Contains various options that can control preprocessing behavior.
- The maximum depth of the include stack; further attempts to include a file will result in an error.
- The name to associate with errors produced by macros specified via the predefines option.
vector<std:: string> predefines
- A set of macros to predefine, of the form <macro>=<value> or just <macro> to predefine to a value of 1.
vector<std:: string> undefines
- A set of macro names to undefine at the start of file preprocessing.
- A set of preprocessor directives to be ignored.