1 files changed, 3 insertions, 0 deletions
diff --git a/check.py b/check.py
index 4c84a004d..345a3b302 100755
--- a/check.py
+++ b/check.py
@@ -148,6 +148,9 @@ for asm in tests:
         finally:
           if old_pass_debug is not None:
             os.environ['BINARYEN_PASS_DEBUG'] = old_pass_debug
+          else:
+            if 'BINARYEN_PASS_DEBUG' in os.environ:
+              del os.environ['BINARYEN_PASS_DEBUG']
 
         # verify in wasm
         if options.interpreter: