texinfo.tex version 2016-05-07.20 (the current version in Gnulib) causes 
what appears to be runaway recursion when used to make PDF files for GNU 
Emacs. The Emacs bug report is here:

http://bugs.gnu.org/23611

To reproduce the problem on a Fedora 23 x86-64 machine with build tools 
installed, you can run these shell commands:

git clone git://git.savannah.gnu.org/emacs.git emacs-bug
cd emacs-bug
git checkout 1ee91bf89176251f6e399c8436dca0248cdd6f6b
./autogen.sh all
./configure
make pdf

A build transcript is attached.

The problem goes away if I substitute the previous texinfo.tex version, 
2016-04-14.07.

Are recent and near-future texinfo.tex changes relevant for Emacs 
documentation? If not we should probably just freeze emacs-25 based on 
texinfo.tex 2016-04-14.07, since we're close to a release.