doc update.

[marc-alexandre autret]

This patch updates doc about %{source,header}_extension directives
which will be turn on soon.
It also add explaination about YYSTACK_USE_ALLOCA.

------------------------------------------------------------------------
--- ../../bison/doc/bison.texinfo       Mon Aug 13 16:54:50 2001
+++ bison.texinfo       Tue Aug 14 12:09:50 2001
@@ -3039,6 +3039,21 @@
 be able to refer to token type codes and the variable
 @code{yylval}.  @xref{Token Values, ,Semantic Values of address@hidden
 
address@hidden %source_extension
+Specify the extension of the parser output file.
+
+For example, a grammar file named @file{foo.yy} and containing a 
address@hidden .cpp} directive will produce a parser file
+named @file{foo.tab.cpp}
+
address@hidden %header_extension
+Specify the extension of the parser header file generated when 
address@hidden or @samp{-d} are used.
+
+For example, a garmmar file named @file{foo.ypp} and containing a 
address@hidden .hh} directive will produce a header file
+named @file{foo.tab.hh}
+
 @item %verbose
 Write an extra output file containing verbose descriptions of the
 parser states and what is done for each type of look-ahead token in
@@ -5046,6 +5061,12 @@
 Macro whose value indicates whether the parser is recovering from a
 syntax error.  @xref{Action Features, ,Special Features for Use in Actions}.
 
address@hidden YYSTACK_USE_ALLOCA
+Macro used to control the use of @code{alloca}. If defined with null value, 
+disables @code{alloca} using. If defined with another value, forces 
address@hidden using. In the case you do not define it, @code{alloca} will be 
+used if found on the system else it will be @code{malloc}. 
+
 @item YYSTYPE
 Macro for the data type of semantic values; @code{int} by default.
 @xref{Value Type, ,Data Types of Semantic Values}.
@@ -5108,6 +5129,14 @@
 @item %defines
 Bison declaration to create a header file meant for the scanner.
 @xref{Decl Summary}.
+
address@hidden %source_extension
+Bison declaration to specify the generated parser output file extension. 
address@hidden Summary}.
+
address@hidden %header_extension
+Bison declaration to specify the generated parser header file extension
+if required. @xref{Decl Summary}.
 
 @item %left
 Bison declaration to assign left associativity to token(s).
-----------------------------------------------------------------------

-- 
Autret Marc (address@hidden)
Eleve Ingenieur en Informatique