Fix warnings produced by g++ on Windows.

src/IceTargetLoweringMIPS32.cpp

 //===- subzero/src/IceTargetLoweringMIPS32.cpp - MIPS32 lowering ----------===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 456 matching lines @@
   (void)Inst;
   UnimplementedError(Func->getContext()->getFlags());
 }
 
 void TargetMIPS32::lowerInsertElement(const InstInsertElement *Inst) {
   (void)Inst;
   UnimplementedError(Func->getContext()->getFlags());
 }
 
 void TargetMIPS32::lowerIntrinsicCall(const InstIntrinsicCall *Instr) {
-  switch (Intrinsics::IntrinsicID ID = Instr->getIntrinsicInfo().ID) {
+  switch (Instr->getIntrinsicInfo().ID) {
   case Intrinsics::AtomicCmpxchg: {
     UnimplementedError(Func->getContext()->getFlags());
     return;
   }
   case Intrinsics::AtomicFence:
     UnimplementedError(Func->getContext()->getFlags());
     return;
   case Intrinsics::AtomicFenceAll:
     // NOTE: FenceAll should prevent and load/store from being moved
     // across the fence (both atomic and non-atomic). The InstMIPS32Mfence
@@ skipping 230 matching lines @@
 void TargetDataMIPS32::lowerJumpTables() {
   if (Ctx->getFlags().getDisableTranslation())
     return;
   UnimplementedError(Ctx->getFlags());
 }
 
 TargetHeaderMIPS32::TargetHeaderMIPS32(GlobalContext *Ctx)
     : TargetHeaderLowering(Ctx) {}
 
 } // end of namespace Ice