diff --git a/amaranth/hdl/_ir.py b/amaranth/hdl/_ir.py
index f9bec3d..cbb940b 100644
--- a/amaranth/hdl/_ir.py
+++ b/amaranth/hdl/_ir.py
@@ -26,7 +26,7 @@ class Elaboratable(_unused.MustUse):
     _MustUse__warning = UnusedElaboratable
 
 
-class DriverConflict(UserWarning):
+class DriverConflict(Exception):
     pass