From a2ed1d51f8a4769376176ead6b719ecc3434457d Mon Sep 17 00:00:00 2001
From: Alexander Konovalov <alexk@mcs.st-andrews.ac.uk>
Date: Thu, 19 Mar 2015 13:59:29 +0000
Subject: [PATCH] Made LARGEST_IDENTIFIER_NUMBER a fixed atomic list.

This fixed ctblmono.tst run in the background thread.
---
 lib/ctbl.gd | 2 +-
 lib/ctbl.gi | 3 +--
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/lib/ctbl.gd b/lib/ctbl.gd
index abbee9b3a0..96511067bb 100644
--- a/lib/ctbl.gd
+++ b/lib/ctbl.gd
@@ -1644,7 +1644,7 @@ DeclareAttributeSuppCT( "Identifier", IsNearlyCharacterTable, [] );
 DeclareGlobalVariable( "LARGEST_IDENTIFIER_NUMBER",
     "list containing the largest identifier of an ordinary character table\
  in the current session" );
-InstallFlushableValue( LARGEST_IDENTIFIER_NUMBER, [ 0 ] );
+InstallValue( LARGEST_IDENTIFIER_NUMBER, FixedAtomicList([ 0 ]) );
 
 
 #############################################################################
diff --git a/lib/ctbl.gi b/lib/ctbl.gi
index 08462f9e4a..efb9652f28 100644
--- a/lib/ctbl.gi
+++ b/lib/ctbl.gi
@@ -2515,8 +2515,7 @@ InstallMethod( Identifier,
     function( tbl )
 
     # Construct an identifier that is unique in the current session.
-    LARGEST_IDENTIFIER_NUMBER[1]:= LARGEST_IDENTIFIER_NUMBER[1] + 1;
-    tbl:= Concatenation( "CT", String( LARGEST_IDENTIFIER_NUMBER[1] ) );
+    tbl:= Concatenation( "CT", String( ATOMIC_ADDITION( LARGEST_IDENTIFIER_NUMBER, 1, 1 ) ) );
     ConvertToStringRep( tbl );
     return tbl;
     end );