20.5 Pointer Validation

If you do not suppress pointer validation with the ‘--no-validate’ option or the @novalidate command in the source file (see Use TeX), makeinfo will check the validity of the Texinfo file.

Most validation checks are different depending on whether node pointers are explicitly or implicitly determined. With explicit node pointers, here is the list of what is checked:

1. If a ‘Next’, ‘Previous’, or ‘Up’ node reference is a reference to a node in the current file and is not an external reference such as to (dir), then the referenced node must exist.
2. Every node except the ‘Top’ node must have an ‘Up’ pointer.
3. The node referenced by an ‘Up’ pointer must itself reference the current node through a menu item, unless the node referenced by ‘Up’ has the form ‘(file)’.

With implicit node pointers, the above error cannot occur, as such. (Which is a major reason why we recommend using this feature of makeinfo, and not specifying any node pointers yourself.)

Instead, makeinfo checks that the tree constructed from the document’s menus matches the tree constructed from the sectioning commands. For example, if a chapter-level menu mentions nodes n1 and n2, in that order, nodes n1 and n2 must be associated with @section commands in the chapter.

Finally, with both explicit and implicit node pointers, makeinfo checks that every node except the ‘Top’ node is referenced in a menu.