To me, a broken abstraction is when the programmer writing in the high-level language needs to know low-level details or quirks of the implementation to get the high-level code to work correctly. I would call the techniques in this article compiler optimizations, not broken abstractions. Toward the end he says "Go breaks the simple abstraction of a stack that most C compilers assume" but I don't think of compilers as using abstractions. Barry Kelly's comment is good. - Bruce Lewis