Add a bit of error handling to google benchmark

python/dune/codegen/sumfact/autotune.py

@@ -363,7 +363,11 @@ def autotune_realization(sf):
             if get_option("autotune_google_benchmark"):
                 import json
                 with open(logname) as json_file:
-                    data = json.load(json_file)
-                    return data['benchmarks'][0]['cpu_time']
+                    try:
+                        data = json.load(json_file)
+                        return data['benchmarks'][0]['cpu_time']
+                    except Exception as e:
+                        print("Error while loading file {}".format(logname))
+                        raise e
             else:
                 return float(next(iter(open(logname, "r")))) / 1000000