4 files changed, 43 insertions, 4 deletions
diff --git a/t/comp/hints.t b/t/comp/hints.t
index 117096860f..f00bb6a893 100644
--- a/t/comp/hints.t
+++ b/t/comp/hints.t
@@ -2,7 +2,13 @@
 
 # Tests the scoping of $^H and %^H
 
-BEGIN { print "1..14\n"; }
+BEGIN {
+    chdir 't' if -d 't';
+    @INC = qw(. ../lib);
+}
+
+
+BEGIN { print "1..15\n"; }
 BEGIN {
     print "not " if exists $^H{foo};
     print "ok 1 - \$^H{foo} doesn't exist initially\n";
@@ -55,3 +61,15 @@ BEGIN {
     print "not " if $^H & 0x00020000;
     print "ok 8 - \$^H doesn't contain HINT_LOCALIZE_HH while finishing compilation\n";
 }
+
+require 'test.pl';
+
+# bug #27040: hints hash was being double-freed
+my $result = runperl(
+    prog => '$^H |= 0x20000; eval q{BEGIN { $^H |= 0x20000 }}',
+    stderr => 1
+);
+print "not " if length $result;
+print "ok 15 - double-freeing hints hash\n";
+print "# got: $result\n" if length $result;
+
diff --git a/t/op/magic.t b/t/op/magic.t
index dda07dfbc9..1c02b5bbad 100755
--- a/t/op/magic.t
+++ b/t/op/magic.t
@@ -349,7 +349,7 @@ else {
 }
 
 if ($Is_miniperl) {
-    skip ("miniperl can't rely on loading %Errno");
+    skip ("miniperl can't rely on loading %Errno") for 1..2;
 } else {
    no warnings 'void';
 
diff --git a/t/op/ref.t b/t/op/ref.t
index 3bb280c1ea..597e03698c 100755
--- a/t/op/ref.t
+++ b/t/op/ref.t
@@ -5,7 +5,7 @@ BEGIN {
     @INC = qw(. ../lib);
 }
 
-print "1..68\n";
+print "1..69\n";
 
 require 'test.pl';
 
@@ -357,6 +357,16 @@ runperl(prog => 'sub f { my $x = shift; *z = $x; } f({}); f();');
 if ($? != 0) { print "not " };
 print "ok ",++$test," - coredump on typeglob = (SvRV && !SvROK)\n";
 
+# bug #27268: freeing self-referential typeglobs could trigger
+# "Attempt to free unreferenced scalar" warnings
+
+$result = runperl(
+    prog => 'use Symbol;my $x=bless \gensym,"t"; print;*$$x=$x',
+    stderr => 1
+);
+print "not " if length $result;
+print "ok ",++$test," - freeing self-referential typeglob\n";
+print "# got: $result\n" if length $result;
 
 # test global destruction
 
diff --git a/t/op/substr.t b/t/op/substr.t
index dfb483aee5..4df6426388 100755
--- a/t/op/substr.t
+++ b/t/op/substr.t
@@ -1,6 +1,6 @@
 #!./perl
 
-print "1..177\n";
+print "1..179\n";
 
 #P = start of string  Q = start of substr  R = end of substr  S = end of string
 
@@ -609,3 +609,14 @@ ok 174, $x eq "\x{100}\x{200}\xFFb";
     my $y = substr $x, 4;
     ok 177, substr($x, 7, 1) eq "7";
 }
+
+# [perl #24200] string corruption with lvalue sub
+
+{
+    my $foo = "a";
+    sub bar: lvalue { substr $foo, 0 }
+    bar = "XXX";
+    ok 178, bar eq 'XXX';
+    $foo = '123456789';
+    ok 179, bar eq '123456789';
+}