diff --git a/helpers/check-abi.py b/helpers/check-abi.py
--- a/helpers/check-abi.py
+++ b/helpers/check-abi.py
@@ -200,7 +200,7 @@
 	]
 	logging.debug(" ".join(cmd))
 	try:
-		prog = subprocess.run(cmd, check=True, capture_output=True)
+		prog = subprocess.run(cmd, check=True, stdout=subprocess.PIPE, stderr=subprocess.PIPE)
 	except subprocess.CalledProcessError as e:
 		if e.returncode == 1:    # that means that we are not compatible, but still valid output.
 			logging.warning("abi-compliance-checker exited with 1:\n%s", prog.stdout.decode())