Fix value returned by mysql_warning_count() after fetching a prepared

statement that generated a warning. (Bug #15510)


sql-common/client.c:
  Reset warning_count in free_old_query(), don't stomp old value for
  it in cli_read_query_result().
tests/mysql_client_test.c:
  Add new regression test

sql-common/client.c

@@ -715,6 +715,7 @@ void free_old_query(MYSQL *mysql)
   init_alloc_root(&mysql->field_alloc,8192,0); /* Assume rowlength < 8192 */
   mysql->fields= 0;
   mysql->field_count= 0;			/* For API */
+  mysql->warning_count= 0;
   mysql->info= 0;
   DBUG_VOID_RETURN;
 }
@@ -2484,7 +2485,6 @@ static my_bool cli_read_query_result(MYSQL *mysql)
     DBUG_RETURN(1);
   mysql->status= MYSQL_STATUS_GET_RESULT;
   mysql->field_count= (uint) field_count;
-  mysql->warning_count= 0;
   DBUG_PRINT("exit",("ok"));
   DBUG_RETURN(0);
 }

tests/mysql_client_test.c

@@ -14590,6 +14590,40 @@ static void test_bug14845()
   myquery(rc);
 }
 
+
+/*
+  Bug #15510: mysql_warning_count returns 0 after mysql_stmt_fetch which
+  should warn
+*/
+static void test_bug15510()
+{
+  MYSQL_STMT *stmt;
+  MYSQL_RES *res;
+  int rc;
+  const char *query= "select 1 from dual where 1/0";
+
+  myheader("test_bug15510");
+
+  rc= mysql_query(mysql, "set @@sql_mode='ERROR_FOR_DIVISION_BY_ZERO'");
+  myquery(rc);
+
+  stmt= mysql_stmt_init(mysql);
+
+  rc= mysql_stmt_prepare(stmt, query, strlen(query));
+  check_execute(stmt, rc);
+
+  rc= mysql_stmt_execute(stmt);
+  check_execute(stmt, rc);
+
+  rc= mysql_stmt_fetch(stmt);
+  DIE_UNLESS(mysql_warning_count(mysql));
+
+  /* Cleanup */
+  mysql_stmt_close(stmt);
+  rc= mysql_query(mysql, "set @@sql_mode=''");
+  myquery(rc);
+}
+
 /*
   Read and parse arguments and MySQL options from my.cnf
 */
@@ -14849,6 +14883,7 @@ static struct my_tests_st my_tests[]= {
   { "test_bug13488", test_bug13488 },
   { "test_bug13524", test_bug13524 },
   { "test_bug14845", test_bug14845 },
+  { "test_bug15510", test_bug15510},
   { 0, 0 }
 };