diff --git a/testing/btest/language/expire-func-undef.bro b/testing/btest/language/expire-func-undef.bro
index 1184cd2bf2..eb864d2390 100644
--- a/testing/btest/language/expire-func-undef.bro
+++ b/testing/btest/language/expire-func-undef.bro
@@ -1,5 +1,5 @@
 # @TEST-EXEC: bro -r $TRACES/rotation.trace -b %INPUT >output 2>&1
-# @TEST-EXEC: btest-diff output
+# @TEST-EXEC: TEST_DIFF_CANONIFIER=$SCRIPTS/diff-remove-abspath btest-diff output
 
 module segfault;