Throw proper SyntaxError if unable to parse a regular expression

.test262/Makefile

@@ -18,7 +18,7 @@ otto: build
 test-otto:
 	$(TEST) $(WITH_otto)
 
-test.otto: otto
+test.otto:
 	$(TEST) $(WITH_otto) | tee $@
 
 test.otto-: 
@@ -36,9 +36,9 @@ test.v8-:
 release: otto gauntlet
 
 clean:
-	rm -f test.otto digest.json
+	rm -f test.otto digest.json .node.tmp.js
 
-digest.json:
+digest.json: test.otto
 	./digest < test.otto > $@
 
 digest.json-:
@@ -69,6 +69,10 @@ try-tmp: tmp.js
 	cat shim.js $< | $(otto)
 	@echo PASS
 
+node-try-tmp: tmp.js
+	cat shim.js $< > .node.tmp.js
+	node ./.node.tmp.js
+
 look: .fail
 	cat $<
 	@echo `readlink $<`

type_regexp.go

@@ -50,8 +50,13 @@ func (runtime *_runtime) newRegExpObject(pattern string, flags string) *_object
 		re2pattern = fmt.Sprintf("(?%s:%s)", re2flags, re2pattern)
 	}
 
+	regularExpression, err := regexp.Compile(re2pattern)
+	if err != nil {
+		panic(newSyntaxError("Invalid regular expression: %s", err.Error()[22:]))
+	}
+
 	self._RegExp = &_regExpObject{
-		RegularExpression: regexp.MustCompile(re2pattern),
+		RegularExpression: regularExpression,
 		Global: global,
 		IgnoreCase: ignoreCase,
 		Multiline: multiline,