diff --git a/src/util.c b/src/util.c
index 42c1a3c..e1dcc6d 100644
--- a/src/util.c
+++ b/src/util.c
@@ -422,7 +422,7 @@ void addparentstats(struct dir *d, int64_t size, int64_t asize, uint64_t mtime,
 #define wrap_oom(f) \
   void *ptr;\
   char buf[128];\
-  while((ptr = f) == NULL) {\
+  while((ptr = (f)) == NULL) {\
     close_nc();\
     (void) !write(2, oom_msg, sizeof(oom_msg));\
     (void) !read(0, buf, sizeof(buf));\