Throwing constructors and member destructors

[Boris-Barboris]

https://run.dlang.io/is/LdylJX

Notice no "B destructor" line in stdout.

Just got bitten by the assumption that my Buffer struct that 
transactionally aquires multiple external resources in 
constructor will rollback via member destructors that were 
successfully completed before the throw.

Can I get a clarification about current semantics? Should I 
essentially never throw in constructors if I want to rely on 
scope-based RAII?

And before we start a 10-page argument about the ideology of 
constructors, I would mostly just like to hear that this is 
documented somewhere, because I have certanly missed it.