Getting the "explanation" part of the current error message

[Nordlöw]

Hi!

I'm looking for a way to take the "explanation" part of a (GCC or
other) compilation info/warning/error message and display it
separately in the minibuffer or as a tooltip near the problem source
code line.

I have looked at the sources simple.el compile.el specifically at
compilation-next-error-function() but I don't find any structure that
contains the (pre-)parsed messages of the compilation-buffer contents.
Does such a structure exists? If so we could extended it with the
"explanation" part and visualize in next-error-hook. If not I guess we
need to use compilation-error-regexp-alist-alist and to separately
parse the compilation-buffer, right?

/Nordlöw