Imported from ../bash-3.2.48.tar.gz.

doc/bash.1

@@ -7977,6 +7977,12 @@ attempts to save all lines of a multiple-line
 command in the same history entry.  This allows
 easy re-editing of multi-line commands.
 .TP 8
+.B compat31
+If set,
+.B bash
+changes its behavior to that of version 3.1 with respect to quoted
+arguments to the conditional command's =~ operator.
+.TP 8
 .B dotglob
 If set, 
 .B bash