diff --git a/ethosu/regor/compiler/graphir_optimiser.cpp b/ethosu/regor/compiler/graphir_optimiser.cpp
index d0c3b5a593362e33f65dda6f4bc8230c749a0f51..4732e46477d81abaaccf60e4c8759346bf0d1fb9 100644
--- a/ethosu/regor/compiler/graphir_optimiser.cpp
+++ b/ethosu/regor/compiler/graphir_optimiser.cpp
@@ -742,7 +742,7 @@ Operation *GraphIrOptimiser::RewritePad(Graph *const, Operation *const operation
         const Shape ofmShape = ofmConn->shape;
         const auto &paramsConn = operation->Input(TensorUsage::Params);
         const auto &attr = operation->Attribute<pad_attr_t>();
-        uint8_t zeroPoint = ofmConn->quantization.IsValid() ? uint8_t(ofmConn->quantization.zeroPoints[0]) : 0;
+        const int zeroPoint = ofmConn->quantization.IsValid() ? static_cast<int>(ofmConn->quantization.zeroPoints[0]) : 0;
         const int padConst = int(attr->pad_const) + zeroPoint;
 
         // Decode the padding before and after each dimension as two shapes
diff --git a/ethosu/regor/compiler/tflite_graph_optimiser.cpp b/ethosu/regor/compiler/tflite_graph_optimiser.cpp
index e4a4db81697f60792629e25d45881726e234d297..3aa93dc97e7fc77af84ad884bd26719abbf2a889 100644
--- a/ethosu/regor/compiler/tflite_graph_optimiser.cpp
+++ b/ethosu/regor/compiler/tflite_graph_optimiser.cpp
@@ -2527,7 +2527,7 @@ Operation *TFLiteGraphOptimiser::ConvertPadV2(Graph *const graph, Operation *con
         const auto padConstTens = operation->Input(TensorUsage::Params1)->tensor;
         // This is undoing the existing zero point adjustment to counteract the zero point adjustment
         // which is done in GraphIR lowering of Pad.
-        uint8_t zeroPoint = ofmConn->quantization.IsValid() ? uint8_t(ofmConn->quantization.zeroPoints[0]) : 0;
+        int zeroPoint = ofmConn->quantization.IsValid() ? static_cast<int>(ofmConn->quantization.zeroPoints[0]) : 0;
         attr->pad_const = padConstTens->View().Values<int>(padConstTens->Type())[0] - zeroPoint;
 
         RecordOptimisation(operation, padOp.get());