Index: lib/Driver/SanitizerArgs.cpp
===================================================================
--- lib/Driver/SanitizerArgs.cpp
+++ lib/Driver/SanitizerArgs.cpp
@@ -115,6 +115,8 @@
     llvm::sys::path::append(Path, "share", BL.File);
     if (llvm::sys::fs::exists(Path))
       BlacklistFiles.push_back(Path.str());
+    else
+      D.Diag(clang::diag::err_drv_no_such_file) << Path;
   }
 }