diff --git a/mlir/include/mlir/IR/AttributeSupport.h b/mlir/include/mlir/IR/AttributeSupport.h
--- a/mlir/include/mlir/IR/AttributeSupport.h
+++ b/mlir/include/mlir/IR/AttributeSupport.h
@@ -16,6 +16,7 @@
 #include "mlir/IR/MLIRContext.h"
 #include "mlir/IR/StorageUniquerSupport.h"
 #include "llvm/ADT/PointerIntPair.h"
+#include "llvm/ADT/Twine.h"
 
 namespace mlir {
 class MLIRContext;
@@ -153,6 +154,13 @@
   static typename std::enable_if_t<
       std::is_same<typename T::ImplType, AttributeStorage>::value, T>
   get(MLIRContext *ctx) {
+#ifndef NDEBUG
+    if (!ctx->getAttributeUniquer().isInitialized(T::getTypeID()))
+      llvm::report_fatal_error(llvm::Twine("can't create Attribute '") +
+                               llvm::getTypeName<T>() +
+                               "' because storage uniquer isn't initialized: "
+                               "the dialect was likely not loaded.");
+#endif
     return ctx->getAttributeUniquer().get<typename T::ImplType>(T::getTypeID());
   }
 
diff --git a/mlir/include/mlir/IR/TypeSupport.h b/mlir/include/mlir/IR/TypeSupport.h
--- a/mlir/include/mlir/IR/TypeSupport.h
+++ b/mlir/include/mlir/IR/TypeSupport.h
@@ -15,6 +15,8 @@
 
 #include "mlir/IR/MLIRContext.h"
 #include "mlir/IR/StorageUniquerSupport.h"
+#include "llvm/ADT/Twine.h"
+#include "llvm/Support/TypeName.h"
 
 namespace mlir {
 class Dialect;
@@ -137,6 +139,13 @@
   static typename std::enable_if_t<
       std::is_same<typename T::ImplType, TypeStorage>::value, T>
   get(MLIRContext *ctx) {
+#ifndef NDEBUG
+    if (!ctx->getTypeUniquer().isInitialized(T::getTypeID()))
+      llvm::report_fatal_error(llvm::Twine("can't create type '") +
+                               llvm::getTypeName<T>() +
+                               "' because storage uniquer isn't initialized: "
+                               "the dialect was likely not loaded.");
+#endif
     return ctx->getTypeUniquer().get<typename T::ImplType>(T::getTypeID());
   }
 
diff --git a/mlir/include/mlir/Support/StorageUniquer.h b/mlir/include/mlir/Support/StorageUniquer.h
--- a/mlir/include/mlir/Support/StorageUniquer.h
+++ b/mlir/include/mlir/Support/StorageUniquer.h
@@ -210,6 +210,11 @@
     return get<Storage>(TypeID::get<Storage>());
   }
 
+  /// Test if there is a storage uniquer initialized for the provided TypeID.
+  /// This is only useful for debugging/diagnostic purpose: the uniquer is
+  /// initialized when a dialect is loaded.
+  bool isInitialized(TypeID id);
+
   /// Changes the mutable component of 'storage' by forwarding the trailing
   /// arguments to the 'mutate' function of the derived class.
   template <typename Storage, typename... Args>
diff --git a/mlir/lib/Support/StorageUniquer.cpp b/mlir/lib/Support/StorageUniquer.cpp
--- a/mlir/lib/Support/StorageUniquer.cpp
+++ b/mlir/lib/Support/StorageUniquer.cpp
@@ -176,6 +176,9 @@
     return singletonInstance;
   }
 
+  /// Check if an instance of a singleton storage class exists.
+  bool hasSingleton(TypeID id) { return singletonInstances.count(id); }
+
   //===--------------------------------------------------------------------===//
   // Instance Storage
   //===--------------------------------------------------------------------===//
@@ -227,6 +230,9 @@
   return impl->getSingleton(id);
 }
 
+/// Test is the storage singleton is initialized.
+bool StorageUniquer::isInitialized(TypeID id) { return impl->hasSingleton(id); }
+
 /// Implementation for registering an instance of a derived type with default
 /// storage.
 void StorageUniquer::registerSingletonImpl(