Add 'private' variable modifier, feature submitted by Ramon Garcia.

Rework the parser for variables to allow multiple modifiers and also
allow for variables and targets with modifier names, like "export" and
"private".

ChangeLog

@@ -1,3 +1,18 @@
+2009-05-25  Paul Smith  <psmith@gnu.org>
+
+	Reworked the parser for variable assignments to allow multiple
+	modifiers, and in any order.  Also allows variable and
+	prerequisites to be modifier names ('export', 'private', etc.)
+
+	* NEWS: Add notes about user-visible changes.
+
+	* read.c (struct vmodifiers): Remember what modifiers were seen.
+	(parse_var_assignment): New function to parse variable assignments.
+	(eval): Call the new function.  Handle variable assignments earlier.
+
+	* variable.c (parse_variable_definition): Only parse; don't create var.
+	(assign_variable_definition): Call parse, then create the var.
+
 2009-05-24  Paul Smith  <psmith@gnu.org>
 
 	* doc/make.texi: Fix the ISBN for the GNU make manual.  Incorrect
@@ -23,6 +38,21 @@
 	* function.c (func_shell): Don't close pipedes[1] if it is -1.
 	Fixes Savannah bug #20495.
 
+2009-02-23  Ramon Garcia  <ramon.garcia.f@gmail.com>
+
+	Introduce a new keyword "private" which applies to target-specific
+	variables and prevents their values from being inherited.
+
+	* variable.h (struct variable): Add private_var flag to each variable.
+	Add a flag to specify which list entry switches to the parent target.
+	* variable.c (define_variable_in_set): Initialize private_var flag.
+	(lookup_variable): Skip private variables in parent contexts.
+	(initialize_file_variables): Set next_is_parent appropriately.
+	(print_variable): Show the private_var flag.
+	* read.c (eval): Recognize the private keyword.
+	(record_target_var): Set private_var.
+	* doc/make.texi (Suppressing Inheritance): Add documentation.
+
 2008-10-26  Paul Smith  <psmith@gnu.org>
 
 	* configure.in: Check for strndup().