--- a/build-aux/texinfo.tex
+++ b/build-aux/texinfo.tex
@@ -3,7 +3,7 @@
 % Load plain if necessary, i.e., if running under initex.
 \expandafter\ifx\csname fmtname\endcsname\relax\input plain\fi
 %
-\def\texinfoversion{2014-05-20.16}
+\def\texinfoversion{2014-10-29.10}
 %
 % Copyright 1985, 1986, 1988, 1990, 1991, 1992, 1993, 1994, 1995,
 % 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006,
@@ -5739,13 +5739,16 @@
 %
 % #1 is the text, #2 is the section type (Ynumbered, Ynothing,
 % Yappendix, Yomitfromtoc), #3 the chapter number.
+% Not used for @heading series.
 %
 % To test against our argument.
 \def\Ynothingkeyword{Ynothing}
+\def\Yappendixkeyword{Yappendix}
 \def\Yomitfromtockeyword{Yomitfromtoc}
-\def\Yappendixkeyword{Yappendix}
 %
 \def\chapmacro#1#2#3{%
+  \checkenv{}% chapters, etc., should not start inside an environment.
+  %
   % Insert the first mark before the heading break (see notes for \domark).
   \let\prevchapterdefs=\lastchapterdefs
   \let\prevsectiondefs=\lastsectiondefs
@@ -5891,22 +5894,28 @@
 
 % Print any size, any type, section title.
 %
-% #1 is the text, #2 is the section level (sec/subsec/subsubsec), #3 is
-% the section type for xrefs (Ynumbered, Ynothing, Yappendix), #4 is the
-% section number.
+% #1 is the text of the title,
+% #2 is the section level (sec/subsec/subsubsec),
+% #3 is the section type (Ynumbered, Ynothing, Yappendix, Yomitfromtoc),
+% #4 is the section number.
 %
 \def\seckeyword{sec}
 %
 \def\sectionheading#1#2#3#4{%
   {%
-    \checkenv{}% should not be in an environment.
+    \def\sectionlevel{#2}%
+    \def\temptype{#3}%
+    %
+    % It is ok for the @heading series commands to appear inside an
+    % environment (it's been historically allowed, though the logic is
+    % dubious), but not the others.
+    \ifx\temptype\Yomitfromtockeyword\else
+      \checkenv{}% non-@*heading should not be in an environment.
+    \fi
     %
     % Switch to the right set of fonts.
     \csname #2fonts\endcsname \rmisbold
     %
-    \def\sectionlevel{#2}%
-    \def\temptype{#3}%
-    %
     % Insert first mark before the heading break (see notes for \domark).
     \let\prevsectiondefs=\lastsectiondefs
     \ifx\temptype\Ynothingkeyword