diff --git a/libcxx/utils/libcxx/test/tracing.py b/libcxx/utils/libcxx/test/tracing.py
--- a/libcxx/utils/libcxx/test/tracing.py
+++ b/libcxx/utils/libcxx/test/tracing.py
@@ -14,7 +14,7 @@
     def wrapper(*args, **kwargs):
         kwarg_strs = ['{}={}'.format(k, v) for (k, v) in kwargs]
         arg_str = ', '.join([str(a) for a in args] + kwarg_strs)
-        call_str = '{}({})'.format(function.func_name, arg_str)
+        call_str = '{}({})'.format(function.__name__, arg_str)
 
         # Perform the call itself, logging before, after, and anything thrown.
         try: