#if (SIZEOF_INT == 4)
# ifndef int32
# define int32 int
-# define INT32_MIN INT_MIN
-# define INT32_MAX INT_MAX
+# ifndef INT32_MIN
+# define INT32_MIN INT_MIN
+# endif
+# ifndef INT32_MAX
+# define INT32_MAX INT_MAX
+# endif
# endif
# ifndef u_int32
# define u_int32 unsigned int
-# define U_INT32_MAX UINT_MAX
+# ifndef U_INT32_MAX
+# define U_INT32_MAX UINT_MAX
+# endif
# endif
#else /* not sizeof(int) == 4 */
# if (SIZEOF_LONG == 4)
# ifndef int32
# define int32 long
-# define INT32_MIN LONG_MIN
-# define INT32_MAX LONG_MAX
+# ifndef INT32_MIN
+# define INT32_MIN LONG_MIN
+# endif
+# ifndef INT32_MAX
+# define INT32_MAX LONG_MAX
+# endif
# endif
# ifndef u_int32
# define u_int32 unsigned long
-# define U_INT32_MAX ULONG_MAX
+# ifndef U_INT32_MAX
+# define U_INT32_MAX ULONG_MAX
+# endif
# endif
# else /* not sizeof(long) == 4 */
# include "Bletch: what's 32 bits on this machine?"