Important reminder just in the Preface :-) Takeaway #1: "C and C++ are different: don’t mix them, and don’t mix them up"
Specially relevant to all those folks that insist on "Coding C with a C++ compiler", instead of safer language constructs, and standard library alternatives provided by C++ during the last decades.
This is how I managed to sneak C++ into an embedded C codebase. We even created some templates for data structures that supported static allocation at compile time.