diff --git a/ChangeLog b/ChangeLog
index 239b487f1e..a2d7281955 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+Sun Aug  2 21:04:37 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
+
+	* parse.y (literal_concat0): tail can be nil.  [ruby-dev:38980]
+
 Sun Aug  2 20:09:07 2009  Nobuyoshi Nakada  <nobu@ruby-lang.org>
 
 	* array.c (rb_ary_combination, rb_ary_product): prevent from GC.
diff --git a/bootstraptest/test_syntax.rb b/bootstraptest/test_syntax.rb
index 131625ea6b..6843b23285 100644
--- a/bootstraptest/test_syntax.rb
+++ b/bootstraptest/test_syntax.rb
@@ -831,3 +831,8 @@ assert_normal_exit %q{
 assert_equal 'ok', %q{
   "#{}""#{}ok"
 }, '[ruby-dev:38968]'
+
+
+assert_equal 'ok', %q{
+  "o" "#{}k"
+}, '[ruby-dev:38980]'
diff --git a/parse.y b/parse.y
index 80fef61f34..646e0ceeff 100644
--- a/parse.y
+++ b/parse.y
@@ -7782,6 +7782,7 @@ list_concat_gen(struct parser_params *parser, NODE *head, NODE *tail)
 static int
 literal_concat0(struct parser_params *parser, VALUE head, VALUE tail)
 {
+    if (NIL_P(tail)) return 1;
     if (!rb_enc_compatible(head, tail)) {
 	compile_error(PARSER_ARG "string literal encodings differ (%s / %s)",
 		      rb_enc_name(rb_enc_get(head)),