compilation-get-file-structure

compilation-get-file-structure is a compiled Lisp function in `compile.el'.

(compilation-get-file-structure FILE &optional FMT)

Retrieve FILE's file-structure or create a new one.
FILE should be (FILENAME) or (RELATIVE-FILENAME . DIRNAME).
In the former case, FILENAME may be relative or absolute.

The file-structure looks like this:
((FILENAME [DIR-FROM-PREV-MSG]) FMT LINE-STRUCT...)