diff --git a/include/llvm-c/Core.h b/include/llvm-c/Core.h
index 2bb7323..10e9a80b 100644
--- a/include/llvm-c/Core.h
+++ b/include/llvm-c/Core.h
@@ -179,8 +179,8 @@
   LLVMPHI            = 44,
   LLVMCall           = 45,
   LLVMSelect         = 46,
-  /* UserOp1 */
-  /* UserOp2 */
+  LLVMUserOp1        = 47,
+  LLVMUserOp2        = 48,
   LLVMVAArg          = 49,
   LLVMExtractElement = 50,
   LLVMInsertElement  = 51,
@@ -195,7 +195,9 @@
 
   /* Exception Handling Operators */
   LLVMResume         = 58,
-  LLVMLandingPad     = 59
+  LLVMLandingPad     = 59,
+  LLVMUnwind         = 60
+
 
 } LLVMOpcode;
 
diff --git a/lib/VMCore/Core.cpp b/lib/VMCore/Core.cpp
index a6f04ae..8241a80 100644
--- a/lib/VMCore/Core.cpp
+++ b/lib/VMCore/Core.cpp
@@ -654,10 +654,35 @@
   return wrap(ConstantVector::get(makeArrayRef(
                             unwrap<Constant>(ScalarConstantVals, Size), Size)));
 }
+
+/*-- Opcode mapping */
+
+static LLVMOpcode map_to_llvmopcode(int opcode)
+{
+    switch (opcode) {
+#define HANDLE_INST(num, opc, clas) case num: return LLVM##opc;
+#include "llvm/Instruction.def"
+#undef HANDLE_INST
+	default:
+	    assert(false && "Unhandled Opcode.");
+    }
+}
+
+static int map_from_llvmopcode(LLVMOpcode code)
+{
+    switch (code) {
+#define HANDLE_INST(num, opc, clas) case LLVM##opc: return num;
+#include "llvm/Instruction.def"
+#undef HANDLE_INST
+	default:
+	    assert(false && "Unhandled Opcode.");
+    }
+}
+
 /*--.. Constant expressions ................................................--*/
 
 LLVMOpcode LLVMGetConstOpcode(LLVMValueRef ConstantVal) {
-  return (LLVMOpcode)unwrap<ConstantExpr>(ConstantVal)->getOpcode();
+  return map_to_llvmopcode(unwrap<ConstantExpr>(ConstantVal)->getOpcode());
 }
 
 LLVMValueRef LLVMAlignOf(LLVMTypeRef Ty) {
@@ -1919,7 +1944,7 @@
 LLVMValueRef LLVMBuildBinOp(LLVMBuilderRef B, LLVMOpcode Op,
                             LLVMValueRef LHS, LLVMValueRef RHS,
                             const char *Name) {
-  return wrap(unwrap(B)->CreateBinOp(Instruction::BinaryOps(Op), unwrap(LHS),
+  return wrap(unwrap(B)->CreateBinOp(Instruction::BinaryOps(map_from_llvmopcode(Op)), unwrap(LHS),
                                      unwrap(RHS), Name));
 }
 
@@ -2106,7 +2131,7 @@
 
 LLVMValueRef LLVMBuildCast(LLVMBuilderRef B, LLVMOpcode Op, LLVMValueRef Val,
                            LLVMTypeRef DestTy, const char *Name) {
-  return wrap(unwrap(B)->CreateCast(Instruction::CastOps(Op), unwrap(Val),
+  return wrap(unwrap(B)->CreateCast(Instruction::CastOps(map_from_llvmopcode(Op)), unwrap(Val),
                                     unwrap(DestTy), Name));
 }