diff --git a/jps/jps-builders/src/org/jetbrains/jps/incremental/ModuleBuildTarget.java b/jps/jps-builders/src/org/jetbrains/jps/incremental/ModuleBuildTarget.java
index d8b7abb75be0..b30e37e146b4 100644
--- a/jps/jps-builders/src/org/jetbrains/jps/incremental/ModuleBuildTarget.java
+++ b/jps/jps-builders/src/org/jetbrains/jps/incremental/ModuleBuildTarget.java
@@ -169,7 +169,7 @@ public class ModuleBuildTarget extends ModuleBasedTarget<JavaSourceRootDescripto
     }
 
     for (String url : enumerator.classes().getUrls()) {
-      fingerprint += 31 * fingerprint + url.hashCode();
+      fingerprint = 31 * fingerprint + url.hashCode();
     }
     return fingerprint;
   }