diff --git a/t/test-lib-functions.sh b/t/test-lib-functions.sh
index c64e5a5025..8d99eb303f 100644
--- a/t/test-lib-functions.sh
+++ b/t/test-lib-functions.sh
@@ -617,7 +617,7 @@ test_must_fail () {
 		return 0
 	elif test $exit_code -gt 129 && test $exit_code -le 192
 	then
-		echo >&2 "test_must_fail: died by signal: $*"
+		echo >&2 "test_must_fail: died by signal $(($exit_code - 128)): $*"
 		return 1
 	elif test $exit_code -eq 127
 	then