diff --git a/perl/lib/Data/MessagePack/PP.pm b/perl/lib/Data/MessagePack/PP.pm
index f179ad74..74fe8866 100644
--- a/perl/lib/Data/MessagePack/PP.pm
+++ b/perl/lib/Data/MessagePack/PP.pm
@@ -211,6 +211,9 @@ sub _pack {
         }
 
     }
+    elsif ( $flags & ( B::SVf_NOK | B::SVp_NOK ) ) { # double only
+        return pack_double( $value );
+    }
     elsif ( $flags & B::SVf_POK ) { # raw / check needs before dboule
 
         if ( $Data::MessagePack::PreferInteger ) {
@@ -242,9 +245,6 @@ sub _pack {
         return $header . $value;
 
     }
-    elsif ( $flags & ( B::SVf_NOK | B::SVp_NOK ) ) { # double only
-        return pack_double( $value );
-    }
     else {
         _unexpected("data type %s", $b_obj);
     }
diff --git a/perl/t/01_pack.t b/perl/t/01_pack.t
index 8c619809..8293bbbf 100644
--- a/perl/t/01_pack.t
+++ b/perl/t/01_pack.t
@@ -10,14 +10,30 @@ sub packit {
 }
 
 sub pis ($$) {
+    local $Test::Builder::Level = $Test::Builder::Level + 1;
     is packit($_[0]), $_[1], 'dump ' . $_[1];
 }
 
+sub PVIV_but_not_POK_nor_IOK {
+    no warnings 'void';
+    my $foo = 42;
+    "$foo"; # upgrade to PVIV
+    $foo = undef;
+    return $foo;
+}
+
+sub upgrade_to_PVXV {
+    my($n) = @_;
+    no warnings 'void';
+    "$n";
+    return $n;
+}
+
+
 my @dat = (
     0,     '00',
     (my $foo="0")+0, '00',
     {2 => undef}, '81 a1 32 c0',
-    do {no warnings; my $foo = 10; "$foo"; $foo = undef; $foo} => 'c0', # PVIV but !POK && !IOK
     1,     '01',
     127,   '7f',
     128,   'cc 80',
@@ -33,12 +49,16 @@ my @dat = (
     -32768, 'd1 80 00',
     -32769, 'd2 ff ff 7f ff',
     1.0,   'cb 3f f0 00 00 00 00 00 00',
-    do { my $x=3.0;my $y = "$x";$x },   'a1 33', # PVNV
+    upgrade_to_PVXV( 1),   '01',
+    upgrade_to_PVXV(-1),   'ff',
+    upgrade_to_PVXV(3.0), 'cb 40 08 00 00 00 00 00 00',
     "",    'a0',
     "a",   'a1 61',
     "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa", 'bf 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61',
     "aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa", 'da 00 20 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61 61',
+
     undef, 'c0',
+    PVIV_but_not_POK_nor_IOK(), 'c0',
     Data::MessagePack::true(), 'c3',
     Data::MessagePack::false(), 'c2',
     [], '90',
diff --git a/perl/xs-src/pack.c b/perl/xs-src/pack.c
index 862808eb..97ae045c 100644
--- a/perl/xs-src/pack.c
+++ b/perl/xs-src/pack.c
@@ -152,17 +152,7 @@ STATIC_INLINE void _msgpack_pack_sv(enc_t* const enc, SV* const sv, int const de
     if (UNLIKELY(depth <= 0)) Perl_croak(aTHX_ ERR_NESTING_EXCEEDED);
     SvGETMAGIC(sv);
 
-    if (SvPOKp(sv)) {
-        STRLEN const len     = SvCUR(sv);
-        const char* const pv = SvPVX_const(sv);
-
-        if (s_pref_int && try_int(enc, pv, len)) {
-            return;
-        } else {
-            msgpack_pack_raw(enc, len);
-            msgpack_pack_raw_body(enc, pv, len);
-        }
-    } else if (SvNIOKp(sv)) {
+    if (SvNIOKp(sv)) {
         if(SvUOK(sv)) {
             PACK_UV(enc, SvUVX(sv));
         }
@@ -173,6 +163,16 @@ STATIC_INLINE void _msgpack_pack_sv(enc_t* const enc, SV* const sv, int const de
             /* XXX long double is not supported yet. */
             msgpack_pack_double(enc, (double)SvNVX(sv));
         }
+    } else if (SvPOKp(sv)) {
+        STRLEN const len     = SvCUR(sv);
+        const char* const pv = SvPVX_const(sv);
+
+        if (s_pref_int && try_int(enc, pv, len)) {
+            return;
+        } else {
+            msgpack_pack_raw(enc, len);
+            msgpack_pack_raw_body(enc, pv, len);
+        }
     } else if (SvROK(sv)) {
         _msgpack_pack_rv(enc, SvRV(sv), depth-1);
     } else if (!SvOK(sv)) {
@@ -233,9 +233,9 @@ STATIC_INLINE void _msgpack_pack_rv(enc_t *enc, SV* sv, int depth) {
         char *pv = svt ? SvPV (sv, len) : 0;
 
         if (len == 1 && *pv == '1')
-            msgpack_pack_true(enc); 
+            msgpack_pack_true(enc);
         else if (len == 1 && *pv == '0')
-            msgpack_pack_false(enc); 
+            msgpack_pack_false(enc);
         else {
             //sv_dump(sv);
             croak("cannot encode reference to scalar '%s' unless the scalar is 0 or 1",