diff --git a/src/ecmascript/ecmascript.c b/src/ecmascript/ecmascript.c
index f2babf70..e8a98a0d 100644
--- a/src/ecmascript/ecmascript.c
+++ b/src/ecmascript/ecmascript.c
@@ -246,7 +246,7 @@ ecmascript_get_interpreter(struct view_state *vs)
 		--interpreter_count;
 		return NULL;
 	}
-		
+
 	init_string(&interpreter->code);
 	return interpreter;
 }
@@ -590,8 +590,13 @@ ecmascript_set_timeout(struct ecmascript_interpreter *interpreter, char *code, i
 {
 	assert(interpreter && interpreter->vs->doc_view->document);
 	if (!code) return nullptr;
-	done_string(&interpreter->code);
-	init_string(&interpreter->code);
+	if (interpreter->code.source) {
+		done_string(&interpreter->code);
+	}
+	if (!init_string(&interpreter->code)) {
+		mem_free(code);
+		return nullptr;
+	}
 	add_to_string(&interpreter->code, code);
 	mem_free(code);
 	if (found_in_map_timer(interpreter->vs->doc_view->document->timeout)) {
@@ -607,8 +612,13 @@ timer_id_T
 ecmascript_set_timeout2(struct ecmascript_interpreter *interpreter, JS::HandleValue f, int timeout)
 {
 	assert(interpreter && interpreter->vs->doc_view->document);
-	done_string(&interpreter->code);
-	init_string(&interpreter->code);
+	if (interpreter->code.source) {
+		done_string(&interpreter->code);
+	}
+
+	if (!init_string(&interpreter->code)) {
+		return TIMER_ID_UNDEF;
+	}
 	if (found_in_map_timer(interpreter->vs->doc_view->document->timeout)) {
 		kill_timer(&interpreter->vs->doc_view->document->timeout);
 	}
@@ -625,8 +635,12 @@ timer_id_T
 ecmascript_set_timeout2q(struct ecmascript_interpreter *interpreter, JSValueConst fun, int timeout)
 {
 	assert(interpreter && interpreter->vs->doc_view->document);
-	done_string(&interpreter->code);
-	init_string(&interpreter->code);
+	if (interpreter->code.source) {
+		done_string(&interpreter->code);
+	}
+	if (!init_string(&interpreter->code)) {
+		return TIMER_ID_UNDEF;
+	}
 	if (found_in_map_timer(interpreter->vs->doc_view->document->timeout)) {
 		kill_timer(&interpreter->vs->doc_view->document->timeout);
 	}
@@ -694,7 +708,9 @@ document_parse(struct document *document)
 	}
 
 	struct string str;
-	init_string(&str);
+	if (!init_string(&str)) {
+		return NULL;
+	}
 
 	add_bytes_to_string(&str, f->data, f->length);
 
diff --git a/src/ecmascript/spidermonkey/document.c b/src/ecmascript/spidermonkey/document.c
index 304b9e0c..f73e90b5 100644
--- a/src/ecmascript/spidermonkey/document.c
+++ b/src/ecmascript/spidermonkey/document.c
@@ -1379,7 +1379,9 @@ document_write_do(JSContext *ctx, unsigned int argc, JS::Value *rval, int newlin
 
 	struct string code;
 
-	init_string(&code);
+	if (!init_string(&code)) {
+		return false;
+	}
 
 	if (argc >= 1)
 	{
@@ -1477,8 +1479,13 @@ document_replace(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	struct string needle;
 	struct string heystack;
 
-	init_string(&needle);
-	init_string(&heystack);
+	if (!init_string(&needle)) {
+		return false;
+	}
+	if (!init_string(&heystack)) {
+		done_string(&needle);
+		return false;
+	}
 
 	jshandle_value_to_char_string(&needle, ctx, args[0]);
 	jshandle_value_to_char_string(&heystack, ctx, args[1]);
@@ -1496,23 +1503,27 @@ document_replace(JSContext *ctx, unsigned int argc, JS::Value *vp)
 		fd_len=f->length;
 
 		struct string f_data;
-		init_string(&f_data);
-		add_to_string(&f_data,f->data);
+		if (init_string(&f_data)) {
+			add_to_string(&f_data,f->data);
 
-		struct string nu_str;
-		init_string(&nu_str);
-		string_replace(&nu_str,&f_data,&needle,&heystack);
-		nu_len=nu_str.length;
-		delete_entry_content(cached);
-		/* This is very ugly, indeed. And Yes fd_len isn't 
-		 * logically correct. But using nu_len will cause
-		 * the document to render improperly.
-		 * TBD: somehow better rerender the document 
-		 * now it's places on the session level in doc_loading_callback */
-		int ret = add_fragment(cached,0,nu_str.source,fd_len);
-		normalize_cache_entry(cached,nu_len);
-		document->ecmascript_counter++;
-		//DBG("doc replace %s %s\n", needle.source, heystack.source);
+			struct string nu_str;
+			if (init_string(&nu_str)) {
+				string_replace(&nu_str,&f_data,&needle,&heystack);
+				nu_len=nu_str.length;
+				delete_entry_content(cached);
+				/* This is very ugly, indeed. And Yes fd_len isn't 
+				 * logically correct. But using nu_len will cause
+				 * the document to render improperly.
+				 * TBD: somehow better rerender the document 
+				* now it's places on the session level in doc_loading_callback */
+				int ret = add_fragment(cached,0,nu_str.source,fd_len);
+				normalize_cache_entry(cached,nu_len);
+				document->ecmascript_counter++;
+				done_string(&nu_str);
+			}
+				//DBG("doc replace %s %s\n", needle.source, heystack.source);
+			done_string(&f_data);
+		}
 	}
 
 	done_string(&needle);
@@ -1554,7 +1565,9 @@ document_createComment(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	}
 
 	struct string idstr;
-	init_string(&idstr);
+	if (!init_string(&idstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&idstr, ctx, args[0]);
 	xmlpp::ustring text = idstr.source;
 	done_string(&idstr);
@@ -1648,7 +1661,9 @@ document_createElement(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	}
 
 	struct string idstr;
-	init_string(&idstr);
+	if (!init_string(&idstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&idstr, ctx, args[0]);
 	xmlpp::ustring text = idstr.source;
 	done_string(&idstr);
@@ -1697,7 +1712,9 @@ document_createTextNode(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	}
 
 	struct string idstr;
-	init_string(&idstr);
+	if (!init_string(&idstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&idstr, ctx, args[0]);
 	xmlpp::ustring text = idstr.source;
 	done_string(&idstr);
@@ -1747,7 +1764,9 @@ document_getElementById(JSContext *ctx, unsigned int argc, JS::Value *vp)
 
 	struct string idstr;
 
-	init_string(&idstr);
+	if (!init_string(&idstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&idstr, ctx, args[0]);
 	xmlpp::ustring id = idstr.source;
 
@@ -1809,7 +1828,9 @@ document_getElementsByClassName(JSContext *ctx, unsigned int argc, JS::Value *vp
 
 	struct string idstr;
 
-	init_string(&idstr);
+	if (!init_string(&idstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&idstr, ctx, args[0]);
 	xmlpp::ustring id = idstr.source;
 
@@ -1866,7 +1887,9 @@ document_getElementsByName(JSContext *ctx, unsigned int argc, JS::Value *vp)
 
 	struct string idstr;
 
-	init_string(&idstr);
+	if (!init_string(&idstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&idstr, ctx, args[0]);
 	xmlpp::ustring id = idstr.source;
 
@@ -1924,7 +1947,9 @@ document_getElementsByTagName(JSContext *ctx, unsigned int argc, JS::Value *vp)
 
 	struct string idstr;
 
-	init_string(&idstr);
+	if (!init_string(&idstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&idstr, ctx, args[0]);
 	xmlpp::ustring id = idstr.source;
 	std::transform(id.begin(), id.end(), id.begin(), ::tolower);
@@ -1981,7 +2006,9 @@ document_querySelector(JSContext *ctx, unsigned int argc, JS::Value *vp)
 
 	struct string cssstr;
 
-	init_string(&cssstr);
+	if (!init_string(&cssstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&cssstr, ctx, args[0]);
 	xmlpp::ustring css = cssstr.source;
 
@@ -2048,7 +2075,9 @@ document_querySelectorAll(JSContext *ctx, unsigned int argc, JS::Value *vp)
 
 	struct string cssstr;
 
-	init_string(&cssstr);
+	if (!init_string(&cssstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&cssstr, ctx, args[0]);
 	xmlpp::ustring css = cssstr.source;
 
diff --git a/src/ecmascript/spidermonkey/element.c b/src/ecmascript/spidermonkey/element.c
index 98d1b12f..c3060c7a 100644
--- a/src/ecmascript/spidermonkey/element.c
+++ b/src/ecmascript/spidermonkey/element.c
@@ -1730,7 +1730,9 @@ element_get_property_innerHtml(JSContext *ctx, unsigned int argc, JS::Value *vp)
 		return true;
 	}
 	struct string buf;
-	init_string(&buf);
+	if (!init_string(&buf)) {
+		return false;
+	}
 	walk_tree(&buf, el);
 
 	args.rval().setString(JS_NewStringCopyZ(ctx, buf.source));
@@ -1785,7 +1787,9 @@ element_get_property_outerHtml(JSContext *ctx, unsigned int argc, JS::Value *vp)
 		return true;
 	}
 	struct string buf;
-	init_string(&buf);
+	if (!init_string(&buf)) {
+		return false;
+	}
 	walk_tree(&buf, el, false);
 
 	args.rval().setString(JS_NewStringCopyZ(ctx, buf.source));
@@ -1840,7 +1844,9 @@ element_get_property_textContent(JSContext *ctx, unsigned int argc, JS::Value *v
 	}
 
 	struct string buf;
-	init_string(&buf);
+	if (!init_string(&buf)) {
+		return false;
+	}
 
 	walk_tree_content(&buf, el);
 
@@ -2538,7 +2544,9 @@ element_closest(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	}
 
 	struct string cssstr;
-	init_string(&cssstr);
+	if (!init_string(&cssstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&cssstr, ctx, args[0]);
 	xmlpp::ustring css = cssstr.source;
 	xmlpp::ustring xpath = css2xpath(css);
@@ -2929,8 +2937,13 @@ element_isEqualNode(JSContext *ctx, unsigned int argc, JS::Value *rval)
 	struct string first;
 	struct string second;
 
-	init_string(&first);
-	init_string(&second);
+	if (!init_string(&first)) {
+		return false;
+	}
+	if (!init_string(&second)) {
+		done_string(&first);
+		return false;
+	}
 
 	walk_tree(&first, el, false, true);
 	walk_tree(&second, el2, false, true);
@@ -3014,7 +3027,9 @@ element_matches(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	}
 
 	struct string cssstr;
-	init_string(&cssstr);
+	if (!init_string(&cssstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&cssstr, ctx, args[0]);
 	xmlpp::ustring css = cssstr.source;
 	xmlpp::ustring xpath = css2xpath(css);
@@ -3069,7 +3084,9 @@ element_querySelector(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	}
 
 	struct string cssstr;
-	init_string(&cssstr);
+	if (!init_string(&cssstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&cssstr, ctx, args[0]);
 	xmlpp::ustring css = cssstr.source;
 	xmlpp::ustring xpath = css2xpath(css);
@@ -3131,7 +3148,9 @@ element_querySelectorAll(JSContext *ctx, unsigned int argc, JS::Value *vp)
 
 	struct string cssstr;
 
-	init_string(&cssstr);
+	if (!init_string(&cssstr)) {
+		return false;
+	}
 	jshandle_value_to_char_string(&cssstr, ctx, args[0]);
 	xmlpp::ustring css = cssstr.source;
 	xmlpp::ustring xpath = css2xpath(css);
diff --git a/src/ecmascript/spidermonkey/localstorage.c b/src/ecmascript/spidermonkey/localstorage.c
index be2d68cf..7c655086 100644
--- a/src/ecmascript/spidermonkey/localstorage.c
+++ b/src/ecmascript/spidermonkey/localstorage.c
@@ -246,8 +246,13 @@ localstorage_setitem(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	struct string key;
 	struct string val;
 
-	init_string(&key);
-	init_string(&val);
+	if (!init_string(&key)) {
+		return false;
+	}
+	if (!init_string(&val)) {
+		done_string(&key);
+		return false;
+	}
 
 	JS::Realm *comp = js::GetContextRealm(ctx);
 
diff --git a/src/ecmascript/spidermonkey/location.c b/src/ecmascript/spidermonkey/location.c
index 672657ae..c0995506 100644
--- a/src/ecmascript/spidermonkey/location.c
+++ b/src/ecmascript/spidermonkey/location.c
@@ -152,7 +152,9 @@ location_get_property_hash(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	}
 
 	struct string fragment;
-	init_string(&fragment);
+	if (!init_string(&fragment)) {
+		return false;
+	}
 
 	if (vs->uri->fragmentlen) {
 		add_bytes_to_string(&fragment, vs->uri->fragment, vs->uri->fragmentlen);
@@ -420,7 +422,9 @@ location_get_property_pathname(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	}
 
 	struct string pathname;
-	init_string(&pathname);
+	if (!init_string(&pathname)) {
+		return false;
+	}
 
 	const char *query = memchr(vs->uri->data, '?', vs->uri->datalen);
 	int len = (query ? query - vs->uri->data : vs->uri->datalen);
@@ -469,7 +473,9 @@ location_get_property_port(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	}
 
 	struct string port;
-	init_string(&port);
+	if (!init_string(&port)) {
+		return false;
+	}
 	if (vs->uri->portlen) {
 		add_bytes_to_string(&port, vs->uri->port, vs->uri->portlen);
 	}
@@ -519,7 +525,9 @@ location_get_property_protocol(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	}
 
 	struct string proto;
-	init_string(&proto);
+	if (!init_string(&proto)) {
+		return false;
+	}
 
 	/* Custom or unknown keep the URI untouched. */
 	if (vs->uri->protocol == PROTOCOL_UNKNOWN) {
@@ -575,7 +583,9 @@ location_get_property_search(JSContext *ctx, unsigned int argc, JS::Value *vp)
 	}
 
 	struct string search;
-	init_string(&search);
+	if (!init_string(&search)) {
+		return false;
+	}
 
 	const char *query = memchr(vs->uri->data, '?', vs->uri->datalen);
 
diff --git a/src/ecmascript/spidermonkey/util.h b/src/ecmascript/spidermonkey/util.h
index fd7e599d..12bcb90f 100644
--- a/src/ecmascript/spidermonkey/util.h
+++ b/src/ecmascript/spidermonkey/util.h
@@ -43,7 +43,9 @@ jsval_to_boolean(JSContext *ctx, JS::Value *vp)
 void
 jshandle_value_to_char_string(struct string *string, JSContext *ctx, JS::HandleValue obj)
 {
-	init_string(string);
+	if (!init_string(string)) {
+		return;
+	}
 
 	if (obj.isString())
 	{