diff --git a/tools/c-index-test/c-index-test.c b/tools/c-index-test/c-index-test.c
index d0d5b2b..44b90b1 100644
--- a/tools/c-index-test/c-index-test.c
+++ b/tools/c-index-test/c-index-test.c
@@ -2552,7 +2552,7 @@
     printRanges(D, indent);
     printFixIts(D, indent);
     
-    // Print subdiagnostics.
+    /* Print subdiagnostics. */
     printDiagnosticSet(clang_getChildDiagnostics(D), indent+2);
 
     clang_disposeString(FileName);