Abseil LTS 2020092320200923

What's New:
* `absl::StatusOr<T>` has been released. See our [blog
  post](https://abseil.io/blog/2020-091021-status) for more
  information.
* Abseil Flags reflection interfaces have been released.
* Abseil Flags memory usage has been significantly optimized.
* Abseil now supports a "hardened" build mode. This build mode enables
  runtime checks that guard against programming errors that may lead
  to security vulnerabilities.

Notable Fixes:
* Sanitizer dynamic annotations like `AnnotateRWLockCreate` that are
  also defined by the compiler sanitizer implementation are no longer
  also defined by Abseil.
* Sanitizer macros are now prefixed with `ABSL_` to avoid naming collisions.
* Sanitizer usage is now automatically detected and no longer requires
  macros like `ADDRESS_SANITIZER` to be defined on the command line.

Breaking Changes:
* Abseil no longer contains a `dynamic_annotations` library. Users
  using a supported build system (Bazel or CMake) are unaffected by
  this, but users manually specifying link libraries may get an error
  about a missing linker input.

Baseline: 7680a5f8efe32de4753baadbd63e74e59d95bac1
Cherry picks: None

1 files changed, 12 insertions, 3 deletions

diff --git a/absl/random/uniform_int_distribution_test.cc b/absl/random/uniform_int_distribution_test.cc
index aacff88d..276d72ad 100644
--- a/absl/random/uniform_int_distribution_test.cc
+++ b/absl/random/uniform_int_distribution_test.cc
@@ -26,6 +26,7 @@
 #include "absl/base/internal/raw_logging.h"
 #include "absl/random/internal/chi_square.h"
 #include "absl/random/internal/distribution_test_util.h"
+#include "absl/random/internal/pcg_engine.h"
 #include "absl/random/internal/sequence_urbg.h"
 #include "absl/random/random.h"
 #include "absl/strings/str_cat.h"
@@ -123,7 +124,7 @@ TYPED_TEST(UniformIntDistributionTest, ViolatesPreconditionsDeathTest) {
   absl::uniform_int_distribution<TypeParam> dist(10, 1);
   auto x = dist(gen);
 
-  // Any value will generate a non-empty std::string.
+  // Any value will generate a non-empty string.
   EXPECT_FALSE(absl::StrCat(+x).empty()) << x;
 #endif  // NDEBUG
 }
@@ -134,7 +135,11 @@ TYPED_TEST(UniformIntDistributionTest, TestMoments) {
   using param_type =
       typename absl::uniform_int_distribution<TypeParam>::param_type;
 
-  absl::InsecureBitGen rng;
+  // We use a fixed bit generator for distribution accuracy tests.  This allows
+  // these tests to be deterministic, while still testing the qualify of the
+  // implementation.
+  absl::random_internal::pcg64_2018_engine rng{0x2B7E151628AED2A6};
+
   std::vector<double> values(kSize);
   for (const auto& param :
        {param_type(0, Limits::max()), param_type(13, 127)}) {
@@ -178,7 +183,11 @@ TYPED_TEST(UniformIntDistributionTest, ChiSquaredTest50) {
   const TypeParam min = std::is_unsigned<TypeParam>::value ? 37 : -37;
   const TypeParam max = min + kBuckets;
 
-  absl::InsecureBitGen rng;
+  // We use a fixed bit generator for distribution accuracy tests.  This allows
+  // these tests to be deterministic, while still testing the qualify of the
+  // implementation.
+  absl::random_internal::pcg64_2018_engine rng{0x2B7E151628AED2A6};
+
   absl::uniform_int_distribution<TypeParam> dist(min, max);
 
   std::vector<int32_t> counts(kBuckets + 1, 0);