Index: llvm/lib/Transforms/IPO/GlobalOpt.cpp
===================================================================
--- llvm/lib/Transforms/IPO/GlobalOpt.cpp
+++ llvm/lib/Transforms/IPO/GlobalOpt.cpp
@@ -777,14 +777,6 @@
           UI = V->user_begin();
         }
       }
-    } else if (CastInst *CI = dyn_cast<CastInst>(I)) {
-      Changed |= OptimizeAwayTrappingUsesOfValue(CI,
-                                ConstantExpr::getCast(CI->getOpcode(),
-                                                      NewV, CI->getType()));
-      if (CI->use_empty()) {
-        Changed = true;
-        CI->eraseFromParent();
-      }
     } else if (GetElementPtrInst *GEPI = dyn_cast<GetElementPtrInst>(I)) {
       // Should handle GEP here.
       SmallVector<Constant*, 8> Idxs;