diff --git a/libavutil/tx_priv.h b/libavutil/tx_priv.h
index 72f336eea7..d5ff8e1421 100644
--- a/libavutil/tx_priv.h
+++ b/libavutil/tx_priv.h
@@ -102,6 +102,12 @@ typedef void TXComplex;
 
 #define FOLD(a, b) ((a) + (b))
 
+#define BF(x, y, a, b)  \
+    do {                \
+        x = (a) - (b);  \
+        y = (a) + (b);  \
+    } while (0)
+
 #elif defined(TX_INT32)
 
 /* Properly rounds the result */
@@ -132,14 +138,14 @@ typedef void TXComplex;
 
 #define FOLD(x, y) ((int32_t)((x) + (unsigned)(y) + 32) >> 6)
 
-#endif /* TX_INT32 */
-
 #define BF(x, y, a, b)  \
     do {                \
-        x = (a) - (b);  \
-        y = (a) + (b);  \
+        x = (a) - (unsigned)(b);  \
+        y = (a) + (unsigned)(b);  \
     } while (0)
 
+#endif /* TX_INT32 */
+
 #define CMUL3(c, a, b) CMUL((c).re, (c).im, (a).re, (a).im, (b).re, (b).im)
 
 /* Codelet flags, used to pick codelets. Must be a superset of enum AVTXFlags,