diff --git a/mlir/lib/IR/TypeUtilities.cpp b/mlir/lib/IR/TypeUtilities.cpp
--- a/mlir/lib/IR/TypeUtilities.cpp
+++ b/mlir/lib/IR/TypeUtilities.cpp
@@ -126,6 +126,19 @@
   if (!llvm::all_of(shapedTypes, [](auto t) { return t; }))
     return failure();
 
+  // Return failure if some, but not all, are scalable vectors.
+  bool hasScalableVecTypes = false;
+  bool hasNonScalableVecTypes = false;
+  for (Type t : types) {
+    auto vType = t.dyn_cast<VectorType>();
+    if (vType && vType.isScalable())
+      hasScalableVecTypes = true;
+    else
+      hasNonScalableVecTypes = true;
+    if (hasScalableVecTypes && hasNonScalableVecTypes)
+      return failure();
+  }
+
   // Remove all unranked shapes
   auto shapes = llvm::to_vector<8>(llvm::make_filter_range(
       shapedTypes, [](auto shapedType) { return shapedType.hasRank(); }));
diff --git a/mlir/test/Dialect/Arithmetic/invalid.mlir b/mlir/test/Dialect/Arithmetic/invalid.mlir
--- a/mlir/test/Dialect/Arithmetic/invalid.mlir
+++ b/mlir/test/Dialect/Arithmetic/invalid.mlir
@@ -553,3 +553,163 @@
   %0 = arith.trunci %arg0 : i16 to i16
   return
 }
+
+// -----
+
+func @trunci_scalable_to_fl(%arg0 : vector<[4]xi32>) {
+  // expected-error@+1 {{'arith.trunci' op requires the same shape for all operands and results}}
+  %0 = arith.trunci %arg0 : vector<[4]xi32> to vector<4xi8>
+  return
+}
+
+// -----
+
+func @truncf_scalable_to_fl(%arg0 : vector<[4]xf64>) {
+  // expected-error@+1 {{'arith.truncf' op requires the same shape for all operands and results}}
+  %0 = arith.truncf %arg0 : vector<[4]xf64> to vector<4xf32>
+  return
+}
+
+// -----
+
+func @extui_scalable_to_fl(%arg0 : vector<[4]xi32>) {
+  // expected-error@+1 {{'arith.extui' op requires the same shape for all operands and results}}
+  %0 = arith.extui %arg0 : vector<[4]xi32> to vector<4xi64>
+  return
+}
+
+// -----
+
+func @extsi_scalable_to_fl(%arg0 : vector<[4]xi32>) {
+  // expected-error@+1 {{'arith.extsi' op requires the same shape for all operands and results}}
+  %0 = arith.extsi %arg0 : vector<[4]xi32> to vector<4xi64>
+  return
+}
+
+// -----
+
+func @extf_scalable_to_fl(%arg0 : vector<[4]xf32>) {
+  // expected-error@+1 {{'arith.extf' op requires the same shape for all operands and results}}
+  %0 = arith.extf %arg0 : vector<[4]xf32> to vector<4xf64>
+  return
+}
+
+// -----
+
+func @fptoui_scalable_to_fl(%arg0 : vector<[4]xf64>) {
+  // expected-error@+1 {{'arith.fptoui' op requires the same shape for all operands and results}}
+  %0 = arith.fptoui %arg0 : vector<[4]xf64> to vector<4xi32>
+  return
+}
+
+// -----
+
+func @fptosi_scalable_to_fl(%arg0 : vector<[4]xf32>) {
+  // expected-error@+1 {{'arith.fptosi' op requires the same shape for all operands and results}}
+  %0 = arith.fptosi %arg0 : vector<[4]xf32> to vector<4xi32>
+  return
+}
+
+// -----
+
+func @uitofp_scalable_to_fl(%arg0 : vector<[4]xi32>) {
+  // expected-error@+1 {{'arith.uitofp' op requires the same shape for all operands and results}}
+  %0 = arith.uitofp %arg0 : vector<[4]xi32> to vector<4xf32>
+  return
+}
+
+// -----
+
+func @sitofp_scalable_to_fl(%arg0 : vector<[4]xi32>) {
+  // expected-error@+1 {{'arith.sitofp' op requires the same shape for all operands and results}}
+  %0 = arith.sitofp %arg0 : vector<[4]xi32> to vector<4xf32>
+  return
+}
+
+// -----
+
+func @bitcast_scalable_to_fl(%arg0 : vector<[4]xf32>) {
+  // expected-error@+1 {{'arith.bitcast' op requires the same shape for all operands and results}}
+  %0 = arith.bitcast %arg0 : vector<[4]xf32> to vector<4xi32>
+  return
+}
+
+// -----
+
+func @trunci_fl_to_scalable(%arg0 : vector<4xi32>) {
+  // expected-error@+1 {{'arith.trunci' op requires the same shape for all operands and results}}
+  %0 = arith.trunci %arg0 : vector<4xi32> to vector<[4]xi8>
+  return
+}
+
+// -----
+
+func @truncf_fl_to_scalable(%arg0 : vector<4xf64>) {
+  // expected-error@+1 {{'arith.truncf' op requires the same shape for all operands and results}}
+  %0 = arith.truncf %arg0 : vector<4xf64> to vector<[4]xf32>
+  return
+}
+
+// -----
+
+func @extui_fl_to_scalable(%arg0 : vector<4xi32>) {
+  // expected-error@+1 {{'arith.extui' op requires the same shape for all operands and results}}
+  %0 = arith.extui %arg0 : vector<4xi32> to vector<[4]xi64>
+  return
+}
+
+// -----
+
+func @extsi_fl_to_scalable(%arg0 : vector<4xi32>) {
+  // expected-error@+1 {{'arith.extsi' op requires the same shape for all operands and results}}
+  %0 = arith.extsi %arg0 : vector<4xi32> to vector<[4]xi64>
+  return
+}
+
+// -----
+
+func @extf_fl_to_scalable(%arg0 : vector<4xf32>) {
+  // expected-error@+1 {{'arith.extf' op requires the same shape for all operands and results}}
+  %0 = arith.extf %arg0 : vector<4xf32> to vector<[4]xf64>
+  return
+}
+
+// -----
+
+func @fptoui_fl_to_scalable(%arg0 : vector<4xf64>) {
+  // expected-error@+1 {{'arith.fptoui' op requires the same shape for all operands and results}}
+  %0 = arith.fptoui %arg0 : vector<4xf64> to vector<[4]xi32>
+  return
+}
+
+// -----
+
+func @fptosi_fl_to_scalable(%arg0 : vector<4xf32>) {
+  // expected-error@+1 {{'arith.fptosi' op requires the same shape for all operands and results}}
+  %0 = arith.fptosi %arg0 : vector<4xf32> to vector<[4]xi32>
+  return
+}
+
+// -----
+
+func @uitofp_fl_to_scalable(%arg0 : vector<4xi32>) {
+  // expected-error@+1 {{'arith.uitofp' op requires the same shape for all operands and results}}
+  %0 = arith.uitofp %arg0 : vector<4xi32> to vector<[4]xf32>
+  return
+}
+
+// -----
+
+func @sitofp_fl_to_scalable(%arg0 : vector<4xi32>) {
+  // expected-error@+1 {{'arith.sitofp' op requires the same shape for all operands and results}}
+  %0 = arith.sitofp %arg0 : vector<4xi32> to vector<[4]xf32>
+  return
+}
+
+// -----
+
+func @bitcast_fl_to_scalable(%arg0 : vector<4xf32>) {
+  // expected-error@+1 {{'arith.bitcast' op requires the same shape for all operands and results}}
+  %0 = arith.bitcast %arg0 : vector<4xf32> to vector<[4]xi32>
+  return
+}