diff --git a/benchmarks/utils/__init__.py b/benchmarks/utils/__init__.py
index c8f9ad4911d723c26ba3e388ac58cf7fb1247732_YmVuY2htYXJrcy91dGlscy9fX2luaXRfXy5weQ==..94b53f56284893d756e425de8f4f13b1f1ed9f5f_YmVuY2htYXJrcy91dGlscy9fX2luaXRfXy5weQ== 100644
--- a/benchmarks/utils/__init__.py
+++ b/benchmarks/utils/__init__.py
@@ -514,7 +514,12 @@
     def has_command(self, cmd):
         """return true if the command exist at the current version"""
         try:
-            self.hg('--config', 'ui.strict=yes', 'help', '--command', cmd)
+            self.hg('--config',
+                    'ui.strict=yes',
+                    'help',
+                    '--command',
+                    cmd,
+                    stderr=subprocess.STDOUT)
         except subprocess.CalledProcessError as exc:
             if exc.returncode != 255:
                 raise