C++ Primer Plus

Specifiers and Qualifiers

Certain C++ keywords, called storage class specifiers and cv-qualifiers, provide additional information about storage. Here’s a list of the storage class specifiers:

auto (eliminated as a specifier in C++11)registerstaticexternthread_local (added by C++11)mutable

You’ve already seen most of these, and you can use no more than one of them in a single declaration, except that thread_local can be used with static or extern. To review, prior to C++11, the keyword auto could be used in a declaration to document that the variable is an automatic variable. (In C++11, auto is used for automatic type deduction.) The keyword register is used in a declaration to indicate the register storage class, which, in C++11, simply is an ...