protect find_msb from passing 0

NilFoundation · Sep 25, 2024 · 2d082c1 · 2d082c1
1 parent 82a0813
commit 2d082c1
Showing 1 changed file with 2 additions and 0 deletions.
diff --git a/crypto3/libs/multiprecision/include/nil/crypto3/multiprecision/cpp_int_modular/misc.hpp b/crypto3/libs/multiprecision/include/nil/crypto3/multiprecision/cpp_int_modular/misc.hpp
@@ -148,6 +148,8 @@ namespace boost {
                             return i * cpp_int_modular_backend<Bits>::limb_bits + 
                                 boost::multiprecision::detail::find_msb(a.limbs()[i]);
                     } 
+                    if (a.limbs()[0] == 0) // TODO here should assert/throw
+                        return 1024; // Some big number to indicate that there is no bit 1
                     return boost::multiprecision::detail::find_msb(a.limbs()[0]);
                 }