diff --git a/src/add-ons/kernel/file_cache/rule_based_prefetcher.cpp b/src/add-ons/kernel/file_cache/rule_based_prefetcher.cpp
index 23fdf72e8f..af0a7a7125 100644
--- a/src/add-ons/kernel/file_cache/rule_based_prefetcher.cpp
+++ b/src/add-ons/kernel/file_cache/rule_based_prefetcher.cpp
@@ -553,9 +553,14 @@ Rule::Dump()
 
 
 RuleMatcher::RuleMatcher(team_id team, const char *name)
+	:
+	fRules(NULL)
 {
 	recursive_lock_lock(&sLock);
 
+	if (name == NULL)
+		return;
+
 	fRules = (team_rules *)hash_lookup(sTeamHash, &team);
 	if (fRules != NULL)
 		return;