Export of internal Abseil changes.

--
1c1d6e2404dfc6caa022b335df5acdac6da50fe1 by Derek Mauro <dmauro@google.com>:

Fix the internal namespacing in unaligned_access.h

PiperOrigin-RevId: 215434506

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17d4400aebf025a230690fc1c7a968ef8d85bbba by Eric Fiselier <ericwf@google.com>:

gtest depends on the GCC extension allowing variadic macros
to be passed a empty parameter pack for ..., but LLVM diagnoses
this as a GNU extension.

This patch suppresses the warning when building the absl tests.

PiperOrigin-RevId: 215426161

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f2c49dde23a9f445b9de963f1bbe840ebb568b30 by Eric Fiselier <ericwf@google.com>:

Use EXPECT_DEATH_IF_SUPPORTED instead of EXPECT_DEATH.

This avoids breaking the test when gtest doesn't support
death tests.

PiperOrigin-RevId: 215423849

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cd687c1e121709603f4fc3726b534f6a9c52cc89 by Eric Fiselier <ericwf@google.com>:

Disable LLVM's -Wmissing-variable-declarations in tests.

GCC's configuration already disables this via -Wno-missing-declarations,
this change makes LLVM do the same.

The warning would otherwise flag most tests which use ABSL_FLAG.

PiperOrigin-RevId: 215407429

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d14098824c84e3a8c8f6fb920e0335fb48fe2010 by Eric Fiselier <ericwf@google.com>:

Fix local variable shadowing in city hash implementation.

PiperOrigin-RevId: 215407249

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4b5e140ba743f0d231790a26c49083abb4329e2c by Abseil Team <absl-team@google.com>:

Make raw_hash_set::reserve 2X fast when reserve doesn't do any allocation.
Make raw_hash_set::reserve ~1% faster when reserve does some (128~4k) allocation.

PiperOrigin-RevId: 215348727

--
461161e65e04b801480aa117af2534c594654ccf by Eric Fiselier <ericwf@google.com>:

Internal change

PiperOrigin-RevId: 215272283

--
50413ae31ad3d3a177257416acd8ede47a17bff2 by Eric Fiselier <ericwf@google.com>:

Internal Change

PiperOrigin-RevId: 215233183

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477be54c43d61019a8fe4e190e340eb52737d383 by Abseil Team <absl-team@google.com>:

Clarify misleading comment on ABSL_ATTRIBUTE_UNUSED

PiperOrigin-RevId: 215185496

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2cafa2b5287507d3a946682aee9ab13af6d471c9 by Matt Kulukundis <kfm@google.com>:

Add support for absl::Hash to various absl in types.

PiperOrigin-RevId: 215039569

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082248901991aa3d29be0ea3689c7f213cf0fd83 by Derek Mauro <dmauro@google.com>:

Remove an instance of HAS_GLOBAL_STRING from hash_function_defaults.h

PiperOrigin-RevId: 214989094

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b929f61907f0786a6133e3a9d7287e339c0a0acb by Derek Mauro <dmauro@google.com>:

Internal import of Github #174
Fix code snippet in comment
https://github.com/abseil/abseil-cpp/pull/174

PiperOrigin-RevId: 214958849

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f2c5e829eca11c352e121f56eefbf87083305023 by Derek Mauro <dmauro@google.com>:

Internal import of GitHub #173
Fix CMake build for absl::container.
https://github.com/abseil/abseil-cpp/pull/173

PiperOrigin-RevId: 214957796

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d704f860f9fddafb99e34e6c5032e49f73874e10 by Abseil Team <absl-team@google.com>:

Internal change

PiperOrigin-RevId: 214828181
GitOrigin-RevId: 1c1d6e2404dfc6caa022b335df5acdac6da50fe1
Change-Id: I551de2b1ba0cbaf6856cd5959358cf6651179dea

1 files changed, 13 insertions, 12 deletions

diff --git a/absl/hash/internal/city.cc b/absl/hash/internal/city.cc
index 591017ab..8f72dd1b 100644
--- a/absl/hash/internal/city.cc
+++ b/absl/hash/internal/city.cc
@@ -129,6 +129,7 @@ uint32_t CityHash32(const char *s, size_t len) {
 
   // len > 24
   uint32_t h = len, g = c1 * len, f = g;
+
   uint32_t a0 = Rotate32(Fetch32(s + len - 4) * c1, 17) * c2;
   uint32_t a1 = Rotate32(Fetch32(s + len - 8) * c1, 17) * c2;
   uint32_t a2 = Rotate32(Fetch32(s + len - 16) * c1, 17) * c2;
@@ -151,28 +152,28 @@ uint32_t CityHash32(const char *s, size_t len) {
   f = f * 5 + 0xe6546b64;
   size_t iters = (len - 1) / 20;
   do {
-    uint32_t a0 = Rotate32(Fetch32(s) * c1, 17) * c2;
-    uint32_t a1 = Fetch32(s + 4);
-    uint32_t a2 = Rotate32(Fetch32(s + 8) * c1, 17) * c2;
-    uint32_t a3 = Rotate32(Fetch32(s + 12) * c1, 17) * c2;
-    uint32_t a4 = Fetch32(s + 16);
-    h ^= a0;
+    uint32_t b0 = Rotate32(Fetch32(s) * c1, 17) * c2;
+    uint32_t b1 = Fetch32(s + 4);
+    uint32_t b2 = Rotate32(Fetch32(s + 8) * c1, 17) * c2;
+    uint32_t b3 = Rotate32(Fetch32(s + 12) * c1, 17) * c2;
+    uint32_t b4 = Fetch32(s + 16);
+    h ^= b0;
     h = Rotate32(h, 18);
     h = h * 5 + 0xe6546b64;
-    f += a1;
+    f += b1;
     f = Rotate32(f, 19);
     f = f * c1;
-    g += a2;
+    g += b2;
     g = Rotate32(g, 18);
     g = g * 5 + 0xe6546b64;
-    h ^= a3 + a1;
+    h ^= b3 + b1;
     h = Rotate32(h, 19);
     h = h * 5 + 0xe6546b64;
-    g ^= a4;
+    g ^= b4;
     g = absl::gbswap_32(g) * 5;
-    h += a4 * 5;
+    h += b4 * 5;
     h = absl::gbswap_32(h);
-    f += a0;
+    f += b0;
     PERMUTE3(f, h, g);
     s += 20;
   } while (--iters != 0);