3 files changed, 8 insertions, 1 deletions
diff --git a/ChangeLog b/ChangeLog
index 1f136ee90a..d7e5512891 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+Tue Jan 12 21:56:00 2010  Tanaka Akira  <akr@fsij.org>
+
+	* string.c (rb_str_set_len): call rb_str_modify.
+
+	* file.c (realpath_rec): don't call rb_str_modify before
+	  rb_str_set_len.
+
 Tue Jan 12 20:44:14 2010  Tanaka Akira  <akr@fsij.org>
 
 	* file.c (realpath_internal): call rb_secure.
diff --git a/file.c b/file.c
index 99435829c9..1982452ed9 100644
--- a/file.c
+++ b/file.c
@@ -3098,7 +3098,6 @@ realpath_rec(long *prefixlenp, VALUE *resolvedp, char *unresolved, VALUE loopche
             if (*prefixlenp < RSTRING_LEN(*resolvedp)) {
                 char *resolved_names = RSTRING_PTR(*resolvedp) + *prefixlenp;
                 long len = rb_path_last_separator(resolved_names) - resolved_names;
-                rb_str_modify(*resolvedp);
                 rb_str_set_len(*resolvedp, *prefixlenp + len);
             }
         }
diff --git a/string.c b/string.c
index 78620b8048..29e84e3ffe 100644
--- a/string.c
+++ b/string.c
@@ -1667,6 +1667,7 @@ rb_str_unlocktmp(VALUE str)
 void
 rb_str_set_len(VALUE str, long len)
 {
+    rb_str_modify(str);
     STR_SET_LEN(str, len);
     RSTRING_PTR(str)[len] = '\0';
 }