merges r22611 from trunk into ruby_1_9_1.

--
* string.c (rb_str_force_encoding): should clear coderange at changing
  encoding.  [ruby-core:22437]

git-svn-id: http://svn.ruby-lang.org/repos/ruby/branches/ruby_1_9_1@22745 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 1 insertions, 0 deletions

diff --git a/string.c b/string.c
index 35991bb7e..11aaa3eb5 100644
--- a/string.c
+++ b/string.c
@@ -6780,6 +6780,7 @@ rb_str_force_encoding(VALUE str, VALUE enc)
 {
     str_modifiable(str);
     rb_enc_associate(str, rb_to_encoding(enc));
+    ENC_CODERANGE_CLEAR(str);
     return str;
 }