1# atomic builtins are required for threading support.
2
3INCLUDE(CheckCXXSourceCompiles)
4
5CHECK_CXX_SOURCE_COMPILES("
6int main() {
7        volatile unsigned long val = 1;
8        __sync_synchronize();
9        __sync_val_compare_and_swap(&val, 1, 0);
10        __sync_add_and_fetch(&val, 1);
11        __sync_sub_and_fetch(&val, 1);
12        return 0;
13      }
14" LLVM_MULTITHREADED)
15
16if( NOT LLVM_MULTITHREADED )
17  message(STATUS "Warning: LLVM will be built thread-unsafe because atomic builtins are missing")
18endif()
19