Export of internal Abseil changes.

--
22fceefcf070a0cf89bf1846bee16a9d36ad4161 by Derek Mauro <dmauro@google.com>:

Use function static for once initialization of flag registry.

This is a workaround for the MSVC debug constexpr initialization issue
in absl::once_flag.

GitHub #304

PiperOrigin-RevId: 248169007

--
97bbe6a5233802b61e758c55f7ba8926539cc4ca by Chris Kennelly <ckennelly@google.com>:

Internal change

PiperOrigin-RevId: 248139347

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e72640ee079b9fa44e2c7f925fa0a608bcfea515 by Derek Mauro <dmauro@google.com>:

Re-write flags config. It doesn't have to be written in the convoluted
way it currently is in the opensource-only code path.

PiperOrigin-RevId: 248010502

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2a72552511b8086c78cb43012c1644e519b3807e by Abseil Team <absl-team@google.com>:

Handle pthread_getschedparam() failure.

Log an error message if pthread_getschedparam() fails.

In Android's Media Framework, libminijail (which I believe is a sandbox)
aborts the process if pthread_getschedparam() is called:

  media.swcodec: libminijail[7526]: blocked syscall: sched_getparam
  ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  /system/bin/tombstoned: received crash request for pid 7526

Although this CL cannot handle that extreme failure mode, it handles an
error return from pthread_getschedparam() and won't use the uninitialized
param.sched_priority value in that case.

PiperOrigin-RevId: 247999953

--
bb154a92be37987d00d652c7c792594f2f515d83 by Abseil Team <absl-team@google.com>:

Allow intrinsic int128 to be set for __aarch64__ targets.

PiperOrigin-RevId: 247977594
GitOrigin-RevId: 22fceefcf070a0cf89bf1846bee16a9d36ad4161
Change-Id: I1f7ccfd82eb71446277a8e6f542fe835ac173d71

1 files changed, 9 insertions, 5 deletions

diff --git a/absl/synchronization/mutex.cc b/absl/synchronization/mutex.cc
index 3e8033a0..76bd307a 100644
--- a/absl/synchronization/mutex.cc
+++ b/absl/synchronization/mutex.cc
@@ -901,11 +901,15 @@ static PerThreadSynch *Enqueue(PerThreadSynch *head,
       // base_internal::CycleClock::Now() is 0.5%.
       int policy;
       struct sched_param param;
-      pthread_getschedparam(pthread_self(), &policy, &param);
-      s->priority = param.sched_priority;
-      s->next_priority_read_cycles =
-          now_cycles +
-          static_cast<int64_t>(base_internal::CycleClock::Frequency());
+      const int err = pthread_getschedparam(pthread_self(), &policy, &param);
+      if (err != 0) {
+        ABSL_RAW_LOG(ERROR, "pthread_getschedparam failed: %d", err);
+      } else {
+        s->priority = param.sched_priority;
+        s->next_priority_read_cycles =
+            now_cycles +
+            static_cast<int64_t>(base_internal::CycleClock::Frequency());
+      }
     }
     if (s->priority > head->priority) {  // s's priority is above head's
       // try to put s in priority-fifo order, or failing that at the front.