I think the word static was misused in nkurz's post. static variables are always initialized, at least to 0. Initializing a stack variable shouldn't harm performance.

Correct, I was trying to describe initializing a stack variable to a constant array, and shouldn't have used the word static. In retrospect, I think the cost of this is probably just the same as zeroing it, since behind the scenes it has to be copied from a constant? But the rejection wasn't due to the performance harm, but was based on a philosophy that one shouldn't change "provably" correct just to make it more compliant.

I may be using incorrect terminology, or at least I think you are presuming a more object oriented interpretation. I don't recall the exact circumstance, but it was a case where one would normally call calloc() rather than malloc() once for a buffer. This proposal to switch to calloc() was rejected due to expense of calling bzero(). I think I proposed making it a array with an initializer rather than a pointer, taking a couple KB size penalty in return for quieting a warning and removing some code smell.

The code wasn't merely copying an uninitialized variable, it was branching on the random data that happened to be in the data returned by malloc(). This confused Valgrind, but was thought to be safe due to some later check. To me this was fragile code and unsafe practice. To the decision makers, it was a good way to save a couple cycles and a few bytes. The culture (at least at the time) felt that efficiency trumped clarity and maintainability. This is a blessing and a curse.