Index: lib/Frontend/FrontendOptions.cpp
===================================================================
--- lib/Frontend/FrontendOptions.cpp
+++ lib/Frontend/FrontendOptions.cpp
@@ -29,7 +29,7 @@
       .Case("cppm", Language::CXX)
       .Case("iim", InputKind(Language::CXX).getPreprocessed())
       .Case("cl", Language::OpenCL)
-      .Case("cu", Language::CUDA)
+      .Cases("cu", "cuh", Language::CUDA)
       .Cases("ll", "bc", Language::LLVM_IR)
       .Default(Language::Unknown);
 }