decl-specifier = storage-class-specifier | function-specifier | type-specifier | "friend" | "typedef" . storage-class-specifier = "auto" | "register" | "static" | "extern" | "mutable" . function-specifier = "inline" | "virtual" | "explicit". type-specifier = cv-qualifier | simple-type-specifier | class-specifier | enum-specifier | elaborated-type-specifier . cv-qualifier = "const" | "volatile" . simple-type-specifier = "bool" | "char" | "int" | "wchar_t" | "double" | "float" | "void" "long" | "short" | "signed" | "unsigned" | type-name . type-name = class-name | enum-name | typedef-name .