1 include(CheckCXXSourceCompiles)
2 include(CheckCXXSourceRuns)
3 include(CheckFunctionExists)
4 include(CheckIncludeFile)
5 include(CheckSymbolExists)
7 include(CheckCXXCompilerFlag)
9 CHECK_INCLUDE_FILE_CXX(malloc.h FOLLY_HAVE_MALLOC_H)
10 CHECK_INCLUDE_FILE_CXX(bits/functexcept.h FOLLY_HAVE_BITS_FUNCTEXCEPT_H)
11 CHECK_INCLUDE_FILE_CXX(bits/c++config.h FOLLY_HAVE_BITS_CXXCONFIG_H)
12 CHECK_INCLUDE_FILE_CXX(features.h FOLLY_HAVE_FEATURES_H)
13 CHECK_INCLUDE_FILE_CXX(linux/membarrier.h FOLLY_HAVE_LINUX_MEMBARRIER_H)
14 CHECK_INCLUDE_FILE_CXX(jemalloc/jemalloc.h FOLLY_USE_JEMALLOC)
16 if(NOT CMAKE_SYSTEM_NAME STREQUAL "Windows")
17 # clang only rejects unknown warning flags if -Werror=unknown-warning-option
19 CHECK_CXX_COMPILER_FLAG(
20 -Werror=unknown-warning-option
21 COMPILER_HAS_UNKNOWN_WARNING_OPTION)
22 if (COMPILER_HAS_UNKNOWN_WARNING_OPTION)
23 list(APPEND CMAKE_REQUIRED_FLAGS -Werror=unknown-warning-option)
26 CHECK_CXX_COMPILER_FLAG(-Wshadow-local COMPILER_HAS_W_SHADOW_LOCAL)
27 CHECK_CXX_COMPILER_FLAG(
28 -Wshadow-compatible-local
29 COMPILER_HAS_W_SHADOW_COMPATIBLE_LOCAL)
30 if (COMPILER_HAS_W_SHADOW_LOCAL AND COMPILER_HAS_W_SHADOW_COMPATIBLE_LOCAL)
31 set(FOLLY_HAVE_SHADOW_LOCAL_WARNINGS ON)
35 check_symbol_exists(pthread_atfork pthread.h FOLLY_HAVE_PTHREAD_ATFORK)
37 # Unfortunately check_symbol_exists() does not work for memrchr():
38 # it fails complaining that there are multiple overloaded versions of memrchr()
39 check_function_exists(memrchr FOLLY_HAVE_MEMRCHR)
40 check_symbol_exists(preadv sys/uio.h FOLLY_HAVE_PREADV)
41 check_symbol_exists(pwritev sys/uio.h FOLLY_HAVE_PWRITEV)
42 check_symbol_exists(clock_gettime time.h FOLLY_HAVE_CLOCK_GETTIME)
44 check_function_exists(
45 cplus_demangle_v3_callback
46 FOLLY_HAVE_CPLUS_DEMANGLE_V3_CALLBACK
48 check_function_exists(malloc_usable_size FOLLY_HAVE_MALLOC_USABLE_SIZE)
50 check_cxx_source_compiles("
51 #pragma GCC diagnostic error \"-Wattributes\"
52 extern \"C\" void (*test_ifunc(void))() { return 0; }
53 void func() __attribute__((ifunc(\"test_ifunc\")));
54 int main() { return 0; }"
57 check_cxx_source_compiles("
58 #include <type_traits>
59 const bool val = std::is_trivially_copyable<bool>::value;
60 int main() { return 0; }"
61 FOLLY_HAVE_STD__IS_TRIVIALLY_COPYABLE
63 check_cxx_source_runs("
64 int main(int, char**) {
66 unsigned long *ptr = (unsigned long *)(buf + 1);
68 return (*ptr & 0xff) == 0xef ? 0 : 1;
70 FOLLY_HAVE_UNALIGNED_ACCESS
72 check_cxx_source_compiles("
73 int main(int argc, char** argv) {
80 check_cxx_source_compiles("
81 extern \"C\" void configure_link_extern_weak_test() __attribute__((weak));
82 int main(int argc, char** argv) {
83 return configure_link_extern_weak_test == nullptr;
85 FOLLY_HAVE_WEAK_SYMBOLS
87 check_cxx_source_runs("
90 void *h = dlopen(\"linux-vdso.so.1\", RTLD_LAZY | RTLD_LOCAL | RTLD_NOLOAD);
100 check_type_size(__int128 INT128_SIZE LANGUAGE CXX)
101 if (NOT INT128_SIZE STREQUAL "")
102 set(FOLLY_HAVE_INT128_T ON)
103 check_cxx_source_compiles("
104 #include <type_traits>
106 ::std::is_same<::std::make_signed<unsigned __int128>::type,
108 \"signed form of \`unsigned __uint128\` must be \`__int128\`.\");
109 int main() { return 0; }"
112 if (HAVE_INT128_TRAITS)
113 set(FOLLY_SUPPLY_MISSING_INT128_TRAITS OFF)
115 set(FOLLY_SUPPLY_MISSING_INT128_TRAITS ON)
119 check_cxx_source_runs("
122 int main(int argc, char** argv) {
123 return wcstol(L\"01\", nullptr, 10) == 1 ? 0 : 1;
125 FOLLY_HAVE_WCHAR_SUPPORT
128 check_cxx_source_compiles("
129 #include <ext/random>
130 int main(int argc, char** argv) {
131 __gnu_cxx::sfmt19937 rng;
134 FOLLY_HAVE_EXTRANDOM_SFMT19937
137 check_cxx_source_compiles("
138 #include <type_traits>
146 check_cxx_source_runs("
149 int main(int argc, char** argv) {
152 int ret = strerror_r(ENOMEM, buf, sizeof(buf));
155 FOLLY_HAVE_XSI_STRERROR_R
158 check_cxx_source_runs("
162 int call_vsnprintf(const char* fmt, ...) {
166 int result = vsnprintf(buf, sizeof(buf), fmt, ap);
171 int main(int argc, char** argv) {
172 return call_vsnprintf(\"%\", 1) < 0 ? 0 : 1;
174 HAVE_VSNPRINTF_ERRORS
177 if (FOLLY_HAVE_LIBGFLAGS)
178 # Older releases of gflags used the namespace "gflags"; newer releases
179 # use "google" but also make symbols available in the deprecated "gflags"
180 # namespace too. The folly code internally uses "gflags" unless we tell it
182 check_cxx_source_compiles("
183 #include <gflags/gflags.h>
189 GFLAGS_NAMESPACE_IS_GFLAGS
191 if (GFLAGS_NAMESPACE_IS_GFLAGS)
192 set(FOLLY_UNUSUAL_GFLAGS_NAMESPACE OFF)
193 set(FOLLY_GFLAGS_NAMESPACE gflags)
195 set(FOLLY_UNUSUAL_GFLAGS_NAMESPACE ON)
196 set(FOLLY_GFLAGS_NAMESPACE google)
200 set(FOLLY_USE_SYMBOLIZER OFF)
201 CHECK_INCLUDE_FILE_CXX(elf.h FOLLY_HAVE_ELF_H)
202 find_library(UNWIND_LIBRARIES NAMES unwind)
203 if (UNWIND_LIBRARIES)
204 list(APPEND FOLLY_LINK_LIBRARIES ${UNWIND_LIBRARIES})
205 list(APPEND CMAKE_REQUIRED_LIBRARIES ${UNWIND_LIBRARIES})
207 check_function_exists(backtrace FOLLY_HAVE_BACKTRACE)
208 if (FOLLY_HAVE_ELF_H AND FOLLY_HAVE_BACKTRACE AND LIBDWARF_FOUND)
209 set(FOLLY_USE_SYMBOLIZER ON)
211 message(STATUS "Setting FOLLY_USE_SYMBOLIZER: ${FOLLY_USE_SYMBOLIZER}")