diff --git a/test_regress/t/t_timing_nba_3.py b/test_regress/t/t_timing_nba_3.py
index 7da1fcea5..ecf737948 100755
--- a/test_regress/t/t_timing_nba_3.py
+++ b/test_regress/t/t_timing_nba_3.py
@@ -11,7 +11,7 @@ import vltest_bootstrap
 
 test.scenarios('vlt')
 
-test.compile(verilator_flags2=["--binary", "--assert"])
+test.compile(verilator_flags2=["--binary", "--assert", "-Wno-ZERODLY"])
 
 test.execute()
 
diff --git a/test_regress/t/t_timing_nba_whole_partial.py b/test_regress/t/t_timing_nba_whole_partial.py
index 7da1fcea5..ecf737948 100755
--- a/test_regress/t/t_timing_nba_whole_partial.py
+++ b/test_regress/t/t_timing_nba_whole_partial.py
@@ -11,7 +11,7 @@ import vltest_bootstrap
 
 test.scenarios('vlt')
 
-test.compile(verilator_flags2=["--binary", "--assert"])
+test.compile(verilator_flags2=["--binary", "--assert", "-Wno-ZERODLY"])
 
 test.execute()