... > What I remember is that since perf_sample_data is fairly large, > unconditionally initializing the whole thing is *slow* (and > -fauto-var-init=zero will hurt here).
That will hurt everywhere. I can also imagine it hiding bugs and making people shrink on-stack arrays to the point where they either overrun or cause an unexpected error or string truncation. Initialising to zero is a bad choice if the aim is to avoid leaking stack. David - Registered Address Lakeside, Bramley Road, Mount Farm, Milton Keynes, MK1 1PT, UK Registration No: 1397386 (Wales)