Export of internal Abseil changes.

--
f6c627ce4470a814adc377947b58346eef69a4c9 by Jon Cohen <cohenjon@google.com>:

Don't create install rules when Abseil is used as a subdirectory.

Fix #287

PiperOrigin-RevId: 240559825

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a5d9b06fe736143068997988b654b5f66ec3266a by Matt Calabrese <calabrese@google.com>:

Make absl::nullopt an inline constexpr variable, as specified in the standard (with a workaround for pre-c++17 compilers).

PiperOrigin-RevId: 240552286

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d7bee50cff745fbb8d1cdf56a200d9073d311c80 by Abseil Team <absl-team@google.com>:

Internal Change

PiperOrigin-RevId: 240425622

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828dd49d392d83dbeecd9d3e9cb14551ab265905 by Jon Cohen <cohenjon@google.com>:

Add default link options to absl builds.

Currently all this does is add -ignore:4221 to Abseil msvc builds, but the structure is all in place to add more link options when necessary

Fix #277

Note: This CL changes tact for us in that it puts the default options in the helper function as opposed to the invocations of absl_cc_blah.  The original intent of keeping these out of the helper functions was to make generating the CMakeLists.txt files have a smaller diff, but looking now that is a problem for the future, and small compared to making maintenance and use of our CMake buildsystem easier
PiperOrigin-RevId: 240409463

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4aa120e9dcf76d29e9ca0008d0f6d4d9fa8abe8c by Matt Kulukundis <kfm@google.com>:

Reduce flake rate for non-determistic test to < 1/10,000

PiperOrigin-RevId: 240370938

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bc30e219531827bfbf90915b2067c7fb8160bb6d by Derek Mauro <dmauro@google.com>:

Add Bazel caching on Kokoro for new linux targets.

PiperOrigin-RevId: 240356556

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c4e06d79a50d7bb211312b7845c4bd92c0761747 by Jon Cohen <cohenjon@google.com>:

include AbseilInstallDirs instead of GNUInstallDirs.  It worked before because global_CMakeLists.txt also included AbseilInstallDirs

PiperOrigin-RevId: 240206409

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c254dc6cade8a263f3f97fb1417d92fe5235ff32 by Jon Cohen <cohenjon@google.com>:

Fix logic for when we create the variant_exception_safety_test in CMake.  Currently we are only running in on gcc > 4.9, when we want it run on every compiler except gcc <= 4.8

PiperOrigin-RevId: 240194174

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01518006b351d3670ba1d349cfbcb7dd6f3a8b84 by CJ Johnson <johnsoncj@google.com>:

Removes old implementation warning comment now that InlinedVector has an implementation detail file

PiperOrigin-RevId: 240167265

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eb05355ae8c7397752ab7a65afc9e0a99472ba9d by Jon Cohen <cohenjon@google.com>:

Remove the forward declaration of Span

PiperOrigin-RevId: 240156660

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b7e75aa3933d6e79dd086821cf58d15e72f476f4 by Jon Cohen <cohenjon@google.com>:

Prepare CMake install rule for LTS releases:
  * Remove the warning against installing in system install locations
  * Insert versioning to keep different LTS installs from colliding.  Headers are installed in <prefix>/absl_$version/include, .a files in <prefix>/absl_$version/lib, and config files in <prefix>/absl_$version/lib/cmake

PiperOrigin-RevId: 240153986

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de63488ab6236e041f08260794b0b634a2b8ed16 by CJ Johnson <johnsoncj@google.com>:

Reduce reader confusion by using std::addressof(...) even when the type is known to not overload operator&(...)

PiperOrigin-RevId: 240131902
GitOrigin-RevId: f6c627ce4470a814adc377947b58346eef69a4c9
Change-Id: I95dbbacaaf65aceeeca9e9bee5fd9ea456225f62

5 files changed, 46 insertions, 16 deletions

diff --git a/absl/copts/AbseilConfigureCopts.cmake b/absl/copts/AbseilConfigureCopts.cmake
index 5084958c3581..b2b3f88d5055 100644
--- a/absl/copts/AbseilConfigureCopts.cmake
+++ b/absl/copts/AbseilConfigureCopts.cmake
@@ -3,6 +3,7 @@ include(GENERATED_AbseilCopts)
 
 set(ABSL_LSAN_LINKOPTS "")
 set(ABSL_HAVE_LSAN OFF)
+set(ABSL_DEFAULT_LINKOPTS "")
 
 if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "GNU")
   set(ABSL_DEFAULT_COPTS "${ABSL_GCC_FLAGS}")
@@ -19,6 +20,7 @@ elseif("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang")
     set(ABSL_DEFAULT_COPTS "${ABSL_LLVM_FLAGS}")
     set(ABSL_TEST_COPTS "${ABSL_LLVM_FLAGS};${ABSL_LLVM_TEST_FLAGS}")
     set(ABSL_EXCEPTIONS_FLAG "${ABSL_LLVM_EXCEPTIONS_FLAGS}")
+    set(ABSL_DEFAULT_LINKOPTS "${ABSL_MSVC_LINKOPTS}")
     if ("${CMAKE_CXX_COMPILER_ID}" STREQUAL "Clang")
       # AppleClang doesn't have lsan
       # https://developer.apple.com/documentation/code_diagnostics
@@ -32,6 +34,7 @@ elseif("${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")
   set(ABSL_DEFAULT_COPTS "${ABSL_MSVC_FLAGS}")
   set(ABSL_TEST_COPTS "${ABSL_MSVC_FLAGS};${ABSL_MSVC_TEST_FLAGS}")
   set(ABSL_EXCEPTIONS_FLAG "${ABSL_MSVC_EXCEPTIONS_FLAGS}")
+  set(ABSL_DEFAULT_LINKOPTS "${ABSL_MSVC_LINKOPTS}")
 else()
   message(WARNING "Unknown compiler: ${CMAKE_CXX_COMPILER}.  Building with no default flags")
   set(ABSL_DEFAULT_COPTS "")
diff --git a/absl/copts/GENERATED_AbseilCopts.cmake b/absl/copts/GENERATED_AbseilCopts.cmake
index 9031bfa5daf7..043c88a2f576 100644
--- a/absl/copts/GENERATED_AbseilCopts.cmake
+++ b/absl/copts/GENERATED_AbseilCopts.cmake
@@ -201,6 +201,10 @@ list(APPEND ABSL_MSVC_FLAGS
     "/wd4800"
 )
 
+list(APPEND ABSL_MSVC_LINKOPTS
+    "-ignore:4221"
+)
+
 list(APPEND ABSL_MSVC_TEST_FLAGS
     "/wd4018"
     "/wd4101"
diff --git a/absl/copts/GENERATED_copts.bzl b/absl/copts/GENERATED_copts.bzl
index e05a58e39b40..d40380b86057 100644
--- a/absl/copts/GENERATED_copts.bzl
+++ b/absl/copts/GENERATED_copts.bzl
@@ -202,6 +202,10 @@ ABSL_MSVC_FLAGS = [
     "/wd4800",
 ]
 
+ABSL_MSVC_LINKOPTS = [
+    "-ignore:4221",
+]
+
 ABSL_MSVC_TEST_FLAGS = [
     "/wd4018",
     "/wd4101",
diff --git a/absl/copts/configure_copts.bzl b/absl/copts/configure_copts.bzl
index 1655addd2461..0015931762a4 100644
--- a/absl/copts/configure_copts.bzl
+++ b/absl/copts/configure_copts.bzl
@@ -14,6 +14,7 @@ load(
     "ABSL_LLVM_TEST_FLAGS",
     "ABSL_MSVC_EXCEPTIONS_FLAGS",
     "ABSL_MSVC_FLAGS",
+    "ABSL_MSVC_LINKOPTS",
     "ABSL_MSVC_TEST_FLAGS",
 )
 
@@ -40,3 +41,8 @@ ABSL_EXCEPTIONS_FLAG = select({
 ABSL_EXCEPTIONS_FLAG_LINKOPTS = select({
     "//conditions:default": [],
 })
+
+ABSL_DEFAULT_LINKOPTS = select({
+    "//absl:windows": ABSL_MSVC_LINKOPTS,
+    "//conditions:default": [],
+})
diff --git a/absl/copts/copts.py b/absl/copts/copts.py
index 3c9d42945f1b..608d7c0edeee 100644
--- a/absl/copts/copts.py
+++ b/absl/copts/copts.py
@@ -153,26 +153,39 @@ COPT_VARS = {
         "-Wno-unused-private-field",
     ],
     "ABSL_GCC_EXCEPTIONS_FLAGS": ["-fexceptions"],
-    "ABSL_LLVM_FLAGS": LLVM_BIG_WARNING_FLAGS + LLVM_DISABLE_WARNINGS_FLAGS,
-    "ABSL_LLVM_TEST_FLAGS": LLVM_TEST_DISABLE_WARNINGS_FLAGS,
+    "ABSL_LLVM_FLAGS":
+        LLVM_BIG_WARNING_FLAGS + LLVM_DISABLE_WARNINGS_FLAGS,
+    "ABSL_LLVM_TEST_FLAGS":
+        LLVM_TEST_DISABLE_WARNINGS_FLAGS,
     "ABSL_LLVM_EXCEPTIONS_FLAGS": ["-fexceptions"],
-    "ABSL_CLANG_CL_FLAGS": (MSVC_BIG_WARNING_FLAGS +
-                            LLVM_DISABLE_WARNINGS_FLAGS + MSVC_DEFINES),
-    "ABSL_CLANG_CL_TEST_FLAGS": LLVM_TEST_DISABLE_WARNINGS_FLAGS,
-    "ABSL_CLANG_CL_EXCEPTIONS_FLAGS": MSVC_STYLE_EXCEPTIONS_FLAGS,
-    "ABSL_MSVC_FLAGS": MSVC_BIG_WARNING_FLAGS + MSVC_DEFINES + [
-        "/wd4005",  # macro-redefinition
-        "/wd4068",  # unknown pragma
-        "/wd4180",  # qualifier applied to function type has no meaning; ignored
-        "/wd4244",  # conversion from 'type1' to 'type2', possible loss of data
-        "/wd4267",  # conversion from 'size_t' to 'type', possible loss of data
-        # forcing value to bool 'true' or 'false' (performance warning)
-        "/wd4800",
-    ],
+    "ABSL_CLANG_CL_FLAGS": (
+        MSVC_BIG_WARNING_FLAGS + LLVM_DISABLE_WARNINGS_FLAGS + MSVC_DEFINES),
+    "ABSL_CLANG_CL_TEST_FLAGS":
+        LLVM_TEST_DISABLE_WARNINGS_FLAGS,
+    "ABSL_CLANG_CL_EXCEPTIONS_FLAGS":
+        MSVC_STYLE_EXCEPTIONS_FLAGS,
+    "ABSL_MSVC_FLAGS":
+        MSVC_BIG_WARNING_FLAGS + MSVC_DEFINES + [
+            "/wd4005",  # macro-redefinition
+            "/wd4068",  # unknown pragma
+            # qualifier applied to function type has no meaning; ignored
+            "/wd4180",
+            # conversion from 'type1' to 'type2', possible loss of data
+            "/wd4244",
+            # conversion from 'size_t' to 'type', possible loss of data
+            "/wd4267",
+            # forcing value to bool 'true' or 'false' (performance warning)
+            "/wd4800",
+        ],
     "ABSL_MSVC_TEST_FLAGS": [
         "/wd4018",  # signed/unsigned mismatch
         "/wd4101",  # unreferenced local variable
         "/wd4503",  # decorated name length exceeded, name was truncated
     ],
-    "ABSL_MSVC_EXCEPTIONS_FLAGS": MSVC_STYLE_EXCEPTIONS_FLAGS,
+    "ABSL_MSVC_EXCEPTIONS_FLAGS":
+        MSVC_STYLE_EXCEPTIONS_FLAGS,
+    "ABSL_MSVC_LINKOPTS": [
+        # Object file doesn't export any previously undefined symbols
+        "/ignore:4221",
+    ],
 }