That's a lot of ifdefs, sure. But at least Vim doesn't have it's own malloc which never frees and can be dynamically replaced at runtime and occasionally logs sensitive information.

As long as you don't statically link you can easily replace malloc (LD_PRELOAD). Many debug libraries do. Why is this so special in openssl? (I don't know if there is some special reason, though openssl is a weird one to begin with)