Both Mutex and CondVar signal PerThreadSem/Waiter after satisfying the wait condition,
as the result the waiting thread may return w/o waiting on the
PerThreadSem/Waiter at all. If the waiting thread then exits, it currently
destroys Waiter object. As the result Waiter::Post can be called on
already destroyed object.
PerThreadSem/Waiter must be type-stable after creation and must not be destroyed.
The futex-based implementation is the only one that is not affected by the bug
since there is effectively nothing to destroy (maybe only UBSan/ASan
could complain about calling methods on a destroyed object).
Here is the problematic sequence of events:
1: void Mutex::Block(PerThreadSynch *s) {
2: while (s->state.load(std::memory_order_acquire) == PerThreadSynch::kQueued) {
3: if (!DecrementSynchSem(this, s, s->waitp->timeout)) {
4: PerThreadSynch *Mutex::Wakeup(PerThreadSynch *w) {
5: ...
6: w->state.store(PerThreadSynch::kAvailable, std::memory_order_release);
7: IncrementSynchSem(this, w);
8: ...
9: }
Consider line 6 is executed, then line 2 observes kAvailable and
line 3 is not called. The thread executing Mutex::Block returns from
the method, acquires the mutex, releases the mutex, exits and destroys
PerThreadSem/Waiter.
Now Mutex::Wakeup resumes and executes line 7 on the destroyed object. Boom!
CondVar uses a similar pattern.
Moreover the semaphore-based Waiter implementation is not even destruction-safe
(the Waiter cannot be used to signal own destruction). So even if Mutex/CondVar
would always pair Waiter::Post with Waiter::Wait before destroying PerThreadSem/Waiter,
it would still be subject to use-after-free bug on the semaphore.
PiperOrigin-RevId: 449159939
Change-Id: I497134fa8b6ce1294a422827c5f0de0e897cea31
CondVar::WaitWithTimeout can live-lock when timeout is racing with Signal/SignalAll
and Signal/SignalAll thread is not scheduled due to priorities, affinity or other
scheduler artifacts. This could lead to stalls of up to tens of seconds in some cases.
PiperOrigin-RevId: 449159670
Change-Id: I64bbd277c1f91964cfba3306ba8a80eeadf85f64
Stop the absl::Cord destructor from running on the constinit cord in
CordTest.ConstinitConstructor. This allows inspecting the cord at any point
while the test is exiting, which is important for the semantics of the test.
PiperOrigin-RevId: 448327386
Change-Id: Icef9faa2b63f1f0ae60b3430dcf6184f5dead885
* Avoid warnings due to deprecation of volatile return types.
Also fix up optional_test.cc due to ABSL_USES_STD_OPTIONAL always being
false in its body.
Bug: chromium:1284275
PiperOrigin-RevId: 447796238
Change-Id: If050206c979c6c08af22e71ff0ea91e7f7932f0c
The old analysis viewed it as birthday attack, which asks how often
there are multiple values in the probe same probe sequence with the
same H2. In their own words, this analysis "breaks down" at around `n
= 12`.
Instead we can answer a simpler question, which is, if a probe
sequence examines `k` objects that are not what we are looking for,
what's the number of calls `==`? The expectation is simply `k/128`.
PiperOrigin-RevId: 446518063
Change-Id: Ie879bd4f6c97979822bc9d550b9e2503b1418c78
--
6d4e969ad240d248bfeb644b3b76fffae0f07882 by Christian Blichmann <cblichmann@google.com>:
cmake: Fix description of `ABSL_USE_EXTERNAL_GOOGLETEST` option
There is no `add_subproject()` in CMake.
PiperOrigin-RevId: 443087953
Change-Id: I30c2118638f99ad1389ae197e2c81d1e5f298882
GitOrigin-RevId: 6d4e969ad240d248bfeb644b3b76fffae0f07882
--
6457ad659de86ce4cae1e9f7cb03a701c6c2851e by Abseil Team <absl-team@google.com>:
Introduced ErrnoToStatusCode and ErrnoToStatus to abseil.
PiperOrigin-RevId: 442903450
Change-Id: I9c062b34a3811216f43eef56e631eada3b4e3e84
GitOrigin-RevId: 6457ad659de86ce4cae1e9f7cb03a701c6c2851e
--
3d018c03a34bf273a4b24b3584ed77f0a6d21686 by Abseil Team <absl-team@google.com>:
Fix a spelling typo (s/boundries/boundaries).
PiperOrigin-RevId: 442041877
Change-Id: I608020697d37b85316bb9a0838e4b457659c926c
--
518b8119e51db24ce7fb0fd2fe537ec43825c3e6 by Dino Radakovic <dinor@google.com>:
absl/types/internal/variant: Make include guard uppercase
https://google.github.io/styleguide/cppguide.html#The__define_Guard
PiperOrigin-RevId: 441911692
Change-Id: I9837dd07f20204d8253f20627b0917a34dc21825
--
b91696c38310a7cae8c1ea9e2d479495f5dc3f69 by Greg Falcon <gfalcon@google.com>:
Add an internal-only API to wrap __builtin_prefetch() if available.
This private API is intended for future use by the Abseil implementation. Like any internal-namespaced function, it may be changed or removed at any time.
PiperOrigin-RevId: 441894616
Change-Id: Iaa48bd4680b373f4a0d5afab0cb35e2a1908595f
--
0f01e8b0551a662e02dff60840c54320f987315f by Derek Mauro <dmauro@google.com>:
C++20: Use the standard `constinit` keyword for `ABSL_CONST_INIT` when available
PiperOrigin-RevId: 441778874
Change-Id: I70c616469752ff23b326b1c615437599f42cc6aa
GitOrigin-RevId: 3d018c03a34bf273a4b24b3584ed77f0a6d21686
--
f4c7e510922668c68be4aa79a00867c3d3ca9f95 by Derek Mauro <dmauro@google.com>:
Many improvements to LeakChecker builds
The presence of the LeakChecker is now detected when possible. GCC
users using LeakChecker in standalone mode still need to use
-DLEAK_CHECKER. This is now documented in the header.
The hacky targets used for testing leak checking have been removed in
favor of testing in AddressSanitizer mode on Kokoro.
Fixes#885Fixes#1153
PiperOrigin-RevId: 441203393
Change-Id: Ibe64ef6b104bcaf31839ff7184e558cc86abdd1c
--
5c70a23aa83b8152ab95d2cf21662fc63c80ef7d by Abseil Team <absl-team@google.com>:
Add a benchmark for stacktrace
PiperOrigin-RevId: 441196473
Change-Id: I4c9aa2e797aa2cae09abfaaee3abe5c09eb62fc4
--
50b406052273b9d5bad04a7860a96e4d5d956c02 by Abseil Team <absl-team@google.com>:
Internal change.
PiperOrigin-RevId: 441114481
Change-Id: I667af7a50d5631ca91289dd24c91ba90233e0184
--
568b4eaac120b420bce5290179d407d2b57d5bae by Dino Radakovic <dinor@google.com>:
Internal change
PiperOrigin-RevId: 440894155
Change-Id: Ia587ffc65a8321126585fb363b7c0ca8cc2a0da2
--
d53948eace4f3a10ac5a6c1496dc51b81adc412c by Abseil Team <absl-team@google.com>:
Explicitly give internal linkage to symbols which are not used outside of their
translation units.
PiperOrigin-RevId: 440424519
Change-Id: I531c5e229d443375483b7550a34f48042589a99b
GitOrigin-RevId: f4c7e510922668c68be4aa79a00867c3d3ca9f95
--
0c8848ebedc07470c7ab647a5bb8949481540ce9 by Dino Radakovic <dinor@google.com>:
Define absl::base_internal::invoke using std::invoke when C++ >= 17
PiperOrigin-RevId: 439880834
Change-Id: I3622fcf473501d54c57575118a11d54c19573446
GitOrigin-RevId: 0c8848ebedc07470c7ab647a5bb8949481540ce9
--
ef2bf829c333f378ecc12f3259e3187cdb75a3d5 by Abseil Team <absl-team@google.com>:
debugging: fix the VDSO symbol name used for unwinding on RISC-V Linux
The name listed in `man vdso` is incorrect. Instead, use the name from `linux-5.16/arch/riscv/kernel/vdso/rt_sigreturn.S`
PiperOrigin-RevId: 439654174
Change-Id: Ib39d066f416681720068e806e828a2c76a14a532
--
43dfad824afd36cfc3e5049b4fea71a2bccb066c by Benjamin Barenblat <bbaren@google.com>:
Check printf format strings in str_format_convert_test
Add ABSL_PRINTF_ATTRIBUTE to appropriate functions in
strings/internal/str_format/convert_test. Correct
TypedFormatConvertTest.Char, which was accidentally passing values of
types larger than int to StrPrint.
PiperOrigin-RevId: 439388148
Change-Id: I6cde4e8e0c6455064138192430f07f4c990be0bc
--
f84b4ab2c3b070c8af0c82742ac7a8a4bf443bca by Derek Mauro <dmauro@google.com>:
Use __builtin_memcmp in the absl::string_view implementation
starting with MSVC 16.9, where it first appeared
This enables more constexpr operations
PiperOrigin-RevId: 439317316
Change-Id: Iaf1ce76b60901d4b2d5b96be5900c56572f57b15
GitOrigin-RevId: ef2bf829c333f378ecc12f3259e3187cdb75a3d5
--
b984c7c1cbee4253192c833046bfcfa16dca8ccf by Dino Radakovic <dinor@google.com>:
Restrict visibility of absl/flags:commandlineflag_internal
PiperOrigin-RevId: 438591894
Change-Id: I12a6392b2c7f9f1263c741dfd6c43ae22e903aad
--
81315601aab70bb6ac2d17655a727d7f9ee2ff95 by Justin Lebar <jlebar@google.com>:
Update example in str_join.h to use a lambda.
PiperOrigin-RevId: 438390035
Change-Id: Icc707b972e5a369a71ad774004fdf0a17a9b33a7
--
1c3c7921224e505faca8617b073f657d3737219f by Dino Radakovic <dinor@google.com>:
Internal change
PiperOrigin-RevId: 438386036
Change-Id: I6066da1b5a1ddf5af265944a31ed298297b4f2e1
--
2d6885f78481f04e0e7ee86060aec15b677144f3 by Abseil Team <absl-team@google.com>:
Internal change
PiperOrigin-RevId: 438378389
Change-Id: If70dd9114114eb44e85afccd521e7fb7e1436b88
--
7f8282ddee7fcd032e01cbfe65c11c2d166cceb8 by Derek Mauro <dmauro@google.com>:
Internal change
PiperOrigin-RevId: 438374554
Change-Id: I993367952af1dc83bd5aa0ae19a64c024f457fdd
--
ce65ba28f6031e45db8fa5118a05410f5166fd7a by Abseil Team <absl-team@google.com>:
Spelling gardening: Heterogeneous has an "e" after the "n".
PiperOrigin-RevId: 438374411
Change-Id: If1a9098a5d04338837998883739c7b555efa62b4
GitOrigin-RevId: b984c7c1cbee4253192c833046bfcfa16dca8ccf
uclibc-ng doesn't provide getauxval which results in the following build
failure on arm or ppc with any user of abseil-cpp such as grpc:
/home/buildroot/autobuild/instance-0/output-1/host/opt/ext-toolchain/bin/../lib/gcc/arm-buildroot-linux-uclibcgnueabi/10.3.0/../../../../arm-buildroot-linux-uclibcgnueabi/bin/ld: /home/buildroot/autobuild/instance-0/output-1/host/arm-buildroot-linux-uclibcgnueabi/sysroot/usr/lib/libabsl_random_internal_randen_hwaes.so.2111.0.0: undefined reference to `getauxval'
To fix this build failure, check that __UCLIBC__ is not defined before
using getauxval (as Babel is not able to check function availability)
Fixes:
- http://autobuild.buildroot.org/results/775f3ca3dedebff29e212b29dfa896b7613b7a02
Signed-off-by: Fabrice Fontaine <fontaine.fabrice@gmail.com>
--
fb671efb2a70f452f17a884b17cf18817b977a8f by Abseil Team <absl-team@google.com>:
Remove extra semicolon in ABSL_INTERNAL_ASSERT_IS_FULL macro
To fix compilation when empty statement warning is treated as error.
PiperOrigin-RevId: 438342663
Change-Id: I3067fbeffa2691888f37554e88f229f24fb55ecc
--
a58c9396f1d88d11347aed36ef2e1b633071363c by Martijn Vels <mvels@google.com>:
Fix kMaxHeight bounds to kMaxDepth for CordrepBtreeNavigator
Added unit test (confirmed failure mode with old code) and extra assertion in the implementation.
PiperOrigin-RevId: 438327463
Change-Id: I32242c86b0c879b8a42cb9a92075e537d588e09f
--
f348e85dbfc9187ef59085fa2b999374f1670338 by Jorge Gorbe Moya <jgorbe@google.com>:
Make the flags enum in `RefcountAndFlags` a named enum to workaround an lldb
issue (https://github.com/llvm/llvm-project/issues/54602).
PiperOrigin-RevId: 438146097
Change-Id: Ibc2ee26489d99de515a779a903b6458dd0befef7
--
a960a3e9fb2a2e3418f806178e73d8566b78bc85 by Gennadiy Rozental <rogeeff@google.com>:
Introduce support for std::optional<T>/absl::optional<T> flag types.
PiperOrigin-RevId: 438129500
Change-Id: I3d925c0a7f9ce9f857277fac3b0bf664ccd3a95c
GitOrigin-RevId: fb671efb2a70f452f17a884b17cf18817b977a8f
--
291f7ef542f73e4801ab5108014bc02344ef31df by Derek Mauro <dmauro@google.com>:
Internal change
PiperOrigin-RevId: 437835981
Change-Id: I42fd92e74903894533ac9984d7f622e3ba20f468
--
2e8caf1a57c50b518e05b4bca48e4fe1bb19af82 by Andy Getzendanner <durandal@google.com>:
Internal change
PiperOrigin-RevId: 437832673
Change-Id: I61b35089418d01a54cecf161b254b68252bebff3
--
b927482ccc399f7e337b60582988b914d9946e4e by Derek Mauro <dmauro@google.com>:
Simplify endian intrinsics for modern compilers
All modern compilers have either __builtin_bswapN (gcc, clang) or
_byteswap_TYPE (MSVC). The other intrinsic definitions are no longer
necessary.
PiperOrigin-RevId: 437772295
Change-Id: Ifb3d88ba24b9097f87ceb202272b36d2f5e5117f
--
b6782a2247a16d5c14706a74ec577c19963d9f97 by Derek Mauro <dmauro@google.com>:
Internal change
PiperOrigin-RevId: 437373174
Change-Id: I0f77e1780dee90d7a3c32a08d96c4aeb624a57b4
--
a53e0c724e37b0b01515a99bd25394b8e21ffdfc by Derek Mauro <dmauro@google.com>:
Unify detection of SSE2 and SSSE3 instruction sets and
include the proper headers
Fix the intrinsic implementation of FastHexToBufferZeroPad16 in
numbers.h which only relies on SSSE3, not SSE 4.2.
https://godbolt.org/z/Pf5bn1Yv9Closes#639
PiperOrigin-RevId: 437286940
Change-Id: Ic97948399b61b91e9c0bccd09313b795b904d714
--
f173f597cb2a75ef2a989f45a496334b85e6f40d by Abseil Team <absl-team@google.com>:
Change assertion function to enable clearer error messages.
PiperOrigin-RevId: 437227057
Change-Id: If420d2f63b51feef6648762f344d5be012cd9c85
GitOrigin-RevId: 291f7ef542f73e4801ab5108014bc02344ef31df
--
8c9dd24a6fbf9ed10ae81f9fa0bc2168558a9700 by Abseil Team <absl-team@google.com>:
Improve WebAssembly detection when using Bazel.
Unfortunately, the --cpu values are not standardized, and both
--cpu=wasm and --cpu=wasm32 are used in the wild. Most notably,
Emscripten's Bazel rules use --cpu=wasm, which was missing.
While there, add support for @platforms//cpu:{wasm32,wasm64}.
This change adds a dependency on @bazel_skylib, which requires
adding the following http_archive() rule to the WORKSPACE file:
http_archive(
name = "bazel_skylib",
urls = ["https://github.com/bazelbuild/bazel-skylib/releases/download/1.2.1/bazel-skylib-1.2.1.tar.gz"],
sha256 = "f7be3474d42aae265405a592bb7da8e171919d74c16f082a5457840f06054728",
)
PiperOrigin-RevId: 436815546
Change-Id: I4e1946070c6964abb12259f25a546f2d24e0992a
--
59514589043d9b0734a01f7aa7bc354f5b495eab by Abseil Team <absl-team@google.com>:
Fix some typos that slipped through.
PiperOrigin-RevId: 436777566
Change-Id: Ibf5c54e2671c749dc87d2bd5d36dcd220ce347d4
GitOrigin-RevId: 8c9dd24a6fbf9ed10ae81f9fa0bc2168558a9700
--
bcd349230e418f5e29d5fced1b942828fa5cb2ad by Abseil Team <absl-team@google.com>:
Import of CCTZ from GitHub.
PiperOrigin-RevId: 436317331
Change-Id: I0f8a0c4cd0d5f348a33e486c85c863072c30742a
GitOrigin-RevId: bcd349230e418f5e29d5fced1b942828fa5cb2ad
ARM64EC is a Microsoft-designed ARM64 ABI compatible with AMD64
applications on ARM64 Windows 11. The ARM64EC does not support
_umul128 and __rdtsc as x64 intrinsics, though it provides inline
function implementations for them, by emulation. Since the code
already has portable code paths without using the intrinsics,
instead of using the emulated intrinsic implementations, we use
the said portable code paths for ARM64EC.
--
199bdbf9ad253b216ed6c6386bf69bc706330204 by Abseil Team <absl-team@google.com>:
Import of CCTZ from GitHub.
PiperOrigin-RevId: 435425408
Change-Id: I502d21ca5771d14e24fe41b28dc562ea6274996d
--
245a761e96f53857cef9c2359eac9d4bbcfdfd47 by Abseil Team <absl-team@google.com>:
Fix a -Wsign-compare -Wconversion problem in absl::btree discovered while getting cachelib to compile with those flags enabled.
PiperOrigin-RevId: 435419108
Change-Id: I0a9fa53d0163f678dde8960410315a5bc8445c72
GitOrigin-RevId: 199bdbf9ad253b216ed6c6386bf69bc706330204
--
399d051d30f7a78c367bb1dc08829ffacbb619a6 by Abseil Team <absl-team@google.com>:
Fix a glitch in symbolization which could result in the same address being
correctly symbolized and "(unknown)" in the same crash report.
PiperOrigin-RevId: 435371003
Change-Id: I9f6a5684144be6d3d366584601d79fda9eefdce6
--
5dad813de52773e0bb09c6b2351e1bbadb53deac by Abseil Team <absl-team@google.com>:
Fix ABSL_HAVE_MMAP check in direct_mmap.h
This change makes the check for ABSL_HAVE_MMAP match the other checks
in absl. This fixes builds where ABSL_HAVE_MMAP is not defined.
PiperOrigin-RevId: 435190242
Change-Id: I11638ef315849cafcf4ea1611eee1a98c80e7dcb
GitOrigin-RevId: 399d051d30f7a78c367bb1dc08829ffacbb619a6
--
c49308e5361da572b5accdfe664757ca6bf7fed1 by Derek Mauro <dmauro@google.com>:
Disable TestArmThumbOverlap on platforms that don't support it
TestArmThumbOverlap includes a pair of test functions, one built in
arm mode and the other built in thumb mode.
Unfortunately when configured for armv6 hardfloat, gcc refuses to
build any functions in thumb mode (even if they don't actually use
floating point)
Closes#1112
PiperOrigin-RevId: 435078532
Change-Id: I090623d0f89839a5f9dde831756aba5267c9a45c
GitOrigin-RevId: c49308e5361da572b5accdfe664757ca6bf7fed1
--
5dc885f2b62993bccf33a3f3b99f7e460c819c89 by Derek Mauro <dmauro@google.com>:
Remove the internal-only ABSL_INTERNAL_ASSUME now that ABSL_ASSUME
is available and ABSL_INTERNAL_ASSUME has no more users.
Improve the documentation to ABSL_ASSUME somewhat.
PiperOrigin-RevId: 434803125
Change-Id: I7c27418463ffc1c7e10ecd50e2d17f348f686af7
--
4aea19a0ef596228c9136a4c2446e6f25085f23c by Derek Mauro <dmauro@google.com>:
Update documentation to warn against using absl::Hash across
dynamically loaded libraries
Fixes#1128
PiperOrigin-RevId: 434723247
Change-Id: Ib0c7ba03b2cab98b42e19e85be6833192d4b4067
GitOrigin-RevId: 5dc885f2b62993bccf33a3f3b99f7e460c819c89
--
d3b99682554d339c42556680f4d65f83226005e2 by Martijn Vels <mvels@google.com>:
Inline CycleClock code and remove branch for x86 CycleClockSource function
This CL removes the relaxed load for x86 as there is no acquire price to pay on x86. It inlines the UnscaledCycleClock::Now() which is a single RTDSC op for x86, and likewise inlines CycleClock::Now() for x86. The inlining should mostly have secondary benefits such as reducing spills on outlined calls.
LTO may eventually hoist these functions inline for the hotspots, but it doesn't hurt to default inline this for all builds and let the compiler decide on the first pass.
The perlab benchmark is noisy for the plain BM_Now, but the other benchmarks and the run on my local machine are clear.
------------- Local Benchy Benchmark
name old cpu/op new cpu/op delta
BM_Now 3.41ns ± 1% 2.30ns ± 2% -32.52% (p=0.000 n=50+50)
BM_NowWithRegisterPresure 4.96ns ± 2% 4.19ns ± 2% -15.57% (p=0.000 n=56+55)
BM_NowWithCallback 3.30ns ± 2% 1.91ns ± 2% -42.00% (p=0.000 n=47+60)
------------- Perflab Benchy Benchmark
name old cpu/op new cpu/op delta
BM_Now 8.20ns ±13% 4.32ns ±83% ~ (p=0.413 n=4+5)
BM_NowWithRegisterPresure 7.91ns ± 1% 3.68ns ± 2% -53.45% (p=0.029 n=4+4)
BM_NowWithCallback 2.66ns ±13% 1.58ns ± 0% -40.51% (p=0.008 n=5+5)
PiperOrigin-RevId: 434474766
Change-Id: I991d987ae9233e50f09606c874055cf4c5a56300
--
b38330686a0af176a2679163e4d2fa1b90e2f667 by Laramie Leavitt <lar@google.com>:
Style, comment, and test updates
* Remove a redundant assert in uniform_real_distribution.
* Update comment in internal/generate_real.h
* Style updates to uniform_real_distribution_test
mainly replacing TypeParam with real_type, using aliases for some limits, etc.
* Add a few more minor tests.
PiperOrigin-RevId: 433902174
Change-Id: Id75be8e24be2fb8f6aea05feec13e3ef320a7254
--
ab2da6047ff7f5dae3add3779fcddf73b03feabf by Abseil Team <absl-team@google.com>:
Remove declaration of method whose definition was previously removed.
PiperOrigin-RevId: 433507828
Change-Id: I0130b689813125250f7de2664e767e181f676c89
--
df0c87f4ec2c010691931c1bef9d26470a6e63a2 by Derek Mauro <dmauro@google.com>:
Internal change
PiperOrigin-RevId: 433289136
Change-Id: Iba157dc83ed99dafd17a2223d2504e49f8afbb9e
--
7445fa312f2995772900eda82467325b3401a17d by Martijn Vels <mvels@google.com>:
Optimize CordReader logic now that CONCAT is removed
This CL cleans up various helper functions and logic remaining from previous complex CONCAT logic that is no longer needed, simplifying the CordReader logic.
PiperOrigin-RevId: 433208748
Change-Id: I5f7b1883573c44e7c6f8af12c3cddbd197cb134d
GitOrigin-RevId: d3b99682554d339c42556680f4d65f83226005e2
Abseil Team
Samuel Benzaquen
Benjamin Barenblat
Andy Getzendanner
Evan Brown
Dino Radakovic
Derek Mauro
Fabrice Fontaine
Ren Zibei
Calvin Ke
Ben Niu
Thomas Klausner