diff --git a/include/nuttx/lib/math32.h b/include/nuttx/lib/math32.h
index acfd09749f64b..07b955b4d0dbe 100644
--- a/include/nuttx/lib/math32.h
+++ b/include/nuttx/lib/math32.h
@@ -260,12 +260,12 @@ extern "C"
       })
 
 #  define div_const(n, base) \
-    ((sizeof(n) == sizeof(uint64_t)) ? div64_const(n, base) : ((n) / (base)))
+    ((sizeof(typeof(n)) == sizeof(uint64_t)) ? div64_const(n, base) : ((n) / (base)))
 #  define div_const_roundup(n, base) \
-    ((sizeof(n) == sizeof(uint64_t)) ? div64_const((n) + (base) - 1, base) : \
+    ((sizeof(typeof(n)) == sizeof(uint64_t)) ? div64_const((n) + (base) - 1, base) : \
      (((n) + (base) - 1) / (base)))
 #  define div_const_roundnearest(n, base) \
-    ((sizeof(n) == sizeof(uint64_t)) ? div64_const((n) + ((base) / 2), base) : \
+    ((sizeof(typeof(n)) == sizeof(uint64_t)) ? div64_const((n) + ((base) / 2), base) : \
      (((n) + ((base) / 2)) / (base)))
 #else
 #  define div_const(n, base) ((n) / (base))