The author is a total idiot. The C++ language is totally unsafe, so when you call third-party code, literally anything can happen. Just because there might be

The author is a total idiot. The C++ language is totally unsafe, so when you call third-party code, literally anything can happen. Just because there might be a convention for "const" methods to be thread-safe doesn't mean that they are actually implemented this way, regardless of what the language spec says. It's alarming that this guy apparently writes books, hopefully no one reads them.