The trace module was trying to turn ints into ints since co_lnotab was changed

to a bytes object.

Lib/trace.py

@@ -367,7 +367,7 @@ def find_lines_from_code(code, strs):
     """Return dict where keys are lines in the line number table."""
     linenos = {}
 
-    line_increments = [ord(c) for c in code.co_lnotab[1::2]]
+    line_increments = code.co_lnotab[1::2]
     table_length = len(line_increments)
     docstring = False
 

Misc/NEWS

@@ -147,6 +147,9 @@ Core and Builtins
 Library
 -------
 
+- Fix a bug in the trace module where a bytes object from co_lnotab had its
+  items being passed through ord().
+
 - Issue #2047: shutil.move() could believe that its destination path was
   inside its source path if it began with the same letters (e.g. "src" vs.
   "src.new").