diff --git a/m4/groff.m4 b/m4/groff.m4
index 7d9350a..a3a58d9 100644
--- a/m4/groff.m4
+++ b/m4/groff.m4
@@ -397,7 +397,7 @@ exit 1
 EOF
 
    chmod +x conftest.sh
-   if echo ./conftest.sh | (csh >/dev/null 2>&1) >/dev/null 2>&1; then
+   if echo ./conftest.sh | (csh -f >/dev/null 2>&1) >/dev/null 2>&1; then
      AC_MSG_RESULT([yes])
      $1
    else