Export of internal Abseil changes.

--
ffe43f972f956e3f9a8fb7b68993d243ba8f79fb by Abseil Team <absl-team@google.com>:

Replace usage of soon-to-be-deprecated http_archive rule with Skylark equivalent
https://github.com/abseil/abseil-cpp/pull/138

PiperOrigin-RevId: 204939972

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24021d7aec96ed013333760fba590eba5a9ddf63 by Abseil Team <absl-team@google.com>:

Remove incorrect constraint that StrSplit only works on std::strings; rather, it works on anything string-like.

PiperOrigin-RevId: 204761431

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ce61d3b0ac163caa1156817f3d1a997d9376a3f3 by Derek Mauro <dmauro@google.com>:

Support s390/s390x in examine_stack.cc (GitHub issue #135).
This is UNTESTED (no machine to test on).

PiperOrigin-RevId: 204756692

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68ecab659a95d713c4342fe9e8008c4cdf6abfc1 by Derek Mauro <dmauro@google.com>:

Update WORKSPACE.bazel Gogole Test dependency, remove the unused RE2 dependency.

PiperOrigin-RevId: 204741814

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891e185522f0934e3b48a75617be5fc859d75dbd by Derek Mauro <dmauro@google.com>:

Fix endian_test.cc on big endian platforms.
GitHub issue #135

PiperOrigin-RevId: 204738726

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9becfa12fbb525cd97e5695b94677bd3ea3f61b0 by Abseil Team <absl-team@google.com>:

Improve error messages in absl::variant by splitting up the conditions in the valid type static_assert.

This makes it slightly easier to determine what type is causing issues.

PiperOrigin-RevId: 204508430
GitOrigin-RevId: ffe43f972f956e3f9a8fb7b68993d243ba8f79fb
Change-Id: Icc5e4e8cd1a4cea98dfbed794cd992b734812e1d

4 files changed, 21 insertions, 28 deletions

diff --git a/absl/base/internal/endian_test.cc b/absl/base/internal/endian_test.cc
index f3ff4b39..e2769155 100644
--- a/absl/base/internal/endian_test.cc
+++ b/absl/base/internal/endian_test.cc
@@ -33,32 +33,16 @@ const uint16_t k16Value{0x0123};
 const int kNumValuesToTest = 1000000;
 const int kRandomSeed = 12345;
 
-#ifdef ABSL_IS_BIG_ENDIAN
+#if defined(ABSL_IS_BIG_ENDIAN)
 const uint64_t kInitialInNetworkOrder{kInitialNumber};
 const uint64_t k64ValueLE{0xefcdab8967452301};
 const uint32_t k32ValueLE{0x67452301};
 const uint16_t k16ValueLE{0x2301};
-const uint8_t k8ValueLE{k8Value};
-const uint64_t k64IValueLE{0xefcdab89674523a1};
-const uint32_t k32IValueLE{0x67452391};
-const uint16_t k16IValueLE{0x85ff};
-const uint8_t k8IValueLE{0xff};
-const uint64_t kDoubleValueLE{0x6e861bf0f9210940};
-const uint32_t kFloatValueLE{0xd00f4940};
-const uint8_t kBoolValueLE{0x1};
 
 const uint64_t k64ValueBE{kInitialNumber};
 const uint32_t k32ValueBE{k32Value};
 const uint16_t k16ValueBE{k16Value};
-const uint8_t k8ValueBE{k8Value};
-const uint64_t k64IValueBE{0xa123456789abcdef};
-const uint32_t k32IValueBE{0x91234567};
-const uint16_t k16IValueBE{0xff85};
-const uint8_t k8IValueBE{0xff};
-const uint64_t kDoubleValueBE{0x400921f9f01b866e};
-const uint32_t kFloatValueBE{0x40490fd0};
-const uint8_t kBoolValueBE{0x1};
-#elif defined ABSL_IS_LITTLE_ENDIAN
+#elif defined(ABSL_IS_LITTLE_ENDIAN)
 const uint64_t kInitialInNetworkOrder{0xefcdab8967452301};
 const uint64_t k64ValueLE{kInitialNumber};
 const uint32_t k32ValueLE{k32Value};
diff --git a/absl/debugging/internal/examine_stack.cc b/absl/debugging/internal/examine_stack.cc
index 8434709f..faf88836 100644
--- a/absl/debugging/internal/examine_stack.cc
+++ b/absl/debugging/internal/examine_stack.cc
@@ -52,6 +52,10 @@ void* GetProgramCounter(void* vuc) {
     return reinterpret_cast<void*>(context->uc_mcontext.gp_regs[32]);
 #elif defined(__powerpc__)
     return reinterpret_cast<void*>(context->uc_mcontext.regs->nip);
+#elif defined(__s390__) && !defined(__s390x__)
+    return reinterpret_cast<void*>(context->uc_mcontext.psw.addr & 0x7fffffff);
+#elif defined(__s390__) && defined(__s390x__)
+    return reinterpret_cast<void*>(context->uc_mcontext.psw.addr);
 #elif defined(__x86_64__)
     if (16 < ABSL_ARRAYSIZE(context->uc_mcontext.gregs))
       return reinterpret_cast<void*>(context->uc_mcontext.gregs[16]);
diff --git a/absl/strings/str_split.h b/absl/strings/str_split.h
index 1f089b93..9a7be2b0 100644
--- a/absl/strings/str_split.h
+++ b/absl/strings/str_split.h
@@ -373,11 +373,11 @@ struct SkipWhitespace {
 
 // StrSplit()
 //
-// Splits a given `std::string` based on the provided `Delimiter` object,
-// returning the elements within the type specified by the caller. Optionally,
-// you may also pass a `Predicate` to `StrSplit()` indicating whether to include
-// or exclude the resulting element within the final result set. (See the
-// overviews for Delimiters and Predicates above.)
+// Splits a given std::string based on the provided `Delimiter` object, returning the
+// elements within the type specified by the caller. Optionally, you may pass a
+// `Predicate` to `StrSplit()` indicating whether to include or exclude the
+// resulting element within the final result set. (See the overviews for
+// Delimiters and Predicates above.)
 //
 // Example:
 //
diff --git a/absl/types/variant.h b/absl/types/variant.h
index 9d98a9ed..17e0634d 100644
--- a/absl/types/variant.h
+++ b/absl/types/variant.h
@@ -449,14 +449,19 @@ constexpr bool operator!=(monostate, monostate) noexcept { return false; }
 //------------------------------------------------------------------------------
 template <typename T0, typename... Tn>
 class variant<T0, Tn...> : private variant_internal::VariantBase<T0, Tn...> {
+  static_assert(absl::conjunction<std::is_object<T0>,
+                                  std::is_object<Tn>...>::value,
+                "Attempted to instantiate a variant containing a non-object "
+                "type.");
   // Intentionally not qualifing `negation` with `absl::` to work around a bug
   // in MSVC 2015 with inline namespace and variadic template.
-  static_assert(absl::conjunction<std::is_object<T0>, std::is_object<Tn>...,
-                                  negation<std::is_array<T0> >,
-                                  negation<std::is_array<Tn> >...,
-                                  std::is_nothrow_destructible<T0>,
+  static_assert(absl::conjunction<negation<std::is_array<T0> >,
+                                  negation<std::is_array<Tn> >...>::value,
+                "Attempted to instantiate a variant containing an array type.");
+  static_assert(absl::conjunction<std::is_nothrow_destructible<T0>,
                                   std::is_nothrow_destructible<Tn>...>::value,
-                "Attempted to instantiate a variant with an unsupported type.");
+                "Attempted to instantiate a variant containing a non-nothrow "
+                "destructible type.");
 
   friend struct variant_internal::VariantCoreAccess;