Update memcheck description of C++ new and delete

[valgrind.git] / NEWS

Release 3.23.0 (26 Apr 2024)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This release supports X86/Linux, AMD64/Linux, ARM32/Linux, ARM64/Linux,
PPC32/Linux, PPC64BE/Linux, PPC64LE/Linux, S390X/Linux, MIPS32/Linux,
MIPS64/Linux, ARM/Android, ARM64/Android, MIPS32/Android, X86/Android,
X86/Solaris, AMD64/Solaris, AMD64/MacOSX 10.12, X86/FreeBSD, AMD64/FreeBSD
and ARM64/FreeBSD  There is also preliminary support for X86/macOS 10.13,
AMD64/macOS 10.13 and nanoMIPS/Linux.

* ==================== CORE CHANGES ===================

* --track-fds=yes will now also warn about double closing of file
  descriptors. Printing the context where the file descriptor was
  originally opened and where it was previously closed.

* --track-fds=yes also produces "real" errors now which can be
  suppressed and work with --error-exitcode. When combined with
  --xml the xml-output now also includes FdBadClose and FdNotClosed
  error kinds (see docs/internals/xml-output-protocol5.txt).

* The option --show-error-list=no|yes now accepts a new value all.
  This indicates to also print the suppressed errors.
  This is useful to analyse which errors are suppressed by which
  suppression entries.
  The valgrind monitor command 'v.info all_errors' similarly now
  accepts a new optional argument 'also_suppressed' to show
  all errors including the suppressed errors.

* ================== PLATFORM CHANGES =================

* Added ARM64 support for FreeBSD.

* ARM64 now supports dotprod instructions (sdot/udot).

* AMD64 better supports code build with -march=x86-64-v3.
  fused-multiple-add instructions (fma) are now emulated more
  accurately. And memcheck now handles __builtin_strcmp using 128/256
  bit vectors with sse4.1, avx/avx2.

* S390X added support for NNPA (neural network processing assist)
  facility vector instructions VCNF, VCLFNH, VCFN, VCLFNL, VCRNF and
  NNPA (z16/arch14).

* X86 recognizes new binutils-2.42 nop patterns.

* ==================== TOOL CHANGES ===================

* The none tool now also supports xml output.

* ==================== FIXED BUGS ====================

The following bugs have been fixed or resolved.  Note that "n-i-bz"
stands for "not in bugzilla" -- that is, a bug that was reported to us
but never got a bugzilla entry.  We encourage you to file bugs in
bugzilla (https://bugs.kde.org/enter_bug.cgi?product=valgrind) rather
than mailing the developers (or mailing lists) directly -- bugs that
are not entered into bugzilla tend to get forgotten about or ignored.


283429  ARM leak checking needs CLEAR_CALLER_SAVED_REGS
281059  Cannot connect to Oracle using valgrind
328563  make track-fds support xml output
362680  --error-exitcode not honored when file descriptor leaks are found
369723  __builtin_longjmp not supported in clang/llvm on Android arm64 target
390269  unhandled amd64-darwin syscall: unix:464 (openat_nocancel)
401284  False positive "Source and destination overlap in strncat"
428364  Signals inside io_uring_enter not handled
437790  valgrind reports "Conditional jump or move depends on uninitialised
        value" in memchr of macOS 10.12-10.15
460616  disInstr(arm64): unhandled instruction 0x4E819402 (dotprod/ASIMDDP)
463458  memcheck/tests/vcpu_fnfns fails when glibc is built for x86-64-v3
463463  none/tests/amd64/fma fails when executed on a x86-64-v3 system
466762  Add redirs for C23 free_sized() and free_aligned_sized()
466884  Missing writev uninit padding suppression for _XSend
471036  disInstr_AMD64: disInstr miscalculated next %rip on RORX imm8, m32/64, r32/6
471222  support tracking of file descriptors being double closed
474160  If errors-for-leak-kinds is specified, exit-on-first-error should only exit
        on one of the listed errors.
475498  Add reallocarray wrapper
476025  Vbit expected test results for Iop_CmpGT64Ux2 are wrong
476320  Build failure with GCC
476331  clean up generated/distributed filter scripts
476535  Difference in allocation size for massif/tests/overloaded-new between
        clang++/libc++ and g++/libstdc++
476548  valgrind 3.22.0 fails on assertion when loading debuginfo file
        produced by mold
476708  valgrind-monitor.py regular expressions should use raw strings
476780  Extend strlcat and strlcpy wrappers to GNU libc
476787  Build of Valgrind 3.21.0 fails when SOLARIS_PT_SUNDWTRACE_THRP is
        defined
476887  WARNING: unhandled amd64-freebsd syscall: 578
477198  Add fchmodat2 syscall on linux
477628  Add mremap support for Solaris
477630  Include ucontext.h rather than sys/ucontext.h in Solaris sources
477719  vgdb incorrectly replies to qRcmd packet
478211  Redundant code for vgdb.c and Valgrind core tools
478624  Valgrind incompatibility with binutils-2.42 on x86 with new nop patterns
        (unhandled instruction bytes: 0x2E 0x8D 0xB4 0x26
478837  valgrind fails to read debug info for rust binaries
479041  Executables without RW sections do not trigger debuginfo reading
480052  WARNING: unhandled amd64-freebsd syscall: 580
480126  Build failure on Raspberry Pi 5 / OS 6.1.0-rpi7-rpi-v8
480405  valgrind 3.22.0 "m_debuginfo/image.c:586 (set_CEnt):
        Assertion '!sr_isError(sr)' failed."
480488  Add support for FreeBSD 13.3
480706  Unhandled syscall 325 (mlock2)
481127  amd64: Implement VFMADD213 for Iop_MAddF32
481131  [PATCH] x86 regtest: fix clobber lists in generated asm statements
481676  Build failure on Raspberry Pi 5 Ubuntu 23.10 with clang
481874  Add arm64 support for FreeBSD
483786  Incorrect parameter indexing in FreeBSD clock_nanosleep syscall wrapper
484002  Add suppression for invalid read in glibc's __wcpncpy_avx2() via wcsxfrm()
484426  aarch64: 0.5 gets rounded to 0
484480  False positives when using sem_trywait
484935  [patch] Valgrind reports false "Conditional jump or move depends on
        uninitialised value" errors for aarch64 signal handlers
485148  vfmadd213ss instruction is instrumented incorrectly (the remaining
        part of the register is cleared instead of kept unmodified)
485487  glibc built with -march=x86-64-v3 does not work due to ld.so strcmp
485778  Crash with --track-fds=all and --gen-suppressions=all
n-i-bz  Add redirect for memccpy

To see details of a given bug, visit
  https://bugs.kde.org/show_bug.cgi?id=XXXXXX
where XXXXXX is the bug number as listed above.

(3.23.0.RC1: 19 Apr 2024)
(3.23.0.RC2: 24 Apr 2024)

Release 3.22.0 (31 Oct 2023)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This release supports X86/Linux, AMD64/Linux, ARM32/Linux, ARM64/Linux,
PPC32/Linux, PPC64BE/Linux, PPC64LE/Linux, S390X/Linux, MIPS32/Linux,
MIPS64/Linux, ARM/Android, ARM64/Android, MIPS32/Android, X86/Android,
X86/Solaris, AMD64/Solaris, AMD64/MacOSX 10.12, X86/FreeBSD and
AMD64/FreeBSD.  There is also preliminary support for X86/macOS 10.13,
AMD64/macOS 10.13 and nanoMIPS/Linux.

* ==================== CORE CHANGES ===================

* A new configure option --with-gdbscripts-dir lets you install
  the gdb valgrind python monitor scripts in a specific location.
  For example a distro could use it to install the scripts in a
  safe load location --with-gdbscripts-dir=%{_datadir}/gdb/auto-load
  It is also possible to configure --without-gdb-scripts-dir so no
  .debug_gdb_scripts section is added to the vgpreload library and
  no valgrind-monitor python scripts are installed at all.

* ================== PLATFORM CHANGES =================

* Support has been added for FreeBSD 14 and FreeBSD 15.
* Add support for the folllowing FreeBSD system calls:
  close_range, kqueuex, membarrier, timerfd_create,
  timerfd_settime and timerfd_gettime (all added in FreeBSD 15).

* ==================== TOOL CHANGES ===================

* Memcheck now tests and warns about the values used for
  alignment and size. These apply to various functions: memalign,
  posix_memalign and aligned_alloc in C and various overloads
  of operators new and delete in C++. The kinds of error that can
  be detected are
  - invalid alignment, for instance the alignment is usually required
    to be a power of 2
  - mismatched alignment between aligned allocation and aligned
    deallocation
  - mismatched size when sized delete is used
  - bad size for functions that have implementation defined behaviour
    when the requested size is zero

* Cachegrind:
  - You can now profile part of a program's execution using the new
    `CACHEGRIND_START_INSTRUMENTATION` and `CACHEGRIND_STOP_INSTRUMENTATION`
    client requests, along with the new `--instr-at-start` option. The
    behaviour is the same as Callgrind's equivalent functionality.

* ==================== FIXED BUGS ====================

The following bugs have been fixed or resolved.  Note that "n-i-bz"
stands for "not in bugzilla" -- that is, a bug that was reported to us
but never got a bugzilla entry.  We encourage you to file bugs in
bugzilla (https://bugs.kde.org/enter_bug.cgi?product=valgrind) rather
than mailing the developers (or mailing lists) directly -- bugs that
are not entered into bugzilla tend to get forgotten about or ignored.

390871  ELF debug info reader confused with multiple .rodata* sections
417993  vbit-test fail on s390x with Iop_Add32: spurious dependency on uninit
426751  Valgrind reports "still reachable" memory using musl
        (alpine running inside docker)
432801  Valgrind 3.16.1 reports a jump based on uninitialized memory somehow
        related to clang and signals
433857  Add validation to C++17 aligned new/delete alignment size
433859  Add mismatched detection to C++ 17 aligned new/delete
460192  Add epoll_pwait2
461074  DWARF2 CFI reader: unhandled DW_OP_ 0x11 (consts) DW_OP_ 0x92 (bregx)
465782  s390x: Valgrind doesn't compile with Clang on s390x
466105  aligned_alloc problems, part 2
467441  Add mismatched detection to C++ 14 sized delete
469049  link failure on ppc64 (big endian) valgrind 3.20
469146  massif --ignore-fn does not ignore inlined functions
469768  Make it possible to install gdb scripts in a different location
470121  Can't run callgrind_control with valgrind 3.21.0 because of perl errors
470132  s390x: Assertion failure on VGM instruction
470520  Multiple realloc zero errors crash in MC_(eq_Error)
470713  Failure on the Yosys project: valgrind: m_libcfile.c:1802
        (Bool vgPlain_realpath(const HChar *, HChar *)):
        Assertion 'resolved' failed
470830  Don't print actions vgdb me ... continue for vgdb --multi mode
470978  s390x: Valgrind cannot start qemu-kvm when "sysctl vm.allocate_pgste=0"
471311  gdb --multi mode stdout redirecting to stderr
471807  Add support for lazy reading and downloading of DWARF debuginfo
472219  Syscall param ppoll(ufds.events) points to uninitialised byte(s)
472875  none/tests/s390x/dfp-1 failure 
472963  Broken regular expression in configure.ac
473604  Fix bug472219.c compile failure with Clang 16
473677  make check compile failure with Clang 16 based on GCC 13.x
473745  must-be-redirected function - strlen
473870  FreeBSD 14 applications fail early at startup
473944  Handle mold linker split RW PT_LOAD segments correctly
474332  aligned_alloc under Valgrind returns nullptr when alignment is not a multiple of sizeof(void *)
475650  DRD does not work with C11 threads
475652  Missing suppression for __wcsncpy_avx2 (strncpy-avx2.S:308)?
476108  vg_replace_malloc DELETE checks size
n-i-bz  Allow arguments with spaces in .valgrindrc files
n-i-bz  FreeBSD fixed reading of Valgrind tools own debuginfo

To see details of a given bug, visit
  https://bugs.kde.org/show_bug.cgi?id=XXXXXX
where XXXXXX is the bug number as listed above.

(3.22.0.RC1: 17 Oct 2023)
(3.22.0.RC2: 26 Oct 2023)

Release 3.21.0 (28 Apr 2023)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This release supports X86/Linux, AMD64/Linux, ARM32/Linux, ARM64/Linux,
PPC32/Linux, PPC64BE/Linux, PPC64LE/Linux, S390X/Linux, MIPS32/Linux,
MIPS64/Linux, ARM/Android, ARM64/Android, MIPS32/Android, X86/Android,
X86/Solaris, AMD64/Solaris, AMD64/MacOSX 10.12, X86/FreeBSD and
AMD64/FreeBSD.  There is also preliminary support for X86/macOS 10.13,
AMD64/macOS 10.13 and nanoMIPS/Linux.

* ==================== CORE CHANGES ===================

* When GDB is used to debug a program running under valgrind using
  the valgrind gdbserver, GDB will automatically load some
  python code provided in valgrind defining GDB front end commands
  corresponding to the valgrind monitor commands.
  These GDB front end commands accept the same format as
  the monitor commands directly sent to the Valgrind gdbserver.
  These GDB front end commands provide a better integration
  in the GDB command line interface, so as to use for example
  GDB auto-completion, command specific help, searching for
  a command or command help matching a regexp, ...
  For relevant monitor commands, GDB will evaluate arguments
  to make the use of monitor commands easier.
  For example, instead of having to print the address of a variable
  to pass it to a subsequent monitor command, the GDB front end
  command will evaluate the address argument. It is for example
  possible to do:
    (gdb) memcheck who_points_at &some_struct sizeof(some_struct)
  instead of:
    (gdb) p &some_struct
    $2 = (some_struct_type *) 0x1130a0 <some_struct>
    (gdb) p sizeof(some_struct)
    $3 = 40
    (gdb) monitor who_point_at 0x1130a0 40

* The vgdb utility now supports extended-remote protocol when
  invoked with --multi. In this mode the GDB run command is
  supported. Which means you don't need to run gdb and valgrind
  from different terminals. So for example to start your program
  in gdb and run it under valgrind you can do:
  $ gdb prog
  (gdb) set remote exec-file prog
  (gdb) set sysroot /
  (gdb) target extended-remote | vgdb --multi
  (gdb) start

* The behaviour of realloc with a size of zero can now
  be changed for tools that intercept malloc. Those
  tools are memcheck, helgrind, drd, massif and dhat.
  Realloc implementations generally do one of two things
     - free the memory like free() and return NULL
       (GNU libc and ptmalloc).
     - either free the memory and then allocate a
       minimum sized block or just return the
       original pointer. Return NULL if the
       allocation of the minimum sized block fails
       (jemalloc, musl, snmalloc, Solaris, macOS).
  When Valgrind is configured and built it will
  try to match the OS and libc behaviour. However
  if you are using a non-default library to replace
  malloc and family (e.g., musl on a glibc Linux or
  tcmalloc on FreeBSD) then you can use a command line
  option to change the behaviour of Valgrind:
    --realloc-zero-bytes-frees=yes|no [yes on Linux glibc, no otherwise]

* ================== PLATFORM CHANGES =================

* Make the address space limit on FreeBSD amd64 128Gbytes
  (the same as Linux and Solaris, it was 32Gbytes)

* ==================== TOOL CHANGES ===================

* Memcheck:
  - When doing a delta leak_search, it is now possible to only
    output the new loss records compared to the previous leak search.
    This is available in the memcheck monitor command 'leak_search'
    by specifying the "new" keyword or in your program by using
    the client request VALGRIND_DO_NEW_LEAK_CHECK.
    Whenever a "delta" leak search is done (i.e. when specifying
    "new" or "increased" or "changed" in the monitor command),
    the new loss records have a "new" marker.
  - Valgrind now contains python code that defines GDB memcheck
    front end monitor commands. See CORE CHANGES.
  - Performs checks for the use of realloc with a size of zero.
    This is non-portable and a source of errors. If memcheck
    detects such a usage it will generate an error
      realloc() with size 0
    followed by the usual callstacks.
    A switch has been added to allow this to be turned off:
      --show-realloc-size-zero=yes|no [yes]

* Helgrind:
  - The option ---history-backtrace-size=<number> allows to configure
    the number of entries to record in the stack traces of "old"
    accesses. Previously, this number was hardcoded to 8.
  - Valgrind now contains python code that defines GDB helgrind
    front end monitor commands. See CORE CHANGES.

* Cachegrind:
  - `--cache-sim=no` is now the default. The cache simulation is old and
    unlikely to match any real modern machine. This means only the `Ir`
    event are gathered by default, but that is by far the most useful
    event.
  - `cg_annotate`, `cg_diff`, and `cg_merge` have been rewritten in
    Python. As a result, they all have more flexible command line
    argument handling, e.g. supporting `--show-percs` and
    `--no-show-percs` forms as well as the existing `--show-percs=yes`
    and `--show-percs=no`.
  - `cg_annotate` has some functional changes.
    - It's much faster, e.g. 3-4x on common cases.
    - It now supports diffing (with `--diff`, `--mod-filename`, and
      `--mod-funcname`) and merging (by passing multiple data files).
    - It now provides more information at the file and function level.
      There are now "File:function" and "Function:file" sections. These
      are very useful for programs that use inlining a lot.
    - Support for user-annotated files and the `-I`/`--include` option
      has been removed, because it was of little use and blocked other
      improvements.
    - The `--auto` option is renamed `--annotate`, though the old
      `--auto=yes`/`--auto=no` forms are still supported.
  - `cg_diff` and `cg_merge` are now deprecated, because `cg_annotate`
    now does a better job of diffing and merging.
  - The Cachegrind output file format has changed very slightly, but in
    ways nobody is likely to notice.

* Callgrind:
  - Valgrind now contains python code that defines GDB callgrind
    front end monitor commands. See CORE CHANGES.

* Massif:
  - Valgrind now contains python code that defines GDB massif
    front end monitor commands. See CORE CHANGES.

* DHAT:
  - A new kind of user request has been added which allows you to
    override the 1024 byte limit on access count histograms for blocks
    of memory. The client request is DHAT_HISTOGRAM_MEMORY.

* ==================== FIXED BUGS ====================

The following bugs have been fixed or resolved.  Note that "n-i-bz"
stands for "not in bugzilla" -- that is, a bug that was reported to us
but never got a bugzilla entry.  We encourage you to file bugs in
bugzilla (https://bugs.kde.org/enter_bug.cgi?product=valgrind) rather
than mailing the developers (or mailing lists) directly -- bugs that
are not entered into bugzilla tend to get forgotten about or ignored.

170510  Don't warn about ioctl of size 0 without direction hint
241072  List tools in --help output
327548  false positive while destroying mutex
382034  Testcases build fixes for musl
351857  confusing error message about valid command line option
374596  inconsistent RDTSCP support on x86_64
392331  Spurious lock not held error from inside pthread_cond_timedwait
397083  Likely false positive "uninitialised value(s)" for __wmemchr_avx2 and __wmemcmp_avx2_movbe
400793  pthread_rwlock_timedwrlock false positive
419054  Unhandled syscall getcpu on arm32
433873  openat2 syscall unimplemented on Linux
434057  Add stdio mode to valgrind's gdbserver
435441  valgrind fails to interpose malloc on musl 1.2.2 due to weak symbol name and no libc soname
436413  Warn about realloc of size zero
439685  compiler warning in callgrind/main.c
444110  priv/guest_ppc_toIR.c:36198:31: warning: duplicated 'if' condition.
444487  hginfo test detects an extra lock inside data symbol "_rtld_local"
444488  Use glibc.pthread.stack_cache_size tunable
444568  drd/tests/pth_barrier_thr_cr fails on Fedora 38
445743  "The impossible happened: mutex is locked simultaneously by two threads"
        while using mutexes with priority inheritance and signals
449309  Missing loopback device ioctl(s) 
459476  vgdb: allow address reuse to avoid "address already in use" errorsuse" errors
460356  s390: Sqrt32Fx4 -- cannot reduce tree
462830  WARNING: unhandled amd64-freebsd syscall: 474
463027  broken check for MPX instruction support in assembler
464103  Enhancement: add a client request to DHAT to mark memory to be histogrammed
464476  Firefox fails to start under Valgrind
464609  Valgrind memcheck should support Linux pidfd_open
464680  Show issues caused by memory policies like selinux deny_execmem
464859  Build failures with GCC-13 (drd tsan_unittest)
464969  D language demangling
465435  m_libcfile.c:66 (vgPlain_safe_fd): Assertion 'newfd >= VG_(fd_hard_limit)' failed.
466104  aligned_alloc problems, part 1
467036  Add time cost statistics for Regtest
467482  Build failure on aarch64 Alpine
467714  fdleak_* and rlimit tests fail when parent process has more than
        64 descriptors opened
467839  Gdbserver: Improve compatibility of library directory name
468401  [PATCH] Add a style file for clang-format
468556  Build failure for vgdb
468606  build: remove "Valgrind relies on GCC" check/output
469097  ppc64(be) doesn't support SCV syscall instruction
n-i-bz  FreeBSD rfork syscall fail with EINVAL or ENOSYS rather than VG_(unimplemented)

To see details of a given bug, visit
  https://bugs.kde.org/show_bug.cgi?id=XXXXXX
where XXXXXX is the bug number as listed above.

* ==================== KNOWN ISSUES ===================

* configure --enable-lto=yes is know to not work in all setups.
  See bug 469049. Workaround: Build without LTO.

(3.21.0.RC1: 14 Apr 2023)
(3.21.0.RC2: 21 Apr 2023)

Release 3.20.0 (24 Oct 2022)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This release supports X86/Linux, AMD64/Linux, ARM32/Linux, ARM64/Linux,
PPC32/Linux, PPC64BE/Linux, PPC64LE/Linux, S390X/Linux, MIPS32/Linux,
MIPS64/Linux, ARM/Android, ARM64/Android, MIPS32/Android, X86/Android,
X86/Solaris, AMD64/Solaris, AMD64/MacOSX 10.12, X86/FreeBSD and
AMD64/FreeBSD.  There is also preliminary support for X86/macOS 10.13,
AMD64/macOS 10.13 and nanoMIPS/Linux.

* ==================== CORE CHANGES ===================

* The option "--vgdb-stop-at=event1,event2,..." accepts the new value abexit.
  This indicates to invoke gdbserver when your program exits abnormally
  (i.e. with a non zero exit code).
* Fix Rust v0 name demangling.
* The Linux rseq syscall is now implemented as (silently) returning ENOSYS.
* Add FreeBSD syscall wrappers for __specialfd and __realpathat.
* Remove FreeBSD dependencies on COMPAT10, which fixes compatibility with
  HardenedBSD
* The option --enable-debuginfod=<no|yes> [default: yes] has been added on
  Linux.
* More DWARF5 support as generated by clang14.

* ==================== FIXED BUGS ====================

The following bugs have been fixed or resolved.  Note that "n-i-bz"
stands for "not in bugzilla" -- that is, a bug that was reported to us
but never got a bugzilla entry.  We encourage you to file bugs in
bugzilla (https://bugs.kde.org/enter_bug.cgi?product=valgrind) rather
than mailing the developers (or mailing lists) directly -- bugs that
are not entered into bugzilla tend to get forgotten about or ignored.

131186  writev reports error in (vector[...])
434764  iconv_open causes ld.so v2.28+ to use optimised strncmp
446754  Improve error codes from alloc functions under memcheck
452274  memcheck crashes with Assertion 'sci->status.what == SsIdle' failed
452779  Valgrind fails to build on FreeBSD 13.0 with llvm-devel (15.0.0)
453055  shared_timed_mutex drd test fails with "Lock shared failed" message
453602  Missing command line option to enable/disable debuginfod
452802  Handle lld 9+ split RW PT_LOAD segments correctly
454040  s390x: False-positive memcheck:cond in memmem on arch13 systems 
456171  [PATCH] FreeBSD: Don't record address errors when accessing the 'kern.ps_strings' sysctl struct
n-i-bz  Implement vgdb invoker on FreeBSD
458845  PowerPC: The L field for the dcbf and sync instruction should be
        3 bits in ISA 3.1.
458915  Remove register cache to fix 458915 gdbserver causes wrong syscall return
459031  Documentation on --error-exitcode incomplete
459477  XERROR messages lacks ending '\n' in vgdb
462007  Implicit int in none/tests/faultstatus.c

To see details of a given bug, visit
  https://bugs.kde.org/show_bug.cgi?id=XXXXXX
where XXXXXX is the bug number as listed above.

(3.20.0.RC1: 20 Oct 2022)


Release 3.19.0 (11 Apr 2022)
~~~~~~~~~~~~~~~~~~~~~~~~~~~~

This release supports X86/Linux, AMD64/Linux, ARM32/Linux, ARM64/Linux,
PPC32/Linux, PPC64BE/Linux, PPC64LE/Linux, S390X/Linux, MIPS32/Linux,
MIPS64/Linux, ARM/Android, ARM64/Android, MIPS32/Android, X86/Android,
X86/Solaris, AMD64/Solaris, AMD64/MacOSX 10.12, X86/FreeBSD and
AMD64/FreeBSD.  There is also preliminary support for X86/macOS 10.13,
AMD64/macOS 10.13 and nanoMIPS/Linux.

* ==================== CORE CHANGES ===================

* Fix Rust v0 name demangling.
* The Linux rseq syscall is now implemented as (silently) returning ENOSYS.
* Add FreeBSD syscall wrappers for __specialfd and __realpathat.
* Remove FreeBSD dependencies on COMPAT10, which fixes compatibility with HardenedBSD

* ================== PLATFORM CHANGES =================

* arm64:
  - ignore the "v8.x" architecture levels, only look at actual CPU features
    present. Fixes mismatch detected between RDMA and atomics features
    preventing startup on some QEMU configurations.
  - Implement LD{,A}XP and ST{,L}XP
  - Fix incorrect code emitted for doubleword CAS.

* s390:
  - Fix sys_ipc semtimedop syscall
  - Fix VFLRX and WFLRX instructions
  - Fix EXRL instruction with negative offset

* ppc64:
  - Reimplement the vbpermq instruction support to generate less Iops and
    avoid overflowing internal buffers.
  - Fix checking for scv support to avoid "Facility 'SCV' unavailable (12),
    exception" messages in dmsg.
  - Fix setting condition code for Vector Compare quad word instructions.
  - Fix fix lxsibzx, lxsihzx and lxsihzx instructions so they only load
    their respective sized data.
  - Fix the prefixed stq instruction in PC relative mode.

* ==================== TOOL CHANGES ===================

* Memcheck:
  - Speed up --track-origins=yes for large (in the range of hundreds to
    thousands of megabytes) mmap/munmaps.
* DRD/Helgrind:
  - Several fixes for new versions of libstd++ using new posix try_lock
    functions

* ==================== FIXED BUGS ====================

The following bugs have been fixed or resolved.  Note that "n-i-bz"
stands for "not in bugzilla" -- that is, a bug that was reported to us
but never got a bugzilla entry.  We encourage you to file bugs in
bugzilla (https://bugs.kde.org/enter_bug.cgi?product=valgrind) rather
than mailing the developers (or mailing lists) directly -- bugs that
are not entered into bugzilla tend to get forgotten about or ignored.

403802  leak_cpp_interior fails with some reachable blocks different than expected
435732  memcheck/tests/leak_cpp_interior fails with gcc11
444242  s390x: Valgrind crashes on EXRL with negative offset
444399  arm64: unhandled instruction 0xC87F2D89 (LD{,A}XP and ST{,L}XP).
        == 434283
444481  gdb_server test failures on s390x
444495  dhat/tests/copy fails on s390x
444552  memcheck/tests/sem fails on s390x with glibc 2.34
444571  PPC, fix the lxsibzx and lxsihzx so they only load their respective
        sized data.
444836  PPC, pstq instruction for R=1 is not storing to the correct address.
444925  fexecve syscall wrapper not properly implemented
445032  valgrind/memcheck crash with SIGSEGV when SIGVTALRM timer used and
        libthr.so associated
445211  Fix out of tree builds
445300  [PATCH] Fix building tests with Musl
445011  SIGCHLD is sent when valgrind uses debuginfod-find
445354  arm64 backend: incorrect code emitted for doubleword CAS
445415  arm64 front end: alignment checks missing for atomic instructions
445504  Using C++ condition_variable results in bogus "mutex is locked simultaneously by two threads" warning
445607  Unhandled amd64-freebsd syscall: 247
445668  Inline stack frame generation is broken for Rust binaries
445916  Demangle Rust v0 symbols with .llvm suffix
446139  DRD/Helgrind with std::shared_timed_mutex::try_lock_until and try_lock_shared_until false positives
446138  DRD/Helgrind with std::timed_mutex::try_lock_until false positives
446281  Add a DRD suppression for fwrite
446103  Memcheck: `--track-origins=yes` causes extreme slowdowns for large mmap/munmap
446139  DRD/Helgrind with std::shared_timed_mutex::try_lock_until and try_lock_shared_until false
446251  TARGET_SIGNAL_THR added to enum target_signal
446823  FreeBSD - missing syscalls when using libzm4
447991  s390x: Valgrind indicates illegal instruction on wflrx
447995  Valgrind segfault on power10 due to hwcap checking code
449483  Powerpc: vcmpgtsq., vcmpgtuq,, vcmpequq. instructions not setting the
        condition code correctly.
449672  ppc64 --track-origins=yes failures because of bad cmov addHRegUse
449838  sigsegv liburing the 'impossible' happened for io_uring_setup
450025  Powerc: ACC file not implemented as a logical overlay of the VSR
        registers.
450437  Warn for execve syscall with argv or argv[0] being NULL
450536  Powerpc: valgrind throws 'facility scv unavailable exception'
451626  Syscall param bpf(attr->raw_tracepoint.name) points to unaddressable byte(s)
451827  [ppc64le] VEX temporary storage exhausted with several vbpermq instructions
451843  valgrind fails to start on a FreeBSD system which enforces W^X

To see details of a given bug, visit
  https://bugs.kde.org/show_bug.cgi?id=XXXXXX
where XXXXXX is the bug number as listed above.

(3.19.0.RC1: 02 Apr 2022)
(3.19.0.RC2: 08 Apr 2022)