Index: cfe/trunk/lib/Driver/Driver.cpp
===================================================================
--- cfe/trunk/lib/Driver/Driver.cpp
+++ cfe/trunk/lib/Driver/Driver.cpp
@@ -1490,6 +1490,10 @@
 
   // Claim ignored clang-cl options.
   Args.ClaimAllArgs(options::OPT_cl_ignored_Group);
+
+  // Claim --cuda-host-only arg which may be passed to non-CUDA
+  // compilations and should not trigger warnings there.
+  Args.ClaimAllArgs(options::OPT_cuda_host_only);
 }
 
 std::unique_ptr<Action>
Index: cfe/trunk/test/Driver/cuda-options.cu
===================================================================
--- cfe/trunk/test/Driver/cuda-options.cu
+++ cfe/trunk/test/Driver/cuda-options.cu
@@ -69,6 +69,20 @@
 // Make sure we don't link anything.
 // RUN:   -check-prefix CUDA-NL %s
 
+// --cuda-host-only should never trigger unused arg warning.
+// RUN: %clang -### -target x86_64-linux-gnu --cuda-host-only -c %s 2>&1 | \
+// RUN:    FileCheck -check-prefix CUDA-NO-UNUSED-CHO %s
+// RUN: %clang -### -target x86_64-linux-gnu --cuda-host-only -x c -c %s 2>&1 | \
+// RUN:    FileCheck -check-prefix CUDA-NO-UNUSED-CHO %s
+
+// --cuda-device-only should not produce warning compiling CUDA files
+// RUN: %clang -### -target x86_64-linux-gnu --cuda-device-only -c %s 2>&1 | \
+// RUN:    FileCheck -check-prefix CUDA-NO-UNUSED-CDO %s
+
+// --cuda-device-only should warn during non-CUDA compilation.
+// RUN: %clang -### -target x86_64-linux-gnu --cuda-device-only -x c -c %s 2>&1 | \
+// RUN:    FileCheck -check-prefix CUDA-UNUSED-CDO %s
+
 // Match device-side compilation
 // CUDA-D1: "-cc1" "-triple" "nvptx{{(64)?}}-nvidia-cuda"
 // CUDA-D1-SAME: "-fcuda-is-device"
@@ -109,3 +123,7 @@
 
 // Match no linker
 // CUDA-NL-NOT: "{{.*}}{{ld|link}}{{(.exe)?}}"
+
+// CUDA-NO-UNUSED-CHO-NOT: warning: argument unused during compilation: '--cuda-host-only'
+// CUDA-UNUSED-CDO: warning: argument unused during compilation: '--cuda-device-only'
+// CUDA-NO-UNUSED-CDO-NOT: warning: argument unused during compilation: '--cuda-device-only'