--- JSON-XS/XS.xs	2013/10/29 00:06:40	1.121
+++ JSON-XS/XS.xs	2016/02/21 15:37:53	1.125
@@ -19,6 +19,17 @@
 # define UTF8_MAXBYTES 13
 #endif
 
+// compatibility with perl <5.18
+#ifndef HvNAMELEN_get
+# define HvNAMELEN_get(hv) strlen (HvNAME (hv))
+#endif
+#ifndef HvNAMELEN
+# define HvNAMELEN(hv) HvNAMELEN_get (hv)
+#endif
+#ifndef HvNAMEUTF8
+# define HvNAMEUTF8(hv) 0
+#endif
+
 // three extra for rounding, sign, and end of string
 #define IVUV_MAXCHARS (sizeof (UV) * CHAR_BIT * 28 / 93 + 3)
 
@@ -709,7 +720,9 @@
           int count;
           dSP;
 
-          ENTER; SAVETMPS; PUSHMARK (SP);
+          ENTER; SAVETMPS;
+          SAVESTACK_POS ();
+          PUSHMARK (SP);
           EXTEND (SP, 2);
           // we re-bless the reference to get overload and other niceties right
           PUSHs (sv_bless (sv_2mortal (newRV_inc (sv)), stash));
@@ -721,7 +734,7 @@
 
           // catch this surprisingly common error
           if (SvROK (TOPs) && SvRV (TOPs) == sv)
-            croak ("%s::TO_JSON method returned same object as was passed instead of a new one", HvNAME (SvSTASH (sv)));
+            croak ("%s::FREEZE method returned same object as was passed instead of a new one", HvNAME (SvSTASH (sv)));
 
           encode_ch (enc, '(');
           encode_ch (enc, '"');
@@ -740,15 +753,14 @@
 
           encode_ch (enc, ']');
 
-          PUTBACK;
-
           FREETMPS; LEAVE;
         }
       else if ((enc->json.flags & F_CONV_BLESSED) && (method = gv_fetchmethod_autoload (stash, "TO_JSON", 0)))
         {
           dSP;
 
-          ENTER; SAVETMPS; PUSHMARK (SP);
+          ENTER; SAVETMPS;
+          PUSHMARK (SP);
           // we re-bless the reference to get overload and other niceties right
           XPUSHs (sv_bless (sv_2mortal (newRV_inc (sv)), stash));
 
@@ -873,12 +885,20 @@
            SvPV_nolen (sv), (unsigned int)SvFLAGS (sv));
 }
 
+static int
+json_scalar (SV *scalar)
+{
+  return 0;//D
+  if (!SvROK (scalar))
+    return 1;
+}
+
 static SV *
 encode_json (SV *scalar, JSON *json)
 {
   enc_t enc;
 
-  if (!(json->flags & F_ALLOW_NONREF) && !SvROK (scalar))
+  if (!(json->flags & F_ALLOW_NONREF) && json_scalar (scalar))
     croak ("hash- or arrayref expected (not a simple scalar, use allow_nonref to allow this)");
 
   enc.json      = *json;
@@ -1095,6 +1115,8 @@
 
               utf8 = 1;
             }
+          else if (ch == '\t' && dec->json.flags & F_RELAXED)
+            *cur++ = ch;
           else
             {
               --dec_cur;
@@ -1426,7 +1448,7 @@
           he = hv_iternext (hv);
           hv_iterinit (hv);
 
-          // the next line creates a mortal sv each time its called.
+          // the next line creates a mortal sv each time it's called.
           // might want to optimise this for common cases.
           cb = hv_fetch_ent (dec->json.cb_sk_object, hv_iterkeysv (he), 0, 0);
 
@@ -1435,7 +1457,9 @@
               dSP;
               int count;
 
-              ENTER; SAVETMPS; PUSHMARK (SP);
+              ENTER; SAVETMPS;
+              SAVESTACK_POS ();
+              PUSHMARK (SP);
               XPUSHs (HeVAL (he));
               sv_2mortal (sv);
 
@@ -1458,7 +1482,9 @@
           dSP;
           int count;
 
-          ENTER; SAVETMPS; PUSHMARK (SP);
+          ENTER; SAVETMPS;
+          SAVESTACK_POS ();
+          PUSHMARK (SP);
           XPUSHs (sv_2mortal (sv));
 
           PUTBACK; count = call_sv (dec->json.cb_object, G_ARRAY); SPAGAIN;
@@ -1535,7 +1561,8 @@
     
     dSP;
 
-    ENTER; SAVETMPS; PUSHMARK (SP);
+    ENTER; SAVETMPS;
+    PUSHMARK (SP);
     EXTEND (SP, len + 2);
     // we re-bless the reference to get overload and other niceties right
     PUSHs (tag);