diff --git a/mlir/lib/Bytecode/Reader/BytecodeReader.cpp b/mlir/lib/Bytecode/Reader/BytecodeReader.cpp
--- a/mlir/lib/Bytecode/Reader/BytecodeReader.cpp
+++ b/mlir/lib/Bytecode/Reader/BytecodeReader.cpp
@@ -271,6 +271,8 @@
     return parseBytes(static_cast<size_t>(length), sectionData);
   }
 
+  Location getLoc() const { return fileLoc; }
+
 private:
   /// Parse a variable length encoded integer from the byte stream. This method
   /// is a fallback when the number of bytes used to encode the value is greater
@@ -835,6 +837,13 @@
     return reader.emitError(msg);
   }
 
+  DialectReader withEncodingReader(EncodingReader &encReader) {
+    return DialectReader(attrTypeReader, stringReader, resourceReader,
+                         encReader);
+  }
+
+  Location getLoc() const { return reader.getLoc(); }
+
   //===--------------------------------------------------------------------===//
   // IR
   //===--------------------------------------------------------------------===//
@@ -1054,7 +1063,6 @@
   DialectReader dialectReader(*this, stringReader, resourceReader, reader);
   if (failed(entry.dialect->load(dialectReader, fileLoc.getContext())))
     return failure();
-
   // Ensure that the dialect implements the bytecode interface.
   if (!entry.dialect->interface) {
     return reader.emitError("dialect '", entry.dialect->name,
@@ -1378,7 +1386,9 @@
              << name
              << "' does not implement the bytecode interface, "
                 "but found a version entry";
-    loadedVersion = interface->readVersion(reader);
+    EncodingReader encReader(versionBuffer, reader.getLoc());
+    DialectReader versionReader = reader.withEncodingReader(encReader);
+    loadedVersion = interface->readVersion(versionReader);
     if (!loadedVersion)
       return failure();
   }
@@ -1448,9 +1458,8 @@
   // haven't, load the dialect and build the operation name.
   if (!opName->opName) {
     // Load the dialect and its version.
-    EncodingReader versionReader(opName->dialect->versionBuffer, fileLoc);
     DialectReader dialectReader(attrTypeReader, stringReader, resourceReader,
-                                versionReader);
+                                reader);
     if (failed(opName->dialect->load(dialectReader, getContext())))
       return failure();
     opName->opName.emplace((opName->dialect->name + "." + opName->name).str(),
diff --git a/mlir/test/Bytecode/general.mlir b/mlir/test/Bytecode/general.mlir
--- a/mlir/test/Bytecode/general.mlir
+++ b/mlir/test/Bytecode/general.mlir
@@ -4,6 +4,7 @@
 // UNSUPPORTED: target=s390x-{{.*}}
 
 // CHECK-LABEL: "bytecode.test1"
+// CHECK-NEXT:    "unregistered.op"() {test_attr = #test.dynamic_singleton} : () -> ()
 // CHECK-NEXT:    "bytecode.empty"() : () -> ()
 // CHECK-NEXT:    "bytecode.attributes"() {attra = 10 : i64, attrb = #bytecode.attr} : () -> ()
 // CHECK-NEXT{LITERAL}: "bytecode.sparse"() {value = sparse<[[2, 1], [1, 1], [1, 2]], [1.
@@ -21,6 +22,7 @@
 // CHECK-NEXT:  }) : () -> ()
 
 "bytecode.test1"() ({
+  "unregistered.op"() {test_attr = #test.dynamic_singleton} : () -> ()
   "bytecode.empty"() : () -> ()
   "bytecode.attributes"() {attra = 10, attrb = #bytecode.attr} : () -> ()
   %cst = "bytecode.sparse"() {value = sparse<[[2, 1], [1, 1], [1, 2]], [1.0, 5.0, 6.0]> : tensor<8x7xf32>} : () -> (tensor<8x7xf32>)
diff --git a/mlir/test/lib/Dialect/Test/TestDialect.cpp b/mlir/test/lib/Dialect/Test/TestDialect.cpp
--- a/mlir/test/lib/Dialect/Test/TestDialect.cpp
+++ b/mlir/test/lib/Dialect/Test/TestDialect.cpp
@@ -128,8 +128,7 @@
       writer.writeVarInt(concreteAttr.getV1());
       return success();
     }
-    writer.writeAttribute(attr);
-    return success();
+    return failure();
   }
 
   Attribute readAttribute(DialectBytecodeReader &reader,