Squashed 'third_party/google-benchmark/' content from commit 785e2c3
Change-Id: Iaaca5eca89f717081452e643a233e86425b03e89
git-subtree-dir: third_party/google-benchmark
git-subtree-split: 785e2c3158589e8ef48c59ba80e48d76bdbd8902
diff --git a/cmake/AddCXXCompilerFlag.cmake b/cmake/AddCXXCompilerFlag.cmake
new file mode 100644
index 0000000..d0d2099
--- /dev/null
+++ b/cmake/AddCXXCompilerFlag.cmake
@@ -0,0 +1,74 @@
+# - Adds a compiler flag if it is supported by the compiler
+#
+# This function checks that the supplied compiler flag is supported and then
+# adds it to the corresponding compiler flags
+#
+# add_cxx_compiler_flag(<FLAG> [<VARIANT>])
+#
+# - Example
+#
+# include(AddCXXCompilerFlag)
+# add_cxx_compiler_flag(-Wall)
+# add_cxx_compiler_flag(-no-strict-aliasing RELEASE)
+# Requires CMake 2.6+
+
+if(__add_cxx_compiler_flag)
+ return()
+endif()
+set(__add_cxx_compiler_flag INCLUDED)
+
+include(CheckCXXCompilerFlag)
+
+function(mangle_compiler_flag FLAG OUTPUT)
+ string(TOUPPER "HAVE_CXX_FLAG_${FLAG}" SANITIZED_FLAG)
+ string(REPLACE "+" "X" SANITIZED_FLAG ${SANITIZED_FLAG})
+ string(REGEX REPLACE "[^A-Za-z_0-9]" "_" SANITIZED_FLAG ${SANITIZED_FLAG})
+ string(REGEX REPLACE "_+" "_" SANITIZED_FLAG ${SANITIZED_FLAG})
+ set(${OUTPUT} "${SANITIZED_FLAG}" PARENT_SCOPE)
+endfunction(mangle_compiler_flag)
+
+function(add_cxx_compiler_flag FLAG)
+ mangle_compiler_flag("${FLAG}" MANGLED_FLAG)
+ set(OLD_CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS}")
+ set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} ${FLAG}")
+ check_cxx_compiler_flag("${FLAG}" ${MANGLED_FLAG})
+ set(CMAKE_REQUIRED_FLAGS "${OLD_CMAKE_REQUIRED_FLAGS}")
+ if(${MANGLED_FLAG})
+ set(VARIANT ${ARGV1})
+ if(ARGV1)
+ string(TOUPPER "_${VARIANT}" VARIANT)
+ endif()
+ set(CMAKE_CXX_FLAGS${VARIANT} "${CMAKE_CXX_FLAGS${VARIANT}} ${BENCHMARK_CXX_FLAGS${VARIANT}} ${FLAG}" PARENT_SCOPE)
+ endif()
+endfunction()
+
+function(add_required_cxx_compiler_flag FLAG)
+ mangle_compiler_flag("${FLAG}" MANGLED_FLAG)
+ set(OLD_CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS}")
+ set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} ${FLAG}")
+ check_cxx_compiler_flag("${FLAG}" ${MANGLED_FLAG})
+ set(CMAKE_REQUIRED_FLAGS "${OLD_CMAKE_REQUIRED_FLAGS}")
+ if(${MANGLED_FLAG})
+ set(VARIANT ${ARGV1})
+ if(ARGV1)
+ string(TOUPPER "_${VARIANT}" VARIANT)
+ endif()
+ set(CMAKE_CXX_FLAGS${VARIANT} "${CMAKE_CXX_FLAGS${VARIANT}} ${FLAG}" PARENT_SCOPE)
+ set(CMAKE_EXE_LINKER_FLAGS "${CMAKE_EXE_LINKER_FLAGS} ${FLAG}" PARENT_SCOPE)
+ set(CMAKE_SHARED_LINKER_FLAGS "${CMAKE_SHARED_LINKER_FLAGS} ${FLAG}" PARENT_SCOPE)
+ set(CMAKE_MODULE_LINKER_FLAGS "${CMAKE_MODULE_LINKER_FLAGS} ${FLAG}" PARENT_SCOPE)
+ set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} ${FLAG}" PARENT_SCOPE)
+ else()
+ message(FATAL_ERROR "Required flag '${FLAG}' is not supported by the compiler")
+ endif()
+endfunction()
+
+function(check_cxx_warning_flag FLAG)
+ mangle_compiler_flag("${FLAG}" MANGLED_FLAG)
+ set(OLD_CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS}")
+ # Add -Werror to ensure the compiler generates an error if the warning flag
+ # doesn't exist.
+ set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -Werror ${FLAG}")
+ check_cxx_compiler_flag("${FLAG}" ${MANGLED_FLAG})
+ set(CMAKE_REQUIRED_FLAGS "${OLD_CMAKE_REQUIRED_FLAGS}")
+endfunction()
diff --git a/cmake/CXXFeatureCheck.cmake b/cmake/CXXFeatureCheck.cmake
new file mode 100644
index 0000000..99b56dd
--- /dev/null
+++ b/cmake/CXXFeatureCheck.cmake
@@ -0,0 +1,64 @@
+# - Compile and run code to check for C++ features
+#
+# This functions compiles a source file under the `cmake` folder
+# and adds the corresponding `HAVE_[FILENAME]` flag to the CMake
+# environment
+#
+# cxx_feature_check(<FLAG> [<VARIANT>])
+#
+# - Example
+#
+# include(CXXFeatureCheck)
+# cxx_feature_check(STD_REGEX)
+# Requires CMake 2.8.12+
+
+if(__cxx_feature_check)
+ return()
+endif()
+set(__cxx_feature_check INCLUDED)
+
+function(cxx_feature_check FILE)
+ string(TOLOWER ${FILE} FILE)
+ string(TOUPPER ${FILE} VAR)
+ string(TOUPPER "HAVE_${VAR}" FEATURE)
+ if (DEFINED HAVE_${VAR})
+ set(HAVE_${VAR} 1 PARENT_SCOPE)
+ add_definitions(-DHAVE_${VAR})
+ return()
+ endif()
+
+ if (NOT DEFINED COMPILE_${FEATURE})
+ message(STATUS "Performing Test ${FEATURE}")
+ if(CMAKE_CROSSCOMPILING)
+ try_compile(COMPILE_${FEATURE}
+ ${CMAKE_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/cmake/${FILE}.cpp
+ CMAKE_FLAGS ${BENCHMARK_CXX_LINKER_FLAGS}
+ LINK_LIBRARIES ${BENCHMARK_CXX_LIBRARIES})
+ if(COMPILE_${FEATURE})
+ message(WARNING
+ "If you see build failures due to cross compilation, try setting HAVE_${VAR} to 0")
+ set(RUN_${FEATURE} 0)
+ else()
+ set(RUN_${FEATURE} 1)
+ endif()
+ else()
+ message(STATUS "Performing Test ${FEATURE}")
+ try_run(RUN_${FEATURE} COMPILE_${FEATURE}
+ ${CMAKE_BINARY_DIR} ${CMAKE_CURRENT_SOURCE_DIR}/cmake/${FILE}.cpp
+ CMAKE_FLAGS ${BENCHMARK_CXX_LINKER_FLAGS}
+ LINK_LIBRARIES ${BENCHMARK_CXX_LIBRARIES})
+ endif()
+ endif()
+
+ if(RUN_${FEATURE} EQUAL 0)
+ message(STATUS "Performing Test ${FEATURE} -- success")
+ set(HAVE_${VAR} 1 PARENT_SCOPE)
+ add_definitions(-DHAVE_${VAR})
+ else()
+ if(NOT COMPILE_${FEATURE})
+ message(STATUS "Performing Test ${FEATURE} -- failed to compile")
+ else()
+ message(STATUS "Performing Test ${FEATURE} -- compiled but failed to run")
+ endif()
+ endif()
+endfunction()
diff --git a/cmake/Config.cmake.in b/cmake/Config.cmake.in
new file mode 100644
index 0000000..6e9256e
--- /dev/null
+++ b/cmake/Config.cmake.in
@@ -0,0 +1 @@
+include("${CMAKE_CURRENT_LIST_DIR}/@targets_export_name@.cmake")
diff --git a/cmake/GetGitVersion.cmake b/cmake/GetGitVersion.cmake
new file mode 100644
index 0000000..4f10f22
--- /dev/null
+++ b/cmake/GetGitVersion.cmake
@@ -0,0 +1,54 @@
+# - Returns a version string from Git tags
+#
+# This function inspects the annotated git tags for the project and returns a string
+# into a CMake variable
+#
+# get_git_version(<var>)
+#
+# - Example
+#
+# include(GetGitVersion)
+# get_git_version(GIT_VERSION)
+#
+# Requires CMake 2.8.11+
+find_package(Git)
+
+if(__get_git_version)
+ return()
+endif()
+set(__get_git_version INCLUDED)
+
+function(get_git_version var)
+ if(GIT_EXECUTABLE)
+ execute_process(COMMAND ${GIT_EXECUTABLE} describe --match "v[0-9]*.[0-9]*.[0-9]*" --abbrev=8
+ WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
+ RESULT_VARIABLE status
+ OUTPUT_VARIABLE GIT_VERSION
+ ERROR_QUIET)
+ if(${status})
+ set(GIT_VERSION "v0.0.0")
+ else()
+ string(STRIP ${GIT_VERSION} GIT_VERSION)
+ string(REGEX REPLACE "-[0-9]+-g" "-" GIT_VERSION ${GIT_VERSION})
+ endif()
+
+ # Work out if the repository is dirty
+ execute_process(COMMAND ${GIT_EXECUTABLE} update-index -q --refresh
+ WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
+ OUTPUT_QUIET
+ ERROR_QUIET)
+ execute_process(COMMAND ${GIT_EXECUTABLE} diff-index --name-only HEAD --
+ WORKING_DIRECTORY ${PROJECT_SOURCE_DIR}
+ OUTPUT_VARIABLE GIT_DIFF_INDEX
+ ERROR_QUIET)
+ string(COMPARE NOTEQUAL "${GIT_DIFF_INDEX}" "" GIT_DIRTY)
+ if (${GIT_DIRTY})
+ set(GIT_VERSION "${GIT_VERSION}-dirty")
+ endif()
+ else()
+ set(GIT_VERSION "v0.0.0")
+ endif()
+
+ message(STATUS "git Version: ${GIT_VERSION}")
+ set(${var} ${GIT_VERSION} PARENT_SCOPE)
+endfunction()
diff --git a/cmake/HandleGTest.cmake b/cmake/HandleGTest.cmake
new file mode 100644
index 0000000..b9c1443
--- /dev/null
+++ b/cmake/HandleGTest.cmake
@@ -0,0 +1,113 @@
+
+include(split_list)
+
+macro(build_external_gtest)
+ include(ExternalProject)
+ set(GTEST_FLAGS "")
+ if (BENCHMARK_USE_LIBCXX)
+ if ("${CMAKE_CXX_COMPILER_ID}" MATCHES "Clang")
+ list(APPEND GTEST_FLAGS -stdlib=libc++)
+ else()
+ message(WARNING "Unsupported compiler (${CMAKE_CXX_COMPILER}) when using libc++")
+ endif()
+ endif()
+ if (BENCHMARK_BUILD_32_BITS)
+ list(APPEND GTEST_FLAGS -m32)
+ endif()
+ if (NOT "${CMAKE_CXX_FLAGS}" STREQUAL "")
+ list(APPEND GTEST_FLAGS ${CMAKE_CXX_FLAGS})
+ endif()
+ string(TOUPPER "${CMAKE_BUILD_TYPE}" GTEST_BUILD_TYPE)
+ if ("${GTEST_BUILD_TYPE}" STREQUAL "COVERAGE")
+ set(GTEST_BUILD_TYPE "DEBUG")
+ endif()
+ # FIXME: Since 10/Feb/2017 the googletest trunk has had a bug where
+ # -Werror=unused-function fires during the build on OS X. This is a temporary
+ # workaround to keep our travis bots from failing. It should be removed
+ # once gtest is fixed.
+ if (NOT "${CMAKE_CXX_COMPILER_ID}" STREQUAL "MSVC")
+ list(APPEND GTEST_FLAGS "-Wno-unused-function")
+ endif()
+ split_list(GTEST_FLAGS)
+ set(EXCLUDE_FROM_ALL_OPT "")
+ set(EXCLUDE_FROM_ALL_VALUE "")
+ if (${CMAKE_VERSION} VERSION_GREATER "3.0.99")
+ set(EXCLUDE_FROM_ALL_OPT "EXCLUDE_FROM_ALL")
+ set(EXCLUDE_FROM_ALL_VALUE "ON")
+ endif()
+ ExternalProject_Add(googletest
+ ${EXCLUDE_FROM_ALL_OPT} ${EXCLUDE_FROM_ALL_VALUE}
+ GIT_REPOSITORY https://github.com/google/googletest.git
+ GIT_TAG master
+ PREFIX "${CMAKE_BINARY_DIR}/googletest"
+ INSTALL_DIR "${CMAKE_BINARY_DIR}/googletest"
+ CMAKE_CACHE_ARGS
+ -DCMAKE_BUILD_TYPE:STRING=${GTEST_BUILD_TYPE}
+ -DCMAKE_C_COMPILER:STRING=${CMAKE_C_COMPILER}
+ -DCMAKE_CXX_COMPILER:STRING=${CMAKE_CXX_COMPILER}
+ -DCMAKE_INSTALL_PREFIX:PATH=<INSTALL_DIR>
+ -DCMAKE_INSTALL_LIBDIR:PATH=<INSTALL_DIR>/lib
+ -DCMAKE_CXX_FLAGS:STRING=${GTEST_FLAGS}
+ -Dgtest_force_shared_crt:BOOL=ON
+ )
+
+ ExternalProject_Get_Property(googletest install_dir)
+ set(GTEST_INCLUDE_DIRS ${install_dir}/include)
+ file(MAKE_DIRECTORY ${GTEST_INCLUDE_DIRS})
+
+ set(LIB_SUFFIX "${CMAKE_STATIC_LIBRARY_SUFFIX}")
+ set(LIB_PREFIX "${CMAKE_STATIC_LIBRARY_PREFIX}")
+ if("${GTEST_BUILD_TYPE}" STREQUAL "DEBUG")
+ set(LIB_SUFFIX "d${CMAKE_STATIC_LIBRARY_SUFFIX}")
+ endif()
+
+ # Use gmock_main instead of gtest_main because it initializes gtest as well.
+ # Note: The libraries are listed in reverse order of their dependancies.
+ foreach(LIB gtest gmock gmock_main)
+ add_library(${LIB} UNKNOWN IMPORTED)
+ set_target_properties(${LIB} PROPERTIES
+ IMPORTED_LOCATION ${install_dir}/lib/${LIB_PREFIX}${LIB}${LIB_SUFFIX}
+ INTERFACE_INCLUDE_DIRECTORIES ${GTEST_INCLUDE_DIRS}
+ INTERFACE_LINK_LIBRARIES "${GTEST_BOTH_LIBRARIES}"
+ )
+ add_dependencies(${LIB} googletest)
+ list(APPEND GTEST_BOTH_LIBRARIES ${LIB})
+ endforeach()
+endmacro(build_external_gtest)
+
+if (BENCHMARK_ENABLE_GTEST_TESTS)
+ if (IS_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}/googletest)
+ set(GTEST_ROOT "${CMAKE_CURRENT_SOURCE_DIR}/googletest")
+ set(INSTALL_GTEST OFF CACHE INTERNAL "")
+ set(INSTALL_GMOCK OFF CACHE INTERNAL "")
+ add_subdirectory(${CMAKE_CURRENT_SOURCE_DIR}/googletest)
+ set(GTEST_BOTH_LIBRARIES gtest gmock gmock_main)
+ foreach(HEADER test mock)
+ # CMake 2.8 and older don't respect INTERFACE_INCLUDE_DIRECTORIES, so we
+ # have to add the paths ourselves.
+ set(HFILE g${HEADER}/g${HEADER}.h)
+ set(HPATH ${GTEST_ROOT}/google${HEADER}/include)
+ find_path(HEADER_PATH_${HEADER} ${HFILE}
+ NO_DEFAULT_PATHS
+ HINTS ${HPATH}
+ )
+ if (NOT HEADER_PATH_${HEADER})
+ message(FATAL_ERROR "Failed to find header ${HFILE} in ${HPATH}")
+ endif()
+ list(APPEND GTEST_INCLUDE_DIRS ${HEADER_PATH_${HEADER}})
+ endforeach()
+ elseif(BENCHMARK_DOWNLOAD_DEPENDENCIES)
+ build_external_gtest()
+ else()
+ find_package(GTest REQUIRED)
+ find_path(GMOCK_INCLUDE_DIRS gmock/gmock.h
+ HINTS ${GTEST_INCLUDE_DIRS})
+ if (NOT GMOCK_INCLUDE_DIRS)
+ message(FATAL_ERROR "Failed to find header gmock/gmock.h with hint ${GTEST_INCLUDE_DIRS}")
+ endif()
+ set(GTEST_INCLUDE_DIRS ${GTEST_INCLUDE_DIRS} ${GMOCK_INCLUDE_DIRS})
+ # FIXME: We don't currently require the gmock library to build the tests,
+ # and it's likely we won't find it, so we don't try. As long as we've
+ # found the gmock/gmock.h header and gtest_main that should be good enough.
+ endif()
+endif()
diff --git a/cmake/Modules/FindLLVMAr.cmake b/cmake/Modules/FindLLVMAr.cmake
new file mode 100644
index 0000000..2346981
--- /dev/null
+++ b/cmake/Modules/FindLLVMAr.cmake
@@ -0,0 +1,16 @@
+include(FeatureSummary)
+
+find_program(LLVMAR_EXECUTABLE
+ NAMES llvm-ar
+ DOC "The llvm-ar executable"
+ )
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(LLVMAr
+ DEFAULT_MSG
+ LLVMAR_EXECUTABLE)
+
+SET_PACKAGE_PROPERTIES(LLVMAr PROPERTIES
+ URL https://llvm.org/docs/CommandGuide/llvm-ar.html
+ DESCRIPTION "create, modify, and extract from archives"
+)
diff --git a/cmake/Modules/FindLLVMNm.cmake b/cmake/Modules/FindLLVMNm.cmake
new file mode 100644
index 0000000..e56430a
--- /dev/null
+++ b/cmake/Modules/FindLLVMNm.cmake
@@ -0,0 +1,16 @@
+include(FeatureSummary)
+
+find_program(LLVMNM_EXECUTABLE
+ NAMES llvm-nm
+ DOC "The llvm-nm executable"
+ )
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(LLVMNm
+ DEFAULT_MSG
+ LLVMNM_EXECUTABLE)
+
+SET_PACKAGE_PROPERTIES(LLVMNm PROPERTIES
+ URL https://llvm.org/docs/CommandGuide/llvm-nm.html
+ DESCRIPTION "list LLVM bitcode and object file’s symbol table"
+)
diff --git a/cmake/Modules/FindLLVMRanLib.cmake b/cmake/Modules/FindLLVMRanLib.cmake
new file mode 100644
index 0000000..7b53e1a
--- /dev/null
+++ b/cmake/Modules/FindLLVMRanLib.cmake
@@ -0,0 +1,15 @@
+include(FeatureSummary)
+
+find_program(LLVMRANLIB_EXECUTABLE
+ NAMES llvm-ranlib
+ DOC "The llvm-ranlib executable"
+ )
+
+include(FindPackageHandleStandardArgs)
+find_package_handle_standard_args(LLVMRanLib
+ DEFAULT_MSG
+ LLVMRANLIB_EXECUTABLE)
+
+SET_PACKAGE_PROPERTIES(LLVMRanLib PROPERTIES
+ DESCRIPTION "generate index for LLVM archive"
+)
diff --git a/cmake/benchmark.pc.in b/cmake/benchmark.pc.in
new file mode 100644
index 0000000..1e84bff
--- /dev/null
+++ b/cmake/benchmark.pc.in
@@ -0,0 +1,11 @@
+prefix=@CMAKE_INSTALL_PREFIX@
+exec_prefix=${prefix}
+libdir=${prefix}/lib
+includedir=${prefix}/include
+
+Name: @PROJECT_NAME@
+Description: Google microbenchmark framework
+Version: @VERSION@
+
+Libs: -L${libdir} -lbenchmark
+Cflags: -I${includedir}
diff --git a/cmake/gnu_posix_regex.cpp b/cmake/gnu_posix_regex.cpp
new file mode 100644
index 0000000..b5b91cd
--- /dev/null
+++ b/cmake/gnu_posix_regex.cpp
@@ -0,0 +1,12 @@
+#include <gnuregex.h>
+#include <string>
+int main() {
+ std::string str = "test0159";
+ regex_t re;
+ int ec = regcomp(&re, "^[a-z]+[0-9]+$", REG_EXTENDED | REG_NOSUB);
+ if (ec != 0) {
+ return ec;
+ }
+ return regexec(&re, str.c_str(), 0, nullptr, 0) ? -1 : 0;
+}
+
diff --git a/cmake/llvm-toolchain.cmake b/cmake/llvm-toolchain.cmake
new file mode 100644
index 0000000..fc119e5
--- /dev/null
+++ b/cmake/llvm-toolchain.cmake
@@ -0,0 +1,8 @@
+find_package(LLVMAr REQUIRED)
+set(CMAKE_AR "${LLVMAR_EXECUTABLE}" CACHE FILEPATH "" FORCE)
+
+find_package(LLVMNm REQUIRED)
+set(CMAKE_NM "${LLVMNM_EXECUTABLE}" CACHE FILEPATH "" FORCE)
+
+find_package(LLVMRanLib REQUIRED)
+set(CMAKE_RANLIB "${LLVMRANLIB_EXECUTABLE}" CACHE FILEPATH "" FORCE)
diff --git a/cmake/posix_regex.cpp b/cmake/posix_regex.cpp
new file mode 100644
index 0000000..466dc62
--- /dev/null
+++ b/cmake/posix_regex.cpp
@@ -0,0 +1,14 @@
+#include <regex.h>
+#include <string>
+int main() {
+ std::string str = "test0159";
+ regex_t re;
+ int ec = regcomp(&re, "^[a-z]+[0-9]+$", REG_EXTENDED | REG_NOSUB);
+ if (ec != 0) {
+ return ec;
+ }
+ int ret = regexec(&re, str.c_str(), 0, nullptr, 0) ? -1 : 0;
+ regfree(&re);
+ return ret;
+}
+
diff --git a/cmake/split_list.cmake b/cmake/split_list.cmake
new file mode 100644
index 0000000..67aed3f
--- /dev/null
+++ b/cmake/split_list.cmake
@@ -0,0 +1,3 @@
+macro(split_list listname)
+ string(REPLACE ";" " " ${listname} "${${listname}}")
+endmacro()
diff --git a/cmake/std_regex.cpp b/cmake/std_regex.cpp
new file mode 100644
index 0000000..696f2a2
--- /dev/null
+++ b/cmake/std_regex.cpp
@@ -0,0 +1,10 @@
+#include <regex>
+#include <string>
+int main() {
+ const std::string str = "test0159";
+ std::regex re;
+ re = std::regex("^[a-z]+[0-9]+$",
+ std::regex_constants::extended | std::regex_constants::nosubs);
+ return std::regex_search(str, re) ? 0 : -1;
+}
+
diff --git a/cmake/steady_clock.cpp b/cmake/steady_clock.cpp
new file mode 100644
index 0000000..66d50d1
--- /dev/null
+++ b/cmake/steady_clock.cpp
@@ -0,0 +1,7 @@
+#include <chrono>
+
+int main() {
+ typedef std::chrono::steady_clock Clock;
+ Clock::time_point tp = Clock::now();
+ ((void)tp);
+}
diff --git a/cmake/thread_safety_attributes.cpp b/cmake/thread_safety_attributes.cpp
new file mode 100644
index 0000000..46161ba
--- /dev/null
+++ b/cmake/thread_safety_attributes.cpp
@@ -0,0 +1,4 @@
+#define HAVE_THREAD_SAFETY_ATTRIBUTES
+#include "../src/mutex.h"
+
+int main() {}