diff --git a/lib/Driver/Driver.cpp b/lib/Driver/Driver.cpp
index f06166e..f2e965c 100644
--- a/lib/Driver/Driver.cpp
+++ b/lib/Driver/Driver.cpp
@@ -665,6 +665,9 @@
                                 InputInfo &Result) const {
   llvm::PrettyStackTraceString CrashInfo("Building compilation jobs for action");
   if (const InputAction *IA = dyn_cast<InputAction>(A)) {
+    // FIXME: This is broken, linker inputs won't work here.
+    assert(isa<PositionalArg>(IA->getInputArg()) && "FIXME: Linker inputs");
+
     IA->getInputArg().claim();
     const char *Name = IA->getInputArg().getValue(C.getArgs());
     Result = InputInfo(Name, A->getType(), Name);