diff --git a/platform/core-api/src/com/intellij/usageView/UsageInfo.java b/platform/core-api/src/com/intellij/usageView/UsageInfo.java
index e9e51bcf2501..15e6e0611d81 100644
--- a/platform/core-api/src/com/intellij/usageView/UsageInfo.java
+++ b/platform/core-api/src/com/intellij/usageView/UsageInfo.java
@@ -55,10 +55,18 @@ public class UsageInfo {
     else {
       effectiveStart = startOffset;
       effectiveEnd = endOffset;
-      if (element != originalElement && originalElement.getContainingFile() == file) {
-        int delta = originalElement.getTextRange().getStartOffset() - elementRange.getStartOffset();
-        effectiveStart += delta;
-        effectiveEnd += delta;
+      if (element != originalElement) {
+        PsiFile originalFile = originalElement.getContainingFile();
+        if (originalFile == file) {
+          int delta = originalElement.getTextRange().getStartOffset() - elementRange.getStartOffset();
+          effectiveStart += delta;
+          effectiveEnd += delta;
+        }
+        else {
+          throw new IllegalArgumentException("element.getNavigationElement() for element "+originalElement+"("+startOffset+", "+endOffset+
+               ") from " + originalFile + " led to different file "+file+
+               ", thus making passed offsets invalid. Specify -1 for start/end offsets to calculate correct offsets for navigation.");
+        }
       }
     }