Export of internal Abseil changes

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4fc38390e66394e51ef4637ca0778f929017b4c8 by Gennadiy Rozental <rogeeff@google.com>:

Internal Change

PiperOrigin-RevId: 321020681

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880d1c1cb7590e7265e21afe32edde473ef830d4 by Derek Mauro <dmauro@google.com>:

Decrease number of threads in thread_identity_test to hopefully
prevent test timeouts

PiperOrigin-RevId: 321019403
GitOrigin-RevId: 4fc38390e66394e51ef4637ca0778f929017b4c8
Change-Id: Id8175bae6e490277d663d76fff9c06353b8c7f05

CMakeLists.txt

@@ -30,6 +30,9 @@ cmake_policy(SET CMP0057 NEW)
 # Project version variables are the empty string if version is unspecified
 cmake_policy(SET CMP0048 NEW)
 
+# option() honor variables
+cmake_policy(SET CMP0077 NEW)
+
 project(absl CXX)
 
 # Output directory is correct by default for most build setups. However, when
@@ -41,9 +44,9 @@ set(CMAKE_RUNTIME_OUTPUT_DIRECTORY ${CMAKE_BINARY_DIR}/bin)
 # when absl is included as subproject (i.e. using add_subdirectory(abseil-cpp))
 # in the source tree of a project that uses it, install rules are disabled.
 if(NOT "^${CMAKE_SOURCE_DIR}$" STREQUAL "^${PROJECT_SOURCE_DIR}$")
-  set(ABSL_ENABLE_INSTALL FALSE)
+  option(ABSL_ENABLE_INSTALL "Enable install rule" OFF)
 else()
-  set(ABSL_ENABLE_INSTALL TRUE)
+  option(ABSL_ENABLE_INSTALL "Enable install rule" ON)
 endif()
 
 list(APPEND CMAKE_MODULE_PATH

absl/base/internal/thread_identity_test.cc

@@ -75,7 +75,7 @@ TEST(ThreadIdentityTest, BasicIdentityWorksThreaded) {
   // - If a thread implementation chooses to recycle threads, that
   //   correct re-initialization occurs.
   static const int kNumLoops = 3;
-  static const int kNumThreads = 400;
+  static const int kNumThreads = 32;
   for (int iter = 0; iter < kNumLoops; iter++) {
     std::vector<std::thread> threads;
     for (int i = 0; i < kNumThreads; ++i) {