diff --git a/src/ifcopenshell-python/ifcopenshell/validate.py b/src/ifcopenshell-python/ifcopenshell/validate.py
index 8675de8443..b5015bb1c9 100644
--- a/src/ifcopenshell-python/ifcopenshell/validate.py
+++ b/src/ifcopenshell-python/ifcopenshell/validate.py
@@ -206,7 +206,7 @@ def log_internal_cpp_errors(filename, logger):
     import re
     import bisect
 
-    chr_offset_re = re.compile("at offset (\d+)\s*")
+    chr_offset_re = re.compile(r"at offset (\d+)\s*")
 
     log = ifcopenshell.get_log()
     msgs = list(map(json.loads, filter(None, log.split("\n"))))