diff --git a/tools/convert-group b/tools/convert-group
index 81ad9934..981aa87c 100755
--- a/tools/convert-group
+++ b/tools/convert-group
@@ -16,6 +16,8 @@ obliterate_group_file() {
 		elif [ ! -e "$test" ]; then
 			echo "Ignoring unknown test file \"$test\"."
 			continue
+		elif grep -q '^_begin_fstest' "$test"; then
+			continue
 		fi
 
 		# Replace all the open-coded test preparation code with a