Index: awk.h
===================================================================
RCS file: /cvsroot/xmlgawk/xmlgawk/awk.h,v
retrieving revision 1.30
diff -b -u -p -r1.30 awk.h
--- awk.h	14 Mar 2006 21:59:28 -0000	1.30
+++ awk.h	11 Jul 2006 14:56:49 -0000
@@ -1217,8 +1217,12 @@ extern int parse_escape P((const char **
 #ifdef MBS_SUPPORT
 extern NODE *str2wstr P((NODE *n, size_t **ptr));
 #define force_wstring(n)	str2wstr(n, NULL)
+extern void release_wstr P((NODE *n));
+#define RELEASE_WSTR(N) release_wstr(N);
 extern const wchar_t *wstrstr P((const wchar_t *haystack, size_t hs_len, const wchar_t *needle, size_t needle_len));
 extern const wchar_t *wcasestrstr P((const wchar_t *haystack, size_t hs_len, const wchar_t *needle, size_t needle_len));
+#else /* !MBS_SUPPORT */
+#define RELEASE_WSTR(N)  /* no-op */
 #endif
 /* re.c */
 extern Regexp *make_regexp P((const char *s, size_t len, int ignorecase, int dfa));
Index: node.c
===================================================================
RCS file: /cvsroot/xmlgawk/xmlgawk/node.c,v
retrieving revision 1.4
diff -b -u -p -r1.4 node.c
--- node.c	6 Mar 2006 22:37:19 -0000	1.4
+++ node.c	11 Jul 2006 14:56:49 -0000
@@ -214,15 +214,7 @@ format_val(const char *format, int index
 no_malloc:
 	s->stref = 1;
 	s->flags |= STRCUR;
-#if defined MBS_SUPPORT
-	if ((s->flags & WSTRCUR) != 0) {
-		assert(s->wstptr != NULL);
-		free(s->wstptr);
-		s->wstptr = NULL;
-		s->wstlen = 0;
-		s->flags &= ~WSTRCUR;
-	}
-#endif
+	RELEASE_WSTR(s)
 	return s;
 }
 
@@ -508,20 +500,13 @@ unref(register NODE *tmp)
 				return;
 			}
 			free(tmp->stptr);
-#if defined MBS_SUPPORT
-			if (tmp->wstptr != NULL) {
-				assert((tmp->flags & WSTRCUR) != 0);
-				free(tmp->wstptr);
-			}
-			tmp->flags &= ~WSTRCUR;
-			tmp->wstptr = NULL;
-			tmp->wstlen = 0;
-#endif
+			RELEASE_WSTR(tmp)
 		}
 		freenode(tmp);
 		return;
 	}
 	if ((tmp->flags & FIELD) != 0) {
+		RELEASE_WSTR(tmp)
 		freenode(tmp);
 		return;
 	}
@@ -685,6 +670,28 @@ isnondecimal(const char *str, int use_lo
 }
 
 #if defined MBS_SUPPORT
+
+void
+release_wstr(NODE *n)
+{
+	if ((n->flags & WSTRCUR) != 0) {
+		assert(n->wstptr != NULL);
+		free(n->wstptr);
+		n->wstptr = NULL;
+		n->wstlen = 0;
+		n->flags &= ~WSTRCUR;
+	}
+#if 0
+	/* I suspect this is generally not safe (to check wstptr or wstlen
+	   fields if the WSTRCUR is not set), so it's commented out.
+	   Would it be valid to check these if the STRCUR flag is set? */
+	else if ((n->flags & STRCUR) != 0) {
+		assert(n->wstptr == NULL);
+		assert(n->wstlen == 0);
+	}
+#endif
+}
+
 /* str2wstr --- convert a multibyte string to a wide string */
 
 NODE *
@@ -702,12 +709,11 @@ str2wstr(NODE *n, size_t **ptr)
 			return n;
 		/* otherwise
 			fall through and recompute to fill in the array */
-	}
 
-	if (n->wstptr != NULL) {
+		assert(n->wstptr != NULL);
 		free(n->wstptr);
-		n->wstptr = NULL;
-		n->wstlen = 0;
+		/* no need to reset wstptr and wstlen since they will
+		   be set below */
 	}
 
 	/*
Index: builtin.c
===================================================================
RCS file: /cvsroot/xmlgawk/xmlgawk/builtin.c,v
retrieving revision 1.9
diff -b -u -p -r1.9 builtin.c
--- builtin.c	8 Mar 2006 23:39:59 -0000	1.9
+++ builtin.c	11 Jul 2006 14:56:49 -0000
@@ -2527,6 +2527,7 @@ sub_common(NODE *tree, long how_many, in
 	free(t->stptr);
 	t->stptr = buf;
 	t->stlen = textlen;
+	RELEASE_WSTR(t)
 
 	free_temp(s);
 	if (matches > 0 && lhs) {
Index: eval.c
===================================================================
RCS file: /cvsroot/xmlgawk/xmlgawk/eval.c,v
retrieving revision 1.17
diff -b -u -p -r1.17 eval.c
--- eval.c	6 Jul 2006 19:10:38 -0000	1.17
+++ eval.c	11 Jul 2006 14:56:50 -0000
@@ -1176,6 +1176,7 @@ r_tree_eval(register NODE *tree, int isc
 			memcpy(l->stptr + l->stlen, r->stptr, r->stlen);
 			l->stlen += r->stlen;
 			l->stptr[l->stlen] = '\0';
+			RELEASE_WSTR(l)
 		} else {
 			char *nval;
 			size_t nlen = l->stlen + r->stlen + 2;