I also do not agree with that. This is bad for so many reasons. First, to the compiler code, comments should be discarded as soon as possible (often in the lexer). To the programmers, comments should never execute anything (this is just intuitively expected). To any go source code reader (human or machine), comments are supposed to contain only human readable text, probably a context sensitive explanation of that particular section of code. To the separation of concerns, comments are comments and compiler directives are compiler directives. To each his own.

This is probably the only decision I disagree with the Go team to date.