In practice, all the code in distributions has built in environments with 64 bit time_t. Some end-user legacy code may not be, but it probably isn't much: most

In practice, all the code in distributions has built in environments with 64 bit time_t. Some end-user legacy code may not be, but it probably isn't much: most things just don't care about a field getting wider behind the scenes. The big pain, IMO, at this point is the big cutover where all libraries need to move to the new ABI. This still doesn't prove things as 2038-safe, but it at least means things reasonably can be 2038-safe on 32 bit if they choose... while today it's impossible for practical purposes.