Turn assertion into bitcode reading error

I don't think we test invalid bitcode records in any detail, so no test
here - just a change for consistency with existing error checks in
surrounding code.

llvm-svn: 232215

llvm/lib/Bitcode/Reader/BitcodeReader.cpp

@@ -3126,8 +3126,8 @@ std::error_code BitcodeReader::ParseFunctionBody(Function *F) {
       }
 
       I = GetElementPtrInst::Create(BasePtr, GEPIdx);
-      (void)Ty;
-      assert(!Ty || Ty == cast<GetElementPtrInst>(I)->getSourceElementType());
+      if (Ty && Ty != cast<GetElementPtrInst>(I)->getSourceElementType())
+        return Error("Invalid record");
       InstructionList.push_back(I);
       if (InBounds)
         cast<GetElementPtrInst>(I)->setIsInBounds(true);