create the :42 feature bundle

The FEATURE_BUNDLE_xxx constants in feature.h must be ordered by
version. The 'as_bundles' sort function ensures that all bundles will
be sorted correctly (except for 5.9.5, which ends up between 5.41 and 41).

regen/feature.pl

@@ -107,8 +107,18 @@ BEGIN
     "5.39"  => [ +V5_39 ],
     # using 5.41 features bundle
     "5.41"  => [ +V5_41 ],
+    # using 41 features bundle
+    "41"    => [ +V5_41 ],
 );
 
+# actually, 5.9.5 ends up between 5.41 and 41
+sub as_bundles {
+     $a eq 'default' ? -1 : $b eq 'default'   ?  1 # default first
+   : $a eq 'all'     ?  1 : $b eq 'all'       ? -1 # all last
+   : $a =~ /\./      ? $b =~ /\./ ? $a cmp $b : -1 # 5.x in order, before
+   :                   $b =~ /\./ ? 1 : $a <=> $b; # integers in order
+}
+
 my @noops = qw( postderef lexical_subs );
 my @removed = qw( array_base switch );
 
@@ -128,13 +138,18 @@ BEGIN
 }
 
 for (keys %feature_bundle) {
-    next unless /^5\.(\d*[13579])\z/;
-    $feature_bundle{"5.".($1+1)} ||= $feature_bundle{$_};
+    if (/^5\.(\d*[13579])\z/) { # 5.x dev series
+        $feature_bundle{"5.".($1+1)} ||= $feature_bundle{$_};
+    }
+    elsif (/^([4-9][13579]|[1-9][0-9]+[13579])\z/) { # 41 and above
+        $feature_bundle{($1+1)} ||= $feature_bundle{$_};
+    }
 }
+delete $feature_bundle{"5.42"}; # this one does not exist
 
 my %UniqueBundles; # "say state switch" => 5.10
 my %Aliases;       #  5.12 => 5.11
-for( sort keys %feature_bundle ) {
+for( sort as_bundles keys %feature_bundle ) {
     my $value = join(' ', sort @{$feature_bundle{$_}});
     if (exists $UniqueBundles{$value}) {
 	$Aliases{$_} = $UniqueBundles{$value};
@@ -146,8 +161,7 @@ BEGIN
 			   # start   end
 my %BundleRanges; # say => ['5.10', '5.15'] # unique bundles for values
 for my $bund (
-    sort { $a eq 'default' ? -1 : $b eq 'default' ? 1 : $a cmp $b }
-         values %UniqueBundles
+    sort as_bundles values %UniqueBundles
 ) {
     next if $bund =~ /[^\d.]/ and $bund ne 'default';
     for (@{$feature_bundle{$bund}}) {
@@ -193,7 +207,7 @@ BEGIN
 die "No HINT_UNI_8_BIT defined in perl.h"    unless $Uni8Bit;
 
 my @HintedBundles =
-    ('default', grep !/[^\d.]/, sort values %UniqueBundles);
+    ('default', grep !/[^\d.]/, sort as_bundles values %UniqueBundles);
 
 
 ###########################################################################
@@ -240,7 +254,7 @@ sub longest {
 }
 print $pm ");\n\n";
 
-for (sort keys %Aliases) {
+for (sort as_bundles keys %Aliases) {
     print $pm
 	qq'\$feature_bundle{"$_"} = \$feature_bundle{"$Aliases{$_}"};\n';
 };
@@ -277,7 +291,7 @@ sub longest {
 $::bundle, $::feature
 .
 
-for ('default', sort grep /\.\d[02468]/, keys %feature_bundle) {
+for ('default', sort as_bundles grep /[02468]\z/, keys %feature_bundle) {
     $::bundle = ":$_";
     $::feature = join ' ', @{$feature_bundle{$_}};
     write $pm;