There's a crash caused by accessing an array element past the last one in base58.h, in the SecretToASecret function.

Code:

vch.insert(vch.end(), &vchSecret[0], &vchSecret[vchSecret.size()]);

vchSecret.size() is one past the last element, so it crashes here.

Since vchSecret is just a vector anyway, we can use this safer alternative:

Code:

vch.insert(vch.end(), vchSecret.begin(), vchSecret.end());

So the issue I posted above is a simple typo on sipa's commit. Instead of puddinpop's proposed change:

Code:

vch.insert(vch.end(), vchSecret.begin(), vchSecret.end());

You changed the code to

Code:

vch.insert(vch.end(), vch.begin(), vch.end());

The secret "vchSecret" was never being used.