1 files changed, 1 insertions, 0 deletions
diff --git a/t/io/dup.t b/t/io/dup.t
index 8247b8e6ef..48497fd232 100755
--- a/t/io/dup.t
+++ b/t/io/dup.t
@@ -7,6 +7,7 @@ BEGIN {
 }
 
 use Config;
+no warnings 'once';
 
 my $test = 1;
 print "1..26\n";