diff --git a/src/pulsecore/mutex-posix.c b/src/pulsecore/mutex-posix.c
index d0156dbf1..08baa3860 100644
--- a/src/pulsecore/mutex-posix.c
+++ b/src/pulsecore/mutex-posix.c
@@ -25,6 +25,8 @@
 
 #include <assert.h>
 #include <pthread.h>
+
+#define AO_REQUIRE_CAS
 #include <atomic_ops.h>
 
 #include <pulse/xmalloc.h>
diff --git a/src/pulsecore/refcnt.h b/src/pulsecore/refcnt.h
index fade9aa47..ff0a99238 100644
--- a/src/pulsecore/refcnt.h
+++ b/src/pulsecore/refcnt.h
@@ -22,6 +22,7 @@
   USA.
 ***/
 
+#define AO_REQUIRE_CAS
 #include <atomic_ops.h>
 
 #define PA_REFCNT_DECLARE volatile AO_t _ref
diff --git a/src/pulsecore/thread-posix.c b/src/pulsecore/thread-posix.c
index 15ade2909..54f21b75a 100644
--- a/src/pulsecore/thread-posix.c
+++ b/src/pulsecore/thread-posix.c
@@ -25,6 +25,8 @@
 
 #include <assert.h>
 #include <pthread.h>
+
+#define AO_REQUIRE_CAS
 #include <atomic_ops.h>
 
 #include <pulse/xmalloc.h>