Re: [boost] [mp_int] Incorrect comparison with native types

Subject: Re: [boost] [mp_int] Incorrect comparison with native types
From: Nathan Kitchen (nathan.kitchen_at_[hidden])
Date: 2009-01-11 00:04:08

Other operations with incorrect results:

(1)

mp_int<> a = "0x100000000";
a = -a;

cout << (a < -1) << endl;

This can be fixed by changing line 228 of
mp_math/mp_int/detail/integral_ops.hpp (in integral_ops_impl<...,
true>::less):

    if (lhs.size() > q)
-     return false;
+   return lhs.sign() == -1;

(2)

mp_int<> a = 13;
int b = -1;
cout << (a | b) << endl; // Should be -1, right?

Likewise for bitwise AND and XOR.

-- Nathan