Use unique'ed types for varargs expansion instead of non-unique named types.

lib/Transforms/NaCl/ExpandVarArgs.cpp

 //===- ExpandVarArgs.cpp - Expand out variable argument function calls-----===//
 //
 //                     The LLVM Compiler Infrastructure
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 //
 // This pass expands out all use of variable argument functions.
@@ skipping 212 matching lines @@
     // This allows va_arg to read an undefined value from the stack
     // rather than crashing by reading from an uninitialized pointer.
     // An alternative would be to pass a null pointer to catch the
     // invalid use of va_arg.
     VarArgsTypes.push_back(Type::getInt32Ty(*Context));
   }
 
   // Create struct type for packing variable arguments into.  We
   // create this as packed for now and assume that no alignment
   // padding is desired.
-  StructType *VarArgsTy = StructType::create(VarArgsTypes, "vararg_call", true);
+  StructType *VarArgsTy = StructType::get(*Context, VarArgsTypes, true);
 
   // Allocate space for the variable argument buffer.  Do this at the
   // start of the function so that we don't leak space if the function
   // is called in a loop.
   Function *Func = Call->getParent()->getParent();
   Instruction *Buf = new AllocaInst(VarArgsTy, "vararg_buffer");
   Func->getEntryBlock().getInstList().push_front(Buf);
 
   // Call llvm.lifetime.start/end intrinsics to indicate that Buf is
   // only used for the duration of the function call, so that the
@@ skipping 86 matching lines @@
       ExpandVarArgFunc(Func);
     }
   }
 
   return Changed;
 }
 
 ModulePass *llvm::createExpandVarArgsPass() {
   return new ExpandVarArgs();
 }