diff options
Diffstat (limited to 'cmake/modules')
-rw-r--r-- | cmake/modules/CheckAtomic.cmake | 18 |
1 files changed, 18 insertions, 0 deletions
diff --git a/cmake/modules/CheckAtomic.cmake b/cmake/modules/CheckAtomic.cmake new file mode 100644 index 0000000..27bbaba --- /dev/null +++ b/cmake/modules/CheckAtomic.cmake @@ -0,0 +1,18 @@ +# atomic builtins are required for threading support. + +INCLUDE(CheckCXXSourceCompiles) + +CHECK_CXX_SOURCE_COMPILES(" +int main() { + volatile unsigned long val = 1; + __sync_synchronize(); + __sync_val_compare_and_swap(&val, 1, 0); + __sync_add_and_fetch(&val, 1); + __sync_sub_and_fetch(&val, 1); + return 0; + } +" LLVM_MULTITHREADED) + +if( NOT LLVM_MULTITHREADED ) + message(STATUS "Warning: LLVM will be built thread-unsafe because atomic builtins are missing") +endif() |