diff --git a/qse/cmd/awk/awk.c b/qse/cmd/awk/awk.c
index 201c145e..57c519fc 100644
--- a/qse/cmd/awk/awk.c
+++ b/qse/cmd/awk/awk.c
@@ -206,7 +206,7 @@ static qse_htb_walk_t print_awk_value (
 		else
 		{
 			dprint (QSE_T("***OUT OF MEMORY***\n"));
-		}	
+		}
 	}
 	else
 	{
diff --git a/qse/include/qse/awk/awk.h b/qse/include/qse/awk/awk.h
index edaae3a4..361340cf 100644
--- a/qse/include/qse/awk/awk.h
+++ b/qse/include/qse/awk/awk.h
@@ -1681,6 +1681,14 @@ QSE_EXPORT void qse_awk_seterrnum (
 	                           *   an error message */
 );
 
+QSE_EXPORT void qse_awk_seterrfmt (
+	qse_awk_t*              awk,
+	qse_awk_errnum_t        errnum,
+	qse_awk_loc_t*          errloc,
+	const qse_char_t*       msgfmt,
+	...
+);
+
 /**
  * The qse_awk_seterrinf() function sets the error information. This function
  * may be useful if you want to set a custom error message rather than letting
@@ -1691,6 +1699,7 @@ QSE_EXPORT void qse_awk_seterrinf (
 	const qse_awk_errinf_t* errinf /**< error information */
 );
 
+
 /**
  * The qse_awk_geterror() function gets error information via parameters.
  */
@@ -2367,6 +2376,14 @@ QSE_EXPORT void qse_awk_rtx_seterrinf (
 	const qse_awk_errinf_t* errinf /**< error information */
 );
 
+QSE_EXPORT void qse_awk_rtx_seterrfmt (
+	qse_awk_rtx_t*       rtx,
+	qse_awk_errnum_t     errnum,
+	const qse_awk_loc_t* errloc,
+	const qse_char_t*    errfmt,
+	...
+);
+
 /**
  * The qse_awk_rtx_seterror() function sets error information.
  */
diff --git a/qse/lib/awk/Awk.cpp b/qse/lib/awk/Awk.cpp
index ea4cd2c0..c9e804c8 100644
--- a/qse/lib/awk/Awk.cpp
+++ b/qse/lib/awk/Awk.cpp
@@ -652,7 +652,7 @@ int Awk::Value::setIndexedVal (Run* r, const Index& idx, val_t* v)
 {
 	QSE_ASSERT (r != QSE_NULL);
 
-	if (QSE_AWK_RTX_GETVALTYPE (r->rtx, val) != QSE_AWK_VAL_MAP)
+	if (QSE_AWK_RTX_GETVALTYPE (r->rtx, this->val) != QSE_AWK_VAL_MAP)
 	{
 		// the previous value is not a map. 
 		// a new map value needs to be created first.
@@ -666,8 +666,7 @@ int Awk::Value::setIndexedVal (Run* r, const Index& idx, val_t* v)
 		qse_awk_rtx_refupval (r->rtx, map);
 
 		// update the map with a given value 
-		if (qse_awk_rtx_setmapvalfld (
-			r->rtx, map, idx.ptr, idx.len, v) == QSE_NULL)
+		if (qse_awk_rtx_setmapvalfld(r->rtx, map, idx.ptr, idx.len, v) == QSE_NULL)
 		{
 			qse_awk_rtx_refdownval (r->rtx, map);
 			r->awk->retrieveError (r);
@@ -678,7 +677,7 @@ int Awk::Value::setIndexedVal (Run* r, const Index& idx, val_t* v)
 		if (this->run) 
 		{
 			// if val is not nil, this->run can't be NULL
-			qse_awk_rtx_refdownval (this->run->rtx, val);
+			qse_awk_rtx_refdownval (this->run->rtx, this->val);
 		}
 
 		this->run = r;
@@ -700,8 +699,7 @@ int Awk::Value::setIndexedVal (Run* r, const Index& idx, val_t* v)
 		}
 
 		// update the map with a given value 
-		if (qse_awk_rtx_setmapvalfld (
-			r->rtx, val, idx.ptr, idx.len, v) == QSE_NULL)
+		if (qse_awk_rtx_setmapvalfld(r->rtx, val, idx.ptr, idx.len, v) == QSE_NULL)
 		{
 			r->awk->retrieveError (r);
 			return -1;
diff --git a/qse/lib/awk/err.c b/qse/lib/awk/err.c
index 217f535b..32dce9f5 100644
--- a/qse/lib/awk/err.c
+++ b/qse/lib/awk/err.c
@@ -207,22 +207,21 @@ void qse_awk_geterrinf (const qse_awk_t* awk, qse_awk_errinf_t* errinf)
 	}
 }
 
-void qse_awk_geterror (
-	const qse_awk_t* awk, qse_awk_errnum_t* errnum, 
-	const qse_char_t** errmsg, qse_awk_loc_t* errloc)
+void qse_awk_geterror (const qse_awk_t* awk, qse_awk_errnum_t* errnum, const qse_char_t** errmsg, qse_awk_loc_t* errloc)
 {
-	if (errnum != QSE_NULL) *errnum = awk->errinf.num;
-	if (errmsg != QSE_NULL) 
+	if (errnum) *errnum = awk->errinf.num;
+	if (errmsg) 
 	{
 		*errmsg = (awk->errinf.msg[0] == QSE_T('\0'))?
 			qse_awk_geterrstr(awk)(awk,awk->errinf.num):
 			awk->errinf.msg;
 	}
-	if (errloc != QSE_NULL) *errloc = awk->errinf.loc;
+	if (errloc) *errloc = awk->errinf.loc;
 }
 
-void qse_awk_seterrnum (
-	qse_awk_t* awk, qse_awk_errnum_t errnum, const qse_cstr_t* errarg)
+
+
+void qse_awk_seterrnum (qse_awk_t* awk, qse_awk_errnum_t errnum, const qse_cstr_t* errarg)
 {
 	qse_awk_seterror (awk, errnum, errarg, QSE_NULL);
 }
@@ -232,9 +231,21 @@ void qse_awk_seterrinf (qse_awk_t* awk, const qse_awk_errinf_t* errinf)
 	QSE_MEMCPY (&awk->errinf, errinf, QSE_SIZEOF(*errinf));
 }
 
-void qse_awk_seterror (
-	qse_awk_t* awk, qse_awk_errnum_t errnum, const qse_cstr_t* errarg,
-	const qse_awk_loc_t* errloc)
+void qse_awk_seterrfmt (qse_awk_t* awk, qse_awk_errnum_t errnum, qse_awk_loc_t* errloc, const qse_char_t* errfmt, ...)
+{
+	va_list ap;
+
+	QSE_MEMSET (&awk->errinf, 0, QSE_SIZEOF(awk->errinf));
+	awk->errinf.num = errnum;
+
+	va_start (ap, errfmt);
+	qse_strxvfmt (awk->errinf.msg, QSE_COUNTOF(awk->errinf.msg), errfmt, ap);
+	va_end (ap);
+
+	if (errloc) awk->errinf.loc = *errloc;
+}
+
+void qse_awk_seterror (qse_awk_t* awk, qse_awk_errnum_t errnum, const qse_cstr_t* errarg,	const qse_awk_loc_t* errloc)
 {
 	const qse_char_t* errfmt;
 
@@ -243,14 +254,12 @@ void qse_awk_seterror (
 
 	errfmt = qse_awk_geterrstr(awk)(awk,errnum);
 	QSE_ASSERT (errfmt != QSE_NULL);
-	qse_strxfncpy (
-		awk->errinf.msg, QSE_COUNTOF(awk->errinf.msg),
-		errfmt, errarg
-	);
+	qse_strxfncpy (awk->errinf.msg, QSE_COUNTOF(awk->errinf.msg), errfmt, errarg);
 
 	if (errloc != QSE_NULL) awk->errinf.loc = *errloc;
 }
 
+
 qse_awk_errnum_t qse_awk_rtx_geterrnum (const qse_awk_rtx_t* rtx)
 {
 	return rtx->errinf.num;
@@ -301,9 +310,22 @@ void qse_awk_rtx_seterrinf (qse_awk_rtx_t* rtx, const qse_awk_errinf_t* errinf)
 	QSE_MEMCPY (&rtx->errinf, errinf, QSE_SIZEOF(*errinf));
 }
 
-void qse_awk_rtx_seterror (
-	qse_awk_rtx_t* rtx, qse_awk_errnum_t errnum, const qse_cstr_t* errarg,
-	const qse_awk_loc_t* errloc)
+void qse_awk_rtx_seterrfmt (qse_awk_rtx_t* rtx, qse_awk_errnum_t errnum, const qse_awk_loc_t* errloc, const qse_char_t* errfmt, ...)
+{
+	va_list ap;
+
+	QSE_MEMSET (&rtx->errinf, 0, QSE_SIZEOF(rtx->errinf));
+	rtx->errinf.num = errnum;
+
+	va_start (ap, errfmt);
+	qse_strxvfmt (rtx->errinf.msg, QSE_COUNTOF(rtx->errinf.msg), errfmt, ap);
+	va_end (ap);
+
+	if (errloc) rtx->errinf.loc = *errloc;
+}
+
+
+void qse_awk_rtx_seterror (qse_awk_rtx_t* rtx, qse_awk_errnum_t errnum, const qse_cstr_t* errarg, const qse_awk_loc_t* errloc)
 {
 	const qse_char_t* errfmt;
 
diff --git a/qse/lib/awk/fnc.c b/qse/lib/awk/fnc.c
index 8b98c97c..4f00929b 100644
--- a/qse/lib/awk/fnc.c
+++ b/qse/lib/awk/fnc.c
@@ -1562,7 +1562,7 @@ static QSE_INLINE int __fnc_asort (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t*
 	qse_size_t nargs;
 	qse_awk_val_t* a0, * a0_val, * a1, * a2;
 	qse_awk_val_type_t a0_type, v_type;
-	qse_awk_val_t* r, * rmap;
+	qse_awk_val_t* r, * rmap = QSE_NULL;
 	qse_awk_int_t rv = 0; /* as if no element in the map */
 	qse_awk_val_map_itr_t itr;
 	qse_awk_fun_t* fun = QSE_NULL;
@@ -1585,7 +1585,7 @@ static QSE_INLINE int __fnc_asort (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t*
 			goto done;
 		}
 
-		qse_awk_rtx_seterrnum (rtx, QSE_AWK_ENOTMAP, QSE_NULL);
+		qse_awk_rtx_seterrfmt (rtx, QSE_AWK_ENOTMAP, QSE_NULL, QSE_T("source not a map"));
 		return -1;
 	}
 
@@ -1601,7 +1601,7 @@ static QSE_INLINE int __fnc_asort (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t*
 			a2 = qse_awk_rtx_getarg(rtx, 2);
 			if (QSE_AWK_RTX_GETVALTYPE(rtx, a2) != QSE_AWK_VAL_FUN)
 			{
-				qse_awk_rtx_seterrnum (rtx, QSE_AWK_EINVAL, QSE_NULL);
+				qse_awk_rtx_seterrfmt (rtx, QSE_AWK_EINVAL, QSE_NULL, QSE_T("comparator not a function"));
 				return -1;
 			}
 
@@ -1609,7 +1609,7 @@ static QSE_INLINE int __fnc_asort (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t*
 			if (fun->nargs < 2) 
 			{
 				/* the comparison accepts less than 2 arguments */
-				qse_awk_rtx_seterrnum (rtx, QSE_AWK_EINVAL, QSE_NULL);
+				qse_awk_rtx_seterrfmt (rtx, QSE_AWK_EINVAL, QSE_NULL, QSE_T("%.*s not accepting 2 arguments"), (int)fun->name.len, fun->name.ptr);
 				return -1;
 			}
 		}
@@ -1638,11 +1638,12 @@ static QSE_INLINE int __fnc_asort (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t*
 				while (i > 0)
 				{
 					--i;
-					qse_awk_rtx_freeval (rtx, va[i], 0);
+					qse_awk_rtx_refdownval (rtx, va[i]);
 				}
 				qse_awk_rtx_freemem (rtx, va);
 				return -1;
 			}
+			qse_awk_rtx_refupval (rtx, va[i]);
 			i++;
 		}
 		while (qse_awk_rtx_getnextmapvalitr(rtx, a0_val, &itr));
@@ -1651,7 +1652,9 @@ static QSE_INLINE int __fnc_asort (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t*
 	{
 		do
 		{
-			va[i++] = (qse_awk_val_t*)QSE_AWK_VAL_MAP_ITR_VAL(&itr);
+			va[i] = (qse_awk_val_t*)QSE_AWK_VAL_MAP_ITR_VAL(&itr);
+			qse_awk_rtx_refupval (rtx, va[i]);
+			i++;
 		}
 		while (qse_awk_rtx_getnextmapvalitr(rtx, a0_val, &itr));
 	}
@@ -1670,17 +1673,14 @@ static QSE_INLINE int __fnc_asort (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t*
 
 	if (x <= -1 || !(rmap = qse_awk_rtx_makemapval(rtx)))
 	{
-		if (sort_keys)
-		{
-			for (i = 0; i < msz; i++) qse_awk_rtx_freeval (rtx, va[i], 0);
-		}
+		for (i = 0; i < msz; i++) qse_awk_rtx_refdownval (rtx, va[i]);
 		qse_awk_rtx_freemem (rtx, va);
 		return -1;
 	}
 
 	for (i = 0; i < msz; i++)
 	{
-		qse_char_t ridx[128];
+		qse_char_t ridx[128]; /* TODO: make it dynamic? can overflow? */
 		qse_size_t ridx_len;
 
 		ridx_len = qse_fmtuintmax (
@@ -1695,32 +1695,42 @@ static QSE_INLINE int __fnc_asort (qse_awk_rtx_t* rtx, const qse_awk_fnc_info_t*
 
 		if (qse_awk_rtx_setmapvalfld(rtx, rmap, ridx, ridx_len, va[i]) == QSE_NULL)
 		{
-			qse_awk_rtx_freeval (rtx, rmap, 0); /* this delete the elements added. */
-			if (sort_keys)
+			/* decrement the reference count of the values not added to the map */
+			do
 			{
-				/* delete the elements not added yet */
-				do
-				{
-					qse_awk_rtx_freeval(rtx, va[i], 0);
-					i++;
-				}
-				while (i < msz);
+				qse_awk_rtx_refdownval (rtx, va[i]);
+				i++;
 			}
+			while (i < msz);
+			qse_awk_rtx_freeval (rtx, rmap, 0); /* this derefs the elements added. */
 			qse_awk_rtx_freemem (rtx, va);
 			return -1;
 		}
+
+		qse_awk_rtx_refdownval (rtx, va[i]); /* deref it as it has been added to the map */
 	}
 
 	rv = msz;
 	qse_awk_rtx_freemem (rtx, va);
 
-	qse_awk_rtx_refupval (rtx, rmap);
-	x = qse_awk_rtx_setrefval (rtx, (qse_awk_val_ref_t*)a1, rmap);
-	qse_awk_rtx_refdownval (rtx, rmap);
-	if (x <= -1) return -1;
-
 done:
 	r = qse_awk_rtx_makeintval(rtx, rv);
+	if (!r) return -1;
+
+	if (rmap)
+	{
+		/* rmap can be NULL when a jump has been made for an empty source 
+		 * at the beginning of this fucntion */
+		qse_awk_rtx_refupval (rtx, rmap);
+		x = qse_awk_rtx_setrefval (rtx, (qse_awk_val_ref_t*)a1, rmap);
+		qse_awk_rtx_refdownval (rtx, rmap);
+		if (x <= -1) 
+		{
+			qse_awk_rtx_freeval (rtx, r, 0);
+			return -1;
+		}
+	}
+
 	qse_awk_rtx_setretval (rtx, r);
 	return 0;
 }
diff --git a/qse/lib/awk/run.c b/qse/lib/awk/run.c
index ec51a78f..d059c9b1 100644
--- a/qse/lib/awk/run.c
+++ b/qse/lib/awk/run.c
@@ -1197,10 +1197,8 @@ static void fini_rtx (qse_awk_rtx_t* rtx, int fini_globals)
 		{
 			while (rtx->scache_count[i] > 0)
 			{
-				qse_awk_val_str_t* t = 
-					rtx->scache[i][--rtx->scache_count[i]];
-				qse_awk_rtx_freeval (
-					rtx, (qse_awk_val_t*)t, 0);
+				qse_awk_val_str_t* t = rtx->scache[i][--rtx->scache_count[i]];
+				qse_awk_rtx_freeval (rtx, (qse_awk_val_t*)t, 0);
 			}
 		}
 	}