31640] dynamic-link: POWER10 ld.so crashes in
    elf_machine_load_address with GCC 14
  [31661] libc: NPROCESSORS_CONF and NPROCESSORS_ONLN not available in
    getconf
  [31676] dynamic-link: Configuring with CC="gcc -march=x86-64-v3"
    --with-rtld-early-cflags=-march=x86-64 results in linker failure
  [31677] nscd: nscd: netgroup cache: invalid memcpy under low
    memory/storage conditions
  [31678] nscd: nscd: Null pointer dereferences after failed netgroup
    cache insertion
  [31679] nscd: nscd: netgroup cache may terminate daemon on memory
    allocation failure
  [31680] nscd: nscd: netgroup cache assumes NSS callback uses in-buffer
    strings
  [31682] math: [PowerPC] Floating point exception error for math test
    test-ceil-except-2 test-floor-except-2 test-trunc-except-2
  [31686] dynamic-link: Stack-based buffer overflow in
    parse_tunables_string
  [31695] libc: pidfd_spawn/pidfd_spawnp leak an fd if clone3 succeeds
    but execve fails
  [31719] dynamic-link: --enable-hardcoded-path-in-tests doesn't work
    with -Wl,--enable-new-dtags
  [31730] libc: backtrace_symbols_fd prints different strings than
    backtrace_symbols returns
  [31753] build: FAIL: link-static-libc with GCC 6/7/8
  [31755] libc: procutils_read_file doesn't start with a leading
    underscore
  [31756] libc: write_profiling is only in libc.a
  [31757] build: Should XXXf128_do_not_use functions be excluded?
  [31759] math: Extra nearbyint symbols in libm.a
  [31760] math: Missing math functions
  [31764] build: _res_opcodes should be a compat symbol only
  [31765] dynamic-link: _dl_mcount_wrapper is exported without prototype
  [31766] stdio: _IO_stderr_ _IO_stdin_ _IO_stdout should be compat
    symbols
  [31768] string: Extra stpncpy symbol in libc.a
  [31770] libc: clone3 is in libc.a
  [31774] libc: Missing __isnanf128 in libc.a
  [31775] math: Missing exp10 exp10f32x exp10f64 fmod fmodf fmodf32
    fmodf32x fmodf64 in libm.a
  [31777] string: Extra memchr strlen symbols in libc.a
  [31781] math: Missing math functions in libm.a
  [31782] build: Test build failure with recent GCC trunk (x86/tst-cpu-
    features-supports.c:69:3: error: parameter to builtin not valid:
    avx5124fmaps)
  [31785] string: loongarch: Extra strnlen symbols in libc.a
  [31786] string: powerpc: Extra strchrnul and strncasecmp_l symbols in
    libc.a
  [31787] math: powerpc: Extra llrintf, llrintf, llrintf32, and
    llrintf32 symbols in libc.a
  [31788] libc: microblaze: Extra cacheflush symbol in libc.a
  [31789] libc: powerpc: Extra versionsort symbol in libc.a
  [31790] libc: s390: Extra getutent32, getutent32_r, getutid32,
    getutid32_r, getutline32, getutline32_r, getutmp32, getutmpx32,
    getutxent32, getutxid32, getutxline32, pututline32, pututxline32,
    updwtmp32, updwtmpx32 in libc.a
  [31797] build: g++ -static requirement should be able to opt-out
  [31798] libc: pidfd_getpid.c is miscompiled by GCC 6.4
  [31802] time: difftime is pure not const
  [31808] time: The supported time_t range is not documented.
  [31840] stdio: Memory leak in _IO_new_fdopen (fdopen) on seek failure
  [31867] build: "CPU ISA level is lower than required" on SSE2-free
    CPUs
  [31876] time: "Date and time" documentation fixes for POSIX.1-2024 etc
  [31883] build: ISA level support configure check relies on bashism /
    is otherwise broken for arithmetic
  [31892] build: Always install mtrace.
  [31917] libc: clang mq_open fortify wrapper does not handle 4 argument
    correctly
  [31927] libc: clang open fortify wrapper does not handle argument
    correctly
  [31931] time: tzset may fault on very short TZ string
  [31934] string: wcsncmp crash on s390x on vlbb instruction
  [31963] stdio: Crash in _IO_link_in within __gcov_exit
  [31965] dynamic-link: rseq extension mechanism does not work as
    intended
  [31980] build: elf/tst-tunables-enable_secure-env fails on ppc

Version 2.39

Major new features:

* A new tunable, glibc.cpu.plt_rewrite, can be used to enable PLT
  rewrite on x86-64.  When enabled with non-lazy binding, the dynamic
  linker will rewrite indirect branches in PLT with direct branches.

* Sync with Linux kernel 6.6 shadow stack interface.  The --enable-cet
  configure option is only supported on x86-64.

* struct statvfs now has an f_type member, equal to the f_type statfs member;
  on the Hurd this was always available under a reserved name,
  and under Linux a spare has been allocated: it was always zero
  in previous versions of glibc, and zero is not a valid result.

* On Linux, the functions posix_spawnattr_getcgroup_np and
  posix_spawnattr_setcgroup_np have been added, along with the
  POSIX_SPAWN_SETCGROUP flag.  They allow posix_spawn and posix_spawnp
  to set the cgroupv2 in the new process in a race-free manner.  These
  functions are GNU extensions and require a kernel with clone3 support.

* On Linux, the pidfd_spawn and pidfd_spawp functions have been added.
  They have a similar prototype and semantic as posix_spawn, but instead of
  returning a process ID, they return a file descriptor that can be used
  along other pidfd functions (like pidfd_send_signal, poll, or waitid).
  The pidfd functionality avoids the issue of PID reuse with the traditional
  posix_spawn interface.

* On Linux, the pidfd_getpid function has been added.  It allows retrieving
  the process ID associated with the process file descriptor created by
  pid_spawn, fork_np, or pidfd_open.

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

* A new tunable, glibc.mem.decorate_maps, can be used to add additional
  information on underlying memory allocated by the glibc (for instance,
  on thread stack created by pthread_create or memory allocated by
  malloc).

* The <stdbit.h> header has been added from ISO C2X, with
  stdc_leading_zeros, stdc_leading_ones, stdc_trailing_zeros,
  stdc_trailing_ones, stdc_first_leading_zero, stdc_first_leading_one,
  stdc_first_trailing_zero, stdc_first_trailing_one, stdc_count_zeros,
  stdc_count_ones, stdc_has_single_bit, stdc_bit_width, stdc_bit_floor
  and stdc_bit_ceil function families, each having functions for
  unsigned char, unsigned short, unsigned int, unsigned long int and
  unsigned long long int, and a type-generic macro.

* On AArch64 new symbols were added to libmvec and now math.h has
  annotations to allow GCC 9 or newer to auto-vectorize calls to the
  following scalar math functions when -ffast-math is specified:
  acos, acosf, asin, asinf, atan, atanf, atan2, atan2f, cos, cosf,
  exp, expf, exp10, exp10f, exp2, exp2f, expm1, expm1f, log, logf,
  log10, log10f, log1p, log1pf, log2, log2f, sin, sinf, tan, tanf.

Deprecated and removed features, and other changes affecting compatibility:

* The ldconfig program now skips file names containing ';' or ending in
  ".dpkg.tmp" or ".dpkg.new", to avoid examining temporary files created
  by the RPM and dpkg package managers.

* libcrypt has been removed from the GNU C Library.  The configure
  options "--enable-crypt" and "--enable-nss-crypt" are no longer
  available.  <crypt.h>, libcrypt.a, and libcrypt.so.1 will not be
  installed.  For now <unistd.h> continues to declare the crypt
  function by default, to avoid introducing vulnerabilities into
  existing applications due to a missing prototype.  This declaration
  is deprecated and may be removed in a future glibc release.

  The replacement for libcrypt is libxcrypt, maintained separately from
  GNU libc, but available under compatible licensing terms, and providing
  binary backward compatibility with the former libcrypt.  It is currently
  distributed from <https://github.com/besser82/libxcrypt/>.

  As a consequence of this removal, GNU libc no longer makes any use of
  the NSS cryptography library (Network Security Services; not to be
  confused with Name Service Switch).  Distributors of binary packages
  of GNU libc are advised to check whether their build processes can be
  simplified.

* The dynamic linker calls the malloc and free functions in more cases
  during TLS access if a shared object with dynamic TLS is loaded and
  unloaded.  This can result in an infinite recursion if a malloc
  replacement library or its dependencies use dynamic TLS instead of
  initial-exec TLS.

* The ia64*-*-linux-gnu configurations are no longer supported.

Changes to build and runtime requirements:

* Building on LoongArch requires at a minimum binutils 2.41 for vector
  instructions.

Security related changes:

The following CVEs were fixed in this release, details of which can be
found in the advisories directory of the release tarball:

  GLIBC-SA-2023-0002:
    getaddrinfo: Stack read overflow in no-aaaa mode (CVE-2023-4527)

  GLIBC-SA-2023-0003:
    getaddrinfo: Potential use-after-free (CVE-2023-4806)

  GLIBC-SA-2023-0004:
    tunables: local privilege escalation through buffer overflow
    (CVE-2023-4911)

  GLIBC-SA-2024-0001:
    syslog: Heap buffer overflow in __vsyslog_internal (CVE-2023-6246)

  GLIBC-SA-2024-0002:
    syslog: Heap buffer overflow in __vsyslog_internal (CVE-2023-6779)

  GLIBC-SA-2024-0003:
    syslog: Integer overflow in __vsyslog_internal (CVE-2023-6780)

  GLIBC-SA-2024-0004:
    ISO-2022-CN-EXT: fix out-of-bound writes when writing escape
    sequence (CVE-2024-2961)

  GLIBC-SA-2024-0005:
    nscd: Stack-based buffer overflow in netgroup cache (CVE-2024-33599)

  GLIBC-SA-2024-0006:
    nscd: Null pointer crashes after notfound response
    (CVE-2024-33600)

  GLIBC-SA-2024-0007:
    nscd: netgroup cache may terminate daemon on memory allocation
    failure (CVE-2024-33601)

  GLIBC-SA-2024-0008:
    nscd: netgroup cache assumes NSS callback uses in-buffer strings
    (CVE-2024-33602)

The following bugs are resolved with this release:

  [14522] localedata: fy_DE: LC_IDENTIFICATION data looks weird
  [19305] libc: qsort() should return early if (nmemb <= 1)
  [19479] localedata: gbm_IN: new Garhwali Locale
  [19924] dynamic-link: TLS performance degradation after dlopen
  [19956] localedata: ssy_ER: rename from aa_ER@saaho
  [21719] libc: stdlib/msort : optimizing merge sort
  [22526] localedata: th_TH  LC_COLLATE does not use copy "iso14651_t1"
  [23012] localedata: el_GR: Greece now uses the 24h format for time
  [23172] localedata: miq_NI: Provide actually abbreviated month names
  [24006] localedata: Cyclic dependencies via copy in locales
  [24013] localedata: am_pm definitions for es_ES
  [24386] localedata: crh_RU: new locale
  [24877] localedata: [Redundant Data] Remove redundant data between
    en_NZ and en_AU
  [25868] localedata: Incorrect trailing spaces in weekday names for
    nn_NO
  [26752] localedata: Please add the new locale zgh_MA
  [27069] dynamic-link: Need a way to tell if a tunable is set by user
  [27163] localedata: Error on test glk_IR with localedef
  [27312] localedata: su_ID: new Sundanese locale
  [27547] manual: "Summary of malloc-Related Functions" shows wrong
    argument order for  `aligned_alloc` and `memalign`
  [27574] libc: glibc should probably not define __WORDSIZE=64 for
    __sparcv9
  [27601] localedata: License information update in
    localedata/locales/ast_ES
  [28558] localedata: it_IT LC_MONETARY outdated p_cs_precedes and
    n_cs_precedes
  [28787] localedata: Add information for Occitan
  [29039] dynamic-link: Corrupt DTV after reuse of a TLS module ID
    following dlclose with unused TLS
  [29486] localedata: New Zealand locales (en_NZ & mi_NZ) first day of
    week should be Monday
  [29504] localedata: Incorrect/misleading Time Format For ms_MY (AM/PM)
  [29506] localedata: UTF-8 HANGUL SYLLABLE bugs
  [30349] libc: Support returning a pidfd from posix_spawn()
  [30412] localedata: d_t_fmt in id_ID uses %r placeholder but am_pm and
    t_fmt_ampm are undefined
  [30605] localedata: New locale for Komi language
  [30649] localedata: [PATCH] Add transliteration of common emojis to
    smileys
  [30694] locale: The iconv program no longer tells the user which given
    encoding name was wrong
  [30709] nscd: nscd fails to build with cleanup handler if built with
    -fexceptions
  [30737] libc: fdopendir() is not robust - returns bogus DIR* instead
    of flagging an error
  [30740] build: [m68k] undefined reference to
    `_wordcopy_fwd_dest_aligned'
  [30745] libc: Slight bug in cache info codes for x86
  [30750] network: Unaligned accesses in resolver
  [30773] math: [m68k] busybox awk is broken (lshift.S related)
  [30789] libc: [2.38 Regression] sem_open will fail on multithreaded
    scenarios when semaphore file doesn't exist (O_CREAT)
  [30800] nscd: Improper assert in prune_cache triggers if clock jumps
    backwards
  [30804] libc: F_GETLK, F_SETLK, and F_SETLKW value change for
    powerpc64 with -D_FILE_OFFSET_BITS=64
  [30842] network: Stack read overflow in getaddrinfo in no-aaaa mode
    (CVE-2023-4527)
  [30843] network: potential use-after-free in getcanonname
    (CVE-2023-4806)
  [30854] localedata: Update locale data to Unicode 15.1.0
  [30884] network: Memory leak in getaddrinfo after fix for bug 30843
    (CVE-2023-5156)
  [30932] libc: Fortify Source has false-positives when too many files
    are open
  [30945] malloc: Core affinity setting incurs lock contentions between
    threads
  [30960] math: signed integer overflow in
    glibc/sysdeps/s390/fpu/feenablxcpt.c
  [30964] locale: Number grouping check mishandles multibyte thousands
    separator
  [30981] dynamic-link: dlclose does not properly implement force-first
    handling
  [30988] math: fesetexcept raises floating-point exception traps on
    ppc, ppc64, ppc64le
  [30989] math: fesetexcept raises floating-point exception traps on
    i386
  [30990] libc: fesetexceptflag raises floating-point exception traps on
    i386, x86_64
  [30998] math: fesetexceptflag clears too many floating-point exception
    flags on alpha
  [31019] manual: The documentation of feenableexcept is incomplete
  [31022] math: feupdateenv (FE_DFL_ENV) crashes on riscv
  [31035] libc: Library search path terminates on relative non-directory
    name
  [31042] libc: [s390x] .init and .fini padding
  [31068] libc: sysdeps: sparc: invalid data access in memset due to
    regression
  [31078] manual: Code example in "Noncanonical Mode Example" has unused
    'char *name;'
  [31086] localedata: Errors in Tibetan, Dzongkha data
  [31113] string: Wrong unwind information for rawmemchr on aarch64
  [31151] libc: [RISC-V] missing support for profile/audit PLT setup
  [31163] nss: getaddrinfo returns EAI_NONAME in oom situation
  [31183] stdio: Wide stream buffer size reduced MB_LEN_MAX bytes after
    bug 17522 fix
  [31184] dynamic-link: FAIL: elf/tst-tlsgap
  [31185] dynamic-link: Incorrect thread point access in
    _dl_tlsdesc_undefweak and _dl_tlsdesc_dynamic
  [31187] dynamic-link: Some CET tests fail with GCC 14
  [31204] localedata: Fix decimal point and thousands separator for
    uz_UZ
  [31205] localedata: Inconsistent (mon_)grouping formats
  [31218] dynamic-link: PLT rewrite overflows large displacement on x32
  [31221] localedata: Add localedata for ISO code "tok" (Toki Pona)
  [31230] dynamic-link: PLT rewrite failed without SELinux
  [31239] localedata: anp_IN locale: abbreviated month names are the
    same as the full month names
  [31244] nptl: pthread_cancel hangs on sparc32
  [31257] localedata: Sync with  CLDR: “Turkey” -> “Türkiye”
  [31266] string: sparc: string/tst-memmove-overflow fails on 32-bit
    sparcv9
  [31276] libc: Wrong condition for heap allocation in qsort_r

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.

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:
