merges r31310 from trunk into ruby_1_9_2.

--
* string.c (rb_str_each_line): check string's length when compare
  separator and string. [ruby-core:35815] fixes #4586

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_1_9_2@31809 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 2 insertions, 1 deletions

diff --git a/string.c b/string.c
index aa3029adbd..6f9fde11ce 100644
--- a/string.c
+++ b/string.c
@@ -5828,7 +5828,8 @@ rb_str_each_line(int argc, VALUE *argv, VALUE str)
 	    p -= n;
 	}
 	if (c == newline &&
-	    (rslen <= 1 || memcmp(RSTRING_PTR(rs), p, rslen) == 0)) {
+	    (rslen <= 1 ||
+	     (pend - p >= rslen && memcmp(RSTRING_PTR(rs), p, rslen) == 0))) {
 	    line = rb_str_new5(str, s, p - s + (rslen ? rslen : n));
 	    OBJ_INFECT(line, str);
 	    rb_enc_cr_str_copy_for_substr(line, str);