Index: texinfo.tex
===================================================================
--- texinfo.tex	(revision 6493)
+++ texinfo.tex	(working copy)
@@ -7460,7 +7460,9 @@
 
 \def\macroargctxt{% used when scanning invocations
   \scanctxt
-  \catcode`\\=0
+  \catcode`\ =\other
+  \catcode`\\=\active
+  %\catcode`\\=0
 }
 % why catcode 0 for \ in the above?  To recognize \\ \{ \} as "escapes"
 % for the single characters \ { }.  Thus, we end up with the "commands"
@@ -7907,16 +7909,52 @@
 
 \def\norecurse#1{\bgroup\cslet{#1}{macsave.#1}}
 
+% Call #1 with a list of tokens #2, with any doubled backslashes in #2
+% compressed to one.
+\def\passargtomacro#1#2{%
+% Append an unexpandable token to #2, to allows a trailing
+% active backslash in the argument not to eat the next token.
+\let\macroargdummy=\relax
+\def\arg{#2\macroargdummy}%
+%
+% Expand the arg list.  There won't be unwanted expansion of control sequences 
+% in the argument because the arg was read with the catcode of @ as \other.
+\let\resultingbackslash=\relax % prevent expansion
+\usemacroargbackslash
+\macroargctxt
+\def\macroargdummy{}%
+\edef\arg{\arg}%
+\expandafter#1\expandafter{\arg}%
+}
+
+% use active definition of backslash at time of expansion
+\def\resultingbackslash{\activebackslash}
+
+% \macroargbackslash
+% - expand \\ and single \ as \resultingbackslash
+{ address@hidden @address@hidden@active
address@hidden@macroargbackslash#1{%
+% we need noexpand because \ is active
address@hidden @noexpand address@hidden address@hidden
address@hidden @resultingbackslash #1%
address@hidden
+
address@hidden@address@hidden@macroargbackslash}
+}
+
+
 % \braceorline MAC is used for a one-argument macro MAC.  It checks
 % whether the next non-whitespace character is a {.  It sets the context
 % for reading the argument (slightly different in the two cases).  Then,
-% to read the argument, in the whole-line case, it then calls the
-% regular \parsearg MAC; in the lbrace case, it just calls MAC itself.
+% to read the argument, in the whole-line case, it then calls the regular
+% \parsearg MAC; in the lbrace case, it calls \passargtomacro MAC.
 % 
 \def\braceorline#1{\let\macnamexxx=#1\futurelet\nchar\braceorlinexxx}
 \def\braceorlinexxx{%
-  \ifx\nchar\bgroup\macroargctxt
-  \else\macrolineargctxt\expandafter\parsearg
+  \ifx\nchar\bgroup
+    \macroargctxt\expandafter\passargtomacro
+  \else
+    \macrolineargctxt\expandafter\parsearg
   \fi \macnamexxx}
 
 
@@ -10292,7 +10330,10 @@
 % catcode other.  We switch back and forth between these.
 @address@hidden@address@hidden
 @address@hidden@address@hidden
address@hidden@address@hidden@normalbackslash}
 
address@hidden@address@hidden @address@hidden
+
 @address@hidden@address@hidden@address@hidden
 
 % Same as @turnoffactive except outputs \ as {\tt\char`\\} instead of