Bug #6043 erratic searching for diacriticals in indexed MyISAM UTF-8 table

mysql-test/r/ctype_utf8.result

@@ -750,3 +750,32 @@ SELECT id FROM t1 WHERE (list_id = 1) AND (term = "letterd");
 id
 4
 DROP TABLE t1;
+SET NAMES latin1;
+CREATE TABLE t1 (
+id int unsigned NOT NULL auto_increment,
+list_id smallint unsigned NOT NULL,
+term text NOT NULL,
+PRIMARY KEY(id),
+INDEX(list_id, term(19))
+) TYPE=MyISAM CHARSET=utf8;
+Warnings:
+Warning	1287	'TYPE=storage_engine' is deprecated; use 'ENGINE=storage_engine' instead
+INSERT INTO t1 set list_id = 1, term = "testtest";
+INSERT INTO t1 set list_id = 1, term = "testetest";
+INSERT INTO t1 set list_id = 1, term = "testtest";
+SELECT id, term FROM t1 where (list_id = 1) AND (term = "testtest");
+id	term
+1	testtest
+2	testetest
+3	testtest
+SELECT id, term FROM t1 where (list_id = 1) AND (term = "testetest");
+id	term
+1	testtest
+2	testetest
+3	testtest
+SELECT id, term FROM t1 where (list_id = 1) AND (term = "testtest");
+id	term
+1	testtest
+2	testetest
+3	testtest
+DROP TABLE t1;

mysql-test/t/ctype_utf8.test

@@ -592,3 +592,23 @@ SELECT id FROM t1 WHERE (list_id = 1) AND (term = "letterb");
 SELECT id FROM t1 WHERE (list_id = 1) AND (term = "lettera");
 SELECT id FROM t1 WHERE (list_id = 1) AND (term = "letterd");
 DROP TABLE t1;
+
+
+#
+# Bug #6043 erratic searching for diacriticals in indexed MyISAM UTF-8 table
+#
+SET NAMES latin1;
+CREATE TABLE t1 (
+    id int unsigned NOT NULL auto_increment,
+    list_id smallint unsigned NOT NULL,
+    term text NOT NULL,
+    PRIMARY KEY(id),
+    INDEX(list_id, term(19))
+) TYPE=MyISAM CHARSET=utf8;
+INSERT INTO t1 set list_id = 1, term = "testtest";
+INSERT INTO t1 set list_id = 1, term = "testetest";
+INSERT INTO t1 set list_id = 1, term = "testtest";
+SELECT id, term FROM t1 where (list_id = 1) AND (term = "testtest");
+SELECT id, term FROM t1 where (list_id = 1) AND (term = "testetest");
+SELECT id, term FROM t1 where (list_id = 1) AND (term = "testtest");
+DROP TABLE t1;

sql/field.cc

@@ -5000,10 +5000,10 @@ String *Field_blob::val_str(String *val_buffer __attribute__((unused)),
 int Field_blob::cmp(const char *a,uint32 a_length, const char *b,
 		    uint32 b_length)
 {
-  int diff=my_strnncoll(field_charset,
-			(const uchar*)a,min(a_length,b_length),
-			(const uchar*)b,min(a_length,b_length));
-  return diff ? diff : (int) (a_length - b_length);
+  return field_charset->coll->strnncoll(field_charset, 
+                                        (const uchar*)a, a_length,
+                                        (const uchar*)b, b_length,
+                                        0);
 }
 
 
@@ -5087,8 +5087,8 @@ void Field_blob::get_key_image(char *buff,uint length,
 
   get_ptr(&blob);
   uint char_length= length / cs->mbmaxlen;
-  char_length= my_charpos(cs, blob, blob + length, char_length);
-  set_if_smaller(length, char_length);
+  char_length= my_charpos(cs, blob, blob + blob_length, char_length);
+  set_if_smaller(blob_length, char_length);
 
   if ((uint32) length > blob_length)
   {