diff --git a/lib/VMCore/ValueTypes.cpp b/lib/VMCore/ValueTypes.cpp
index 99dc1de247e..d02a538eb24 100644
--- a/lib/VMCore/ValueTypes.cpp
+++ b/lib/VMCore/ValueTypes.cpp
@@ -20,12 +20,14 @@ using namespace llvm;
 MVT MVT::getExtendedIntegerVT(unsigned BitWidth) {
   MVT VT;
   VT.LLVMTy = IntegerType::get(BitWidth);
+  assert(VT.isExtended() && "Type is not extended!");
   return VT;
 }
 
 MVT MVT::getExtendedVectorVT(MVT VT, unsigned NumElements) {
   MVT ResultVT;
   ResultVT.LLVMTy = VectorType::get(VT.getTypeForMVT(), NumElements);
+  assert(ResultVT.isExtended() && "Type is not extended!");
   return ResultVT;
 }
 
diff --git a/utils/TableGen/TGValueTypes.cpp b/utils/TableGen/TGValueTypes.cpp
index 209e7c92c55..9e62322a63a 100644
--- a/utils/TableGen/TGValueTypes.cpp
+++ b/utils/TableGen/TGValueTypes.cpp
@@ -69,6 +69,7 @@ MVT MVT::getExtendedIntegerVT(unsigned BitWidth) {
   if (!ET) ET = new ExtendedIntegerType(BitWidth);
   MVT VT;
   VT.LLVMTy = ET;
+  assert(VT.isExtended() && "Type is not extended!");
   return VT;
 }
 
@@ -78,6 +79,7 @@ MVT MVT::getExtendedVectorVT(MVT VT, unsigned NumElements) {
   if (!ET) ET = new ExtendedVectorType(VT, NumElements);
   MVT ResultVT;
   ResultVT.LLVMTy = ET;
+  assert(ResultVT.isExtended() && "Type is not extended!");
   return ResultVT;
 }