mirror of
				https://github.com/PurpleI2P/i2pd.git
				synced 2025-11-04 08:30:46 +00:00 
			
		
		
		
	Fix CheckAtomic.cmake
This commit is contained in:
		
							parent
							
								
									6376328c98
								
							
						
					
					
						commit
						54b7d4ef32
					
				
					 1 changed files with 25 additions and 19 deletions
				
			
		| 
						 | 
				
			
			@ -1,18 +1,23 @@
 | 
			
		|||
# atomic builtins are required for threading support.
 | 
			
		||||
 | 
			
		||||
INCLUDE(CheckCXXSourceCompiles)
 | 
			
		||||
INCLUDE(CheckLibraryExists)
 | 
			
		||||
 | 
			
		||||
# Sometimes linking against libatomic is required for atomic ops, if
 | 
			
		||||
# the platform doesn't support lock-free atomics.
 | 
			
		||||
 | 
			
		||||
function(check_working_cxx_atomics varname)
 | 
			
		||||
  set(OLD_CMAKE_REQUIRED_FLAGS ${CMAKE_REQUIRED_FLAGS})
 | 
			
		||||
  set(CMAKE_REQUIRED_FLAGS "-std=c++11")
 | 
			
		||||
  set(CMAKE_REQUIRED_FLAGS "${CMAKE_REQUIRED_FLAGS} -std=c++11")
 | 
			
		||||
  CHECK_CXX_SOURCE_COMPILES("
 | 
			
		||||
#include <atomic>
 | 
			
		||||
std::atomic<int> x;
 | 
			
		||||
std::atomic<short> y;
 | 
			
		||||
std::atomic<char> z;
 | 
			
		||||
int main() {
 | 
			
		||||
  return x;
 | 
			
		||||
  ++z;
 | 
			
		||||
  ++y;
 | 
			
		||||
  return ++x;
 | 
			
		||||
}
 | 
			
		||||
" ${varname})
 | 
			
		||||
  set(CMAKE_REQUIRED_FLAGS ${OLD_CMAKE_REQUIRED_FLAGS})
 | 
			
		||||
| 
						 | 
				
			
			@ -27,6 +32,7 @@ function(check_working_cxx_atomics64 varname)
 | 
			
		|||
std::atomic<uint64_t> x (0);
 | 
			
		||||
int main() {
 | 
			
		||||
  uint64_t i = x.load(std::memory_order_relaxed);
 | 
			
		||||
  (void)i;
 | 
			
		||||
  return 0;
 | 
			
		||||
}
 | 
			
		||||
" ${varname})
 | 
			
		||||
| 
						 | 
				
			
			@ -34,15 +40,16 @@ int main() {
 | 
			
		|||
endfunction(check_working_cxx_atomics64)
 | 
			
		||||
 | 
			
		||||
 | 
			
		||||
# This isn't necessary on MSVC, so avoid command-line switch annoyance
 | 
			
		||||
# by only running on GCC-like hosts.
 | 
			
		||||
if (LLVM_COMPILER_IS_GCC_COMPATIBLE)
 | 
			
		||||
# Check for (non-64-bit) atomic operations.
 | 
			
		||||
if(MSVC)
 | 
			
		||||
  set(HAVE_CXX_ATOMICS_WITHOUT_LIB True)
 | 
			
		||||
else()
 | 
			
		||||
  # First check if atomics work without the library.
 | 
			
		||||
  check_working_cxx_atomics(HAVE_CXX_ATOMICS_WITHOUT_LIB)
 | 
			
		||||
  # If not, check if the library exists, and atomics work with it.
 | 
			
		||||
  if(NOT HAVE_CXX_ATOMICS_WITHOUT_LIB)
 | 
			
		||||
    check_library_exists(atomic __atomic_fetch_add_4 "" HAVE_LIBATOMIC)
 | 
			
		||||
    if( HAVE_LIBATOMIC )
 | 
			
		||||
    if(HAVE_LIBATOMIC)
 | 
			
		||||
      list(APPEND CMAKE_REQUIRED_LIBRARIES "atomic")
 | 
			
		||||
      check_working_cxx_atomics(HAVE_CXX_ATOMICS_WITH_LIB)
 | 
			
		||||
      if (NOT HAVE_CXX_ATOMICS_WITH_LIB)
 | 
			
		||||
| 
						 | 
				
			
			@ -58,20 +65,20 @@ endif()
 | 
			
		|||
if(MSVC)
 | 
			
		||||
  set(HAVE_CXX_ATOMICS64_WITHOUT_LIB True)
 | 
			
		||||
else()
 | 
			
		||||
  # First check if atomics work without the library.
 | 
			
		||||
  check_working_cxx_atomics64(HAVE_CXX_ATOMICS64_WITHOUT_LIB)
 | 
			
		||||
endif()
 | 
			
		||||
 | 
			
		||||
# If not, check if the library exists, and atomics work with it.
 | 
			
		||||
if(NOT HAVE_CXX_ATOMICS64_WITHOUT_LIB)
 | 
			
		||||
  check_library_exists(atomic __atomic_load_8 "" HAVE_CXX_LIBATOMICS64)
 | 
			
		||||
  if(HAVE_CXX_LIBATOMICS64)
 | 
			
		||||
    list(APPEND CMAKE_REQUIRED_LIBRARIES "atomic")
 | 
			
		||||
    check_working_cxx_atomics64(HAVE_CXX_ATOMICS64_WITH_LIB)
 | 
			
		||||
    if (NOT HAVE_CXX_ATOMICS64_WITH_LIB)
 | 
			
		||||
      message(FATAL_ERROR "Host compiler must support std::atomic!")
 | 
			
		||||
  # If not, check if the library exists, and atomics work with it.
 | 
			
		||||
  if(NOT HAVE_CXX_ATOMICS64_WITHOUT_LIB)
 | 
			
		||||
    check_library_exists(atomic __atomic_load_8 "" HAVE_CXX_LIBATOMICS64)
 | 
			
		||||
    if(HAVE_CXX_LIBATOMICS64)
 | 
			
		||||
      list(APPEND CMAKE_REQUIRED_LIBRARIES "atomic")
 | 
			
		||||
      check_working_cxx_atomics64(HAVE_CXX_ATOMICS64_WITH_LIB)
 | 
			
		||||
      if (NOT HAVE_CXX_ATOMICS64_WITH_LIB)
 | 
			
		||||
        message(FATAL_ERROR "Host compiler must support 64-bit std::atomic!")
 | 
			
		||||
      endif()
 | 
			
		||||
    else()
 | 
			
		||||
      message(FATAL_ERROR "Host compiler appears to require libatomic for 64-bit operations, but cannot find it.")
 | 
			
		||||
    endif()
 | 
			
		||||
  else()
 | 
			
		||||
    message(FATAL_ERROR "Host compiler appears to require libatomic, but cannot find it.")
 | 
			
		||||
  endif()
 | 
			
		||||
endif()
 | 
			
		||||
 | 
			
		||||
| 
						 | 
				
			
			@ -80,7 +87,6 @@ endif()
 | 
			
		|||
## assumes C++11 <atomic> works.
 | 
			
		||||
CHECK_CXX_SOURCE_COMPILES("
 | 
			
		||||
#ifdef _MSC_VER
 | 
			
		||||
#include <Intrin.h> /* Workaround for PR19898. */
 | 
			
		||||
#include <windows.h>
 | 
			
		||||
#endif
 | 
			
		||||
int main() {
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
		Loading…
	
	Add table
		Add a link
		
	
		Reference in a new issue