Maxima should handle a missing info file more gracefully:
Maxima 5.36.1 http://maxima.sourceforge.net using Lisp GNU Common Lisp (GCL) GCL 2.6.12 Distributed under the GNU Public License. See the file COPYING. Dedicated to the memory of William Schelter. The function bug_report() provides bug reporting information. (%i1) ? riemann Maxima encountered a Lisp error: Condition in MACSYMA-TOP-LEVEL [or a callee]: INTERNAL-SIMPLE-ERROR: Cannot open the file /usr/share/doc/maxima/info/./maxima.info-1. Automatically continuing. To enable the Lisp debugger set *debugger-hook* to nil.
Here's a patch for this. Let me know what you think of it.
I think this might be fixed already (with the patch shown above or one very similar); needs review.
Oh boy! Thanks Roy. I pushed the fix in commit 7614fd0f0