diff --git a/lib_com/cnst.h b/lib_com/cnst.h
index 53032d5aeae9b266126968ab19d81ea76c8690e7..8faa2cb57dc76b84910430a3fda9a179e638c49c 100644
--- a/lib_com/cnst.h
+++ b/lib_com/cnst.h
@@ -134,7 +134,7 @@
 #define ONE_IN_Q29                      536870912
 #define ONE_IN_Q30                      1073741824
 #define ONE_IN_Q31                      0x7fffffff
-#define MINUS_ONE_IN_Q31                0x80000000
+#define MINUS_ONE_IN_Q31                (-2147483647 - 1)
 #define TWO_IN_Q29                      1073741824
 #define FOUR_IN_Q28                     1073741824