Export of internal Abseil changes

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13b7cb0eff8fda5127193e11dbe0b8655415b512 by Gennadiy Rozental <rogeeff@google.com>:

Change the preprocessor guards to properly exclude tests which does not build on older
version on libstdc++.

Fixes #731

PiperOrigin-RevId: 319987618

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ab2155855b4dd1259a3dd9f48fbb5e6e8c2ccd3f by Derek Mauro <dmauro@google.com>:

Update clang-latest container to LLVM 052e1e0cfd9, Bazel 3.3.1, and CMake 3.17.3

PiperOrigin-RevId: 319835484

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7554283733c309649a05b7f1891b2593e50f07b7 by Abseil Team <absl-team@google.com>:

Implement support for LOAD segments that don't start at p_vaddr==0.

PiperOrigin-RevId: 319694669
GitOrigin-RevId: 13b7cb0eff8fda5127193e11dbe0b8655415b512
Change-Id: I220c2af4169cf8e4dad20cb372589ec7def0e018

1 files changed, 6 insertions, 3 deletions

diff --git a/absl/container/btree_test.cc b/absl/container/btree_test.cc
index 1738d291..c5808074 100644
--- a/absl/container/btree_test.cc
+++ b/absl/container/btree_test.cc
@@ -2463,9 +2463,12 @@ TEST(Btree,
   EXPECT_THAT(s2, ElementsAre(IsEmpty(), ElementsAre(IsNull())));
 }
 
-// GCC 4.9 has a bug in the std::pair constructors that prevents explicit
-// conversions between pair types.
-#if defined(__clang__) || !defined(__GNUC__) || __GNUC__ >= 5
+// libstdc++ included with GCC 4.9 has a bug in the std::pair constructors that
+// prevents explicit conversions between pair types.
+// We only run this test for the libstdc++ from GCC 7 or newer because we can't
+// reliably check the libstdc++ version prior to that release.
+#if !defined(__GLIBCXX__) || \
+    (defined(_GLIBCXX_RELEASE) && _GLIBCXX_RELEASE >= 7)
 TEST(Btree, MapRangeConstructorAndInsertSupportExplicitConversionComparable) {
   const std::pair<absl::string_view, int> names[] = {{"n1", 1}, {"n2", 2}};