How much experience have you of languages that zero-initialize before the constructor is called?

I was a compiler engineer at Borland / Embarcadero on Delphi, a non-GC language with a zero-init approach. Java zero-initializes. C# zero-initializes. In fact, I struggle to think of a modern language that doesn't zero-init or prevents access to uninitialized fields by definite assignment analysis.

Overhead in C++ is a different story. C++ is not low overhead enough, to me, to justify the claims made for it. For example, I like static data structures, especially in C. But in C++ they are unidiomatic. How do you statically initialize (in the rdata / rodata segment) an object graph (even as simple as a tree) with zero-copying at runtime?

Or how about copy constructors that may throw exceptions. That leads to inefficient APIs for things like std::stack::pop(). Guarding against exceptions in generic code has implicit overhead when the type system is as user-mutable as C++.