stop using arg_front


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@20599 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/CBackend/Writer.cpp b/lib/Target/CBackend/Writer.cpp
index 254b5a4..cebff75 100644
--- a/lib/Target/CBackend/Writer.cpp
+++ b/lib/Target/CBackend/Writer.cpp
@@ -1079,7 +1079,7 @@
       std::string ArgName;
       if (F->arg_begin()->hasName() || !Prototype)
         ArgName = Mang->getValueName(F->arg_begin());
-      printType(FunctionInnards, F->arg_front().getType(), ArgName);
+      printType(FunctionInnards, F->arg_begin()->getType(), ArgName);
       for (Function::const_arg_iterator I = ++F->arg_begin(), E = F->arg_end();
            I != E; ++I) {
         FunctionInnards << ", ";