From 3a4360acc2f1d369c3fd66aaf199bbd577614797 Mon Sep 17 00:00:00 2001
From: Raja R Harinath <harinath@acm.org>
Date: Thu, 10 Jul 2003 23:39:09 +0000
Subject: [PATCH] Avoid using refs as hash keys. * lib/Automake/Variable.pm
 ($_traversal): New. (reset): Reset $_traversal. (_new): New attribute
 'scanned'. (%_vars_scanned): Remove. (traverse_variable_recursively)
 (traverse_variable_recursively_worker): Use $_traversal instead of
 %_vars_scanned to detect recursively defined variables.

---
 ChangeLog                | 10 ++++++++++
 lib/Automake/Variable.pm | 18 ++++++++++--------
 2 files changed, 20 insertions(+), 8 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index a9e955d4..78ed0992 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,15 @@
 2003-07-10  Raja R Harinath  <harinath@cs.umn.edu>
 
+	Avoid using refs as hash keys.
+	* lib/Automake/Variable.pm ($_traversal): New.
+	(reset): Reset $_traversal.
+	(_new): New attribute 'scanned'.
+	(%_vars_scanned): Remove.
+	(traverse_variable_recursively)
+	(traverse_variable_recursively_worker):
+	Use $_traversal instead of %_vars_scanned to detect recursively
+	defined variables.
+
 	* lib/am/configure.am (am--refresh): Silence.
 
 2003-07-10  Alexandre Duret-Lutz  <adl@gnu.org>
diff --git a/lib/Automake/Variable.pm b/lib/Automake/Variable.pm
index c8d07b25..6944cea9 100644
--- a/lib/Automake/Variable.pm
+++ b/lib/Automake/Variable.pm
@@ -191,6 +191,10 @@ my %_silent_variable_override =
 # the named of the helper variable used to append to VAR in CONDITIONS.
 my %_appendvar = ();
 
+# Each call to C<traverse_variable_recursively> gets an unique label.
+# This is used to detect recursively defined variables.
+my $_traversal = 0;
+
 
 =head2 Error reporting functions
 
@@ -311,6 +315,7 @@ sub reset ()
   %_appendvar = ();
   @_var_order = ();
   %_gen_varname = ();
+  $_traversal = 0;
 }
 
 =item C<var ($varname)>
@@ -407,6 +412,7 @@ sub _new ($$)
     name => $name,
     defs => {},
     conds => {},
+    scanned => 0,
   };
   bless $self, $class;
   $_variable_dict{$name} = $self;
@@ -1457,13 +1463,9 @@ calls).
 # substitutions currently in force.
 my @_substfroms;
 my @_substtos;
-# This is used to keep track of which variable definitions we are
-# scanning.
-my %_vars_scanned = ();
-
 sub traverse_variable_recursively ($&&;$)
 {
-  %_vars_scanned = ();
+  ++$_traversal;
   @_substfroms = ();
   @_substtos = ();
   my ($var, $fun_item, $fun_collect, $cond_filter) = @_;
@@ -1483,12 +1485,12 @@ sub _traverse_variable_recursively_worker ($$&&$$)
   return ()
     unless $var;
 
-  if (defined $_vars_scanned{$var})
+  if ($var->{'scanned'} == $_traversal)
     {
       err_var $var, "variable `" . $var->name() . "' recursively defined";
       return ();
     }
-  $_vars_scanned{$var} = 1;
+  $var->{'scanned'} = $_traversal;
 
   my @allresults = ();
   my $cond_once = 0;
@@ -1567,7 +1569,7 @@ sub _traverse_variable_recursively_worker ($$&&$$)
 
   # We only care about _recursive_ variable definitions.  The user
   # is free to use the same variable several times in the same definition.
-  delete $_vars_scanned{$var};
+  $var->{'scanned'} = -1;
 
   # Make sure you update the doc of &traverse_variable_recursively
   # if you change the prototype of &fun_collect.
-- 
2.43.5