diff --git a/avocado/utils/gdb.py b/avocado/utils/gdb.py
index 09b4b142740b2b59c8734b9d024f6e0e143899b6..52d30d3c4ce4387ca8fdd25b421002abbf24a63a 100644
--- a/avocado/utils/gdb.py
+++ b/avocado/utils/gdb.py
@@ -427,7 +427,7 @@ class GDB(object):
 
         self.send_gdb_command(command)
         responses = self.read_until_break()
-        result_response = None
+        result_response_received = False
 
         for line in responses:
             # If the line can not be properly parsed, it is *most likely*
@@ -442,10 +442,11 @@ class GDB(object):
                     parsed_response.record_type == 'stream'):
                 cmd.stream_messages.append(parsed_response)
             elif parsed_response.type == 'result':
-                if result_response is not None:
+                if result_response_received:
                     # raise an exception here, because no two result
                     # responses should come from a single command AFAIK
                     raise Exception("Many result responses to a single cmd")
+                result_response_received = True
                 cmd.result = parsed_response
             else:
                 self.async_messages.append(parsed_response)
diff --git a/avocado/utils/iso9660.py b/avocado/utils/iso9660.py
index 2bbf55ee720ce6563006dd5a094a979f67c2c90b..382e0500c2da4d0afeccafb14cbb28745ce55656 100644
--- a/avocado/utils/iso9660.py
+++ b/avocado/utils/iso9660.py
@@ -34,7 +34,6 @@ import sys
 import tempfile
 
 from . import process
-from . import path as utils_path
 
 
 try:
@@ -130,7 +129,6 @@ class BaseIso9660(object):
     """
 
     def __init__(self, path):
-        utils_path.check_readable(path)
         self.path = path
 
     def read(self, path):
@@ -382,7 +380,7 @@ class ISO9660PyCDLib(MixInMntDirMount, BaseIso9660):
     def __init__(self, path):
         if not has_pycdlib():
             raise RuntimeError('This class requires the pycdlib library')
-        self.path = path
+        super(ISO9660PyCDLib, self).__init__(path)
         self._iso = None
         self._iso_opened_for_create = False
 
diff --git a/avocado/utils/process.py b/avocado/utils/process.py
index 049efa1310aba9b2508f8d38200b557ad316195a..20d54f41054da403c74a436bb7715067743cc925 100644
--- a/avocado/utils/process.py
+++ b/avocado/utils/process.py
@@ -1149,11 +1149,10 @@ class GDBSubProcess(object):
 
                 elif gdb.is_break_hit(parsed_msg):
                     # waits on fifo read() until end of debug session is notified
-                    r = self.handle_break_hit(parsed_msg)
-                    if r == 'C':
+                    if self.handle_break_hit(parsed_msg) == 'C':
                         self.gdb.connect(self.gdb_server.port)
                         if self._is_thread_stopped():
-                            r = self.gdb.cli_cmd("continue")
+                            self.gdb.cli_cmd("continue")
                         else:
                             log.warn('Binary "%s" terminated inside the '
                                      'debugger before avocado was resumed. '
@@ -1169,7 +1168,7 @@ class GDBSubProcess(object):
 
                 elif gdb.is_fatal_signal(parsed_msg):
                     # waits on fifo read() until end of debug session is notified
-                    r = self.handle_fatal_signal(parsed_msg)
+                    self.handle_fatal_signal(parsed_msg)
                     log.warn('Because "%s" received a fatal signal, this test '
                              'is going to be skipped.', self.binary)
                     # pylint: disable=E0702