valgrind-3.27.0

[Bruce Dubbs]

New minor version.

[Bruce Dubbs]

Release 3.27.0 (20 Apr 2026)

CORE CHANGES

• There are two new client requests

• VALGRIND_REPLACES_MALLOC Returns 1 if the tool replaces malloc (e.g., memcheck). Returns 0 if the tool does not replace malloc (e.g., cachegrind and callgrind) or if the executable is not running under VALGRIND.

• VALGRIND_GET_TOOLNAME Get the running tool name as a string. Takes two arguments, an input buffer pointer and the length of that buffer. Returns the required length (including terminating nul) for the tool name. Returns 0 and the contents supplied buffer are not modified if not running under Valgrind.

See also the full description in the valgrind.h header file or the in The Client Request mechanism section of the Valgrind User Manual.

• linux lightweight guard pages (madvise MADV_GUARD_INSTALL) supported

glibc 2.42+ (with linux 6.13+) uses MADV_GUARD_INSTALL to setup stack guard pages. These lightweight guard pages are now supported under valgrind. By default, Valgrind can handle to up to 500 madvise guard pages. With thread heavy workloads the default value might not be sufficient. Use --max-guard-pages=N to provide a different limit. If --max-guard-pages is not set explicitly, then it will default to the --max-threads setting.

• --num-callers now has a minimum value of 2.

PLATFORM CHANGES

• x86: Support for SSE4.1 instructions has been ported from AMD64 to (32bit) x86. This is ongoing work. Currently the following SSE4.1 instructions are supported BLENDPD BLENDPS BLENDVPD BLENDVPS MOVNTDQA MPSADBW PBLENDVB PBLENDW PCMPEQQ PINSRD PMAXSB PMAXSD PMAXUD PMAXUW PMINSB PMINSD PMINUD PMINUW PMULLD PTEST. Bug #518222 tracks further progress.

• s390x: Machine models older than z196 are no longer supported.

• s390x: Support new z/Architecture features from the 15th edition. In particular this enables running binaries compiled with `-march=arch15' or `-march=z17' and exploiting the new MSA extensions 10-13.

• Support for the following macOS versions has been added

    10.13 High Sierra (bug fixes)
    10.14 Mojave
    10.15 Catalina
    11.0  Big Sur (Intel only)
    12.0  Monterey (Intel only)
    13.0  Ventura (Intel only, preliminary)
  

• The Linux Test Project (LTP) v20260130 was integrated. New linux syscall wrappers for file_getattr, file_setattr, lsm_get_self_attr, lsm_set_self_attr, lsm_list_modules were added.

TOOL CHANGES

• Helgrind:

• New debug option --show-events=0|1|2. Controls tracing of internal Helgrind synchronization, threading and memory events. At level 1, Helgrind prints a trace of its synchronization, threading and memory events. At level 2, additional memory events are also traced. The default value of 0 disables tracing.

• New option --track-destroy=no|yes|all. Checks for missing pthread_mutex_destroy and pthread_rwlock_destroy calls. With yes, Helgrind warns when pthread_mutex_init or pthread_rwlock_init is called on the address of a live (undestroyed) lock. With all, Helgrind also reports undestroyed locks at process exit. --track-destroy does not track locks that use static initializers.

FIXED BUGS

126256  (fnop) vex x86->IR: unhandled instruction bytes: 0xD9 0xD0 0x31 0xC0
228343  none/tests/darwin/bug228343 fails on OS X
233298  MEMPOOL_FREE not reflected in heap summary
253436  vex amd64->IR: unhandled instruction bytes: 0xF2 0xA6 (repne cmps)
258140  Valgrind on OS X always reports some memory "still reachable"
390754  unhandled amd64-darwin syscall: unix:216 (open_dprotected_np)
406674  False positive when reading bitfield value on code compiled with
        clang 7.0
413369  unhandled amd64-darwin syscall: unix:151 (getpgid)
413410  unhandled amd64-darwin syscall: mach:50 (on macOS 10.15)
487055  memcheck/tests/x86-linux/scalar fails running in Docker
503238  s390x: Support miscellaneous-instruction-extensions facility 4
503239  s390x: Support vector-enhancements facility 3
503240  s390x: Support MSA extensions 10, 11, and 12
509562  s390x: Define minimum required machine model
510416  Missing syswraps for file_getattr and file_setattr
510563  Add missing syswraps for lsm_get_self_attr and lsm_set_self_attr
510864  Add SSE4.1 PMAXSD and PMINSD instructions support for 32-bit x86
511329  Darwin and FreeBSD: Move setting of carry flag out of
        ML_(do_syscall_for_client_WRK)
511461  Darwin 17 (MacOS X 10.13) memcheck issues
511713  Refactor syscall argument handling
511717  gdbserver (valgrind_read_memory) the 'impossible' happened:
        Killed by fatal signal (SIGSEGV)
511972  valgrind-3.26.0 tests fail to build on upcomig gcc-16:
        unrecognized command-line option
        '-Wno-alloc-size-larger-than=18446744073709551615'
512030  s390x: bfp-convert testcase fails
512037  malloc trace does not print free size or alignment
512291  Valgrind on Solaris should drop support for long gone /dev/crypto
        framework
512571  regtest problems with darwin dsymutil
512873  Add SSE4.1 min/max instructions for x86 32 bit
513257  Add missing syswraps for lsm_list_modules
513522  m_libcassert.c: 'ordered comparison of pointer with integer zero'
        compiler warning
513475  Add SSE4.1 PMULLD instruction for x86 32 bit
513598  Helgrind should detect locks without pthread_{rwlock,mutex}_destroy
        being called - Assertion 'lk->kind == LK_rdwr' failed.
514094  readlink("/proc/self/exe") overwrites buffer beyond its return value
514206  Assertion '!sr_isError(sr)' failed - mmap fd points to an open
        descriptor to a PCI device
514297  Track madvise MADV_GUARD_INSTALL in address space manager
514343  Add a valgrind.h macro VALGRIND_REPLACES_MALLOC
514596  Add SSE4.1 BLENDPD instruction for x86 32 bit
514613  Unclosed leak_summary/still_reachable tag in xml output
514659  ltp 20250930 vs linux 6.18.3 doesn't build
514762  Many "Bad file descriptor" messages when using --track-fds=yes and
        -d on systems without /proc
515183  Error occurred while executing the command
        `valgrind --num-callers=1 ./hello_world`
515265  Add SSE4.1 BLENDPS and PBLENDW instructions for x86 32 bit
516223  Add SSE4.1 PBLENDVB, BLENDVPS and BLENDVPD
        instructions for x86 32 bit
515612  Sanity check VG_(realpath) and VG_(readlink) return values
515731  Distinguish between realloc functions in realloc size 0 error messages
515810  Update the LTP version in valgrind testsuite to 20260130
515992  Add FreeBSD /proc virtualisation for cmdline and file
516090  Regression : Linux FreeBSD and Darwin: refactor *at syscall dirfd checks
516225  Add MOVNTDQA SSE4.1 support for x86
516289  illumos lsframe2 regtest fails
516748  Incorrect use of SET_STATUS_Failure for syscall wrappers that return
        error codes rather than -1 on error
517455  Add PCMPEQQ SSE4.1 support for x86
517697  Implement CLRSSONSTACK and SETUJMPBUF handling on Solaris.
517748  Add ability to redirect global functions to Darwin
517840  Add PTEST SSE4.1 support for x86
518216  Add SSE4.1 MPSADBW instruction support for x86 32 bit
518076  FreeBSD: add syscall wrapper for renameat2
518078  Configure should accept names for GDB other than "gdb"
518159  pth_once issues on Darwin
518482  FreeBSD: assert in parse_procselfmaps when built with GNU binutils
518609  Setting double verbose interferes with symbol loading (FreeBSD 16)
518778  Valgrind LTP testsuite fails to compile on Fedora 44+
518951  LTP testcase fsconfig02 fails under Valgrind

[Bruce Dubbs]

Fix at commits:

d0b356c3dd Update to git-2.54.0.
6542509816 Update to valgrind-3.27.0.
d9e2e7a4cf Update to LVM2.2.03.40.