Fix libeio compilation on clang

include/tarantool_eio.h

@@ -28,6 +28,9 @@
  * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  * SUCH DAMAGE.
  */
+
+#include <stdio.h>
+#include <fcntl.h> /* Definition of AT_* constants */
 #include <sys/types.h>
 #include <sys/stat.h>
 #include <sys/time.h>

src/CMakeLists.txt

@@ -49,6 +49,8 @@ target_link_libraries(ev ${ev_libs})
 #
 # libeio library
 #
+set_source_files_properties(tarantool_eio.c
+    PROPERTIES COMPILE_FLAGS "-Wno-unused-value -Wno-dangling-else")
 add_library(eio tarantool_eio.c)
 
 #