This may fix `perlbrew env` endless loop when some component in PERLBREW_ROOT is symlinks

fix-perlbrew.patch

diff --git a/lib/App/perlbrew.pm b/lib/App/perlbrew.pm
index 808a49f..c281399 100644
--- a/lib/App/perlbrew.pm
+++ b/lib/App/perlbrew.pm
@@ -7,6 +7,7 @@ our $VERSION = "0.57";
 use Config;
 use Capture::Tiny;
 use Getopt::Long ();
+use Cwd 'realpath';
 use File::Spec::Functions qw( catfile catdir );
 use File::Basename;
 use File::Path ();
@@ -202,6 +203,13 @@ sub installed_perl_executable {
     return "";
 }
 
+sub installed_perl_prefix {
+    my ($self, $name) = @_;
+    my $prefix = realpath(catdir($self->root, "perls", $name));
+    return $prefix if -e $prefix;
+    return "";
+}
+
 sub cpan_mirror {
     my ($self, $v) = @_;
     unless($self->{cpan_mirror}) {
@@ -1454,19 +1462,12 @@ sub run_command_env {
 
     if ($name) {
         my($perl_name,$lib_name) = $self->resolve_installation_name($name);
-        my $target_perl_executable = $self->installed_perl_executable($perl_name);
-
-        my $link_count = 1;
-        while (-l $target_perl_executable) {
-            $target_perl_executable = readlink($target_perl_executable);
-            $link_count++;
-            if ($link_count++ > 100) {
-                die "Problematic symlink detected: $target_perl_executable";
-            }
-        }
+        my $target_perl_exe = $self->installed_perl_executable($perl_name);
+
+        my $is_target_perl = $self->installed_perl_prefix($perl_name) eq realpath($Config{installprefix});
 
-        if ($target_perl_executable && $perl_name && $^X ne $target_perl_executable && -x $target_perl_executable && -x $0) {
-            exec($target_perl_executable, $0, "env", $name);
+        if ($perl_name && $is_target_perl && -x $target_perl_exe && -x $0) {
+            exec($target_perl_exe, $0, "env", $name);
         }
     }