I just wrote about implementing abo-abo’s solution for having multiple Info buffers and in particular his using the gcl Info file as a substitute for the Common Lisp HyperSpec. I really wanted to try that out so I downloaded the tar file from the link that he provided and installed it in my .emacs.d directory. Then, as abo-abo explained, I added ~/.emacs.d/info to the Info-additional-directory-list variable.
Sadly, it didn’t work. I asked abo-abo for his wisdom on the matter and he suggested that I just push the .emacs.d/info directory directly onto the Info-directory-list. I tried that and it didn’t work either. I could get to it with the standalone Info reader by using the -f option but couldn’t get to it from Emacs.
The problem was that the gcl file was not being added to the dir file that serves as the top node for Info. The proper way to do that is to run install-info. In my case
sudo install-info gcl.info /usr/share/info/dir
Annoyingly, it still didn’t work. It turns out that install-info extracts data from the Info file you’re installing to update the dir file. For some reason the gcl.info file didn’t have the required information. I adapted the information from the sbcl.info file, added it do gcl.info, reran install-info, and everything worked fine. Unless you’re trying to use the gcl.info that abo-abo linked to, you don’t have to worry about that; just run install-info.
If you’re trying to install the gcl file, here is what you need to add to the top of gcl.info
INFO-DIR-SECTION Software development START-INFO-DIR-ENTRY * gcl: (gcl). The GNU Common Lisp compiler END-INFO-DIR-ENTRY