diff --git a/swh/indexer/fossology_license.py b/swh/indexer/fossology_license.py
index 04ae709..68efa6c 100644
--- a/swh/indexer/fossology_license.py
+++ b/swh/indexer/fossology_license.py
@@ -1,138 +1,151 @@
 # Copyright (C) 2016-2017  The Software Heritage developers
 # See the AUTHORS file at the top-level directory of this distribution
 # License: GNU General Public License version 3, or any later version
 # See top-level LICENSE file for more information
 
 import click
 import subprocess
 
 from swh.model import hashutil
 
 from .indexer import BaseIndexer, DiskIndexer
 
 
-def compute_license(tool, path):
+def compute_license(tool, path, log=None):
     """Determine license from file at path.
 
     Args:
         path: filepath to determine the license
 
     Returns:
         A dict with the following keys:
         - licenses ([str]): associated detected licenses to path
         - path (bytes): content filepath
         - tool (str): tool used to compute the output
 
     """
-    properties = subprocess.check_output([tool, path],
-                                         universal_newlines=True)
-    if properties:
-        res = properties.rstrip().split(' contains license(s) ')
-        licenses = res[1].split(',')
-
+    try:
+        properties = subprocess.check_output([tool, path],
+                                             universal_newlines=True)
+        if properties:
+            res = properties.rstrip().split(' contains license(s) ')
+            licenses = res[1].split(',')
+
+            return {
+                'licenses': licenses,
+                'path': path,
+            }
+    except subprocess.CalledProcessError:
+        if log:
+            from os import path as __path
+            log.exception('Problem during license detection for sha1 %s' %
+                          __path.basename(path))
         return {
-            'licenses': licenses,
+            'licenses': [],
             'path': path,
         }
 
 
 class ContentFossologyLicenseIndexer(BaseIndexer, DiskIndexer):
     """Indexer in charge of:
     - filtering out content already indexed
     - reading content from objstorage per the content's id (sha1)
     - computing {license, encoding} from that content
     - store result in storage
 
     """
     ADDITIONAL_CONFIG = {
         'workdir': ('str', '/tmp/swh/indexer.fossology.license'),
         'tool': ('dict', {
             'name': 'nomos',
             'version': '3.1.0rc2-31-ga2cbb8c',
             'command': '/usr/bin/nomossa',
         }),
     }
 
     CONFIG_BASE_FILENAME = 'indexer/fossology_license'
 
     def __init__(self):
         super().__init__()
         self.working_directory = self.config['workdir']
         self.tool = self.config['tool']['command']
         self.tool_name = self.config['tool']['name']
         self.tool_version = self.config['tool']['version']
 
     def filter_contents(self, sha1s):
         """Filter out known sha1s and return only missing ones.
 
         """
         yield from self.storage.content_fossology_license_missing((
             {
                 'id': sha1,
                 'tool_name': self.tool_name,
                 'tool_version': self.tool_version
             } for sha1 in sha1s
         ))
 
     def index_content(self, sha1, content):
         """Index sha1s' content and store result.
 
         Args:
             sha1 (bytes): content's identifier
             content (bytes): raw content in bytes
 
         Returns:
             A dict, representing a content_license, with keys:
               - id (bytes): content's identifier (sha1)
               - license (bytes): license in bytes
               - path (bytes): path
 
         """
         filename = hashutil.hash_to_hex(sha1)
         content_path = self.write_to_temp(
             filename=filename,
             data=content)
 
-        properties = compute_license(self.tool, path=content_path)
-        properties.update({
-            'id': sha1,
-            'tool_name': self.tool_name,
-            'tool_version': self.tool_version,
-        })
+        try:
+            properties = compute_license(self.tool, path=content_path,
+                                         log=self.log)
+            properties.update({
+                'id': sha1,
+                'tool_name': self.tool_name,
+                'tool_version': self.tool_version,
+            })
+        finally:
+            self.cleanup(content_path)
 
-        self.cleanup(content_path)
         return properties
 
     def persist_index_computations(self, results, policy_update):
         """Persist the results in storage.
 
         Args:
             results ([dict]): list of content_license, dict with the
             following keys:
               - id (bytes): content's identifier (sha1)
               - license (bytes): license in bytes
               - path (bytes): path
             policy_update ([str]): either 'update-dups' or 'ignore-dups' to
             respectively update duplicates or ignore them
 
         """
         wrong_licenses = self.storage.content_fossology_license_add(
             results, conflict_update=(policy_update == 'update-dups'))
 
         if wrong_licenses:
             for l in wrong_licenses:
                 self.log.warn('Content %s has some unknown licenses: %s' % (
                     hashutil.hash_to_hex(l['id']),
                     ','.join((name for name in l['licenses'])))
                 )
 
 
 @click.command(help='Compute license for path using tool')
 @click.option('--tool', default='nomossa', help="Path to tool")
 @click.option('--path', required=1, help="Path to execute index on")
 def main(tool, path):
     print(compute_license(tool, path))
 
 
 if __name__ == '__main__':
     main()