Minor fix for dummy outputs

src/operator/OperatorTensor.cpp

@@ -141,7 +141,9 @@ bool Aidge::OperatorTensor::outputDimsForwarded() const {
         forwarded &= mInputs[i] ? !(getInput(i)->empty()) : false;
     }
     for (IOIndex_t i = 0; i < nbOutputs(); ++i) {
-        forwarded &= !(getOutput(i)->empty());
+        // If getOutput(i) is nullptr, ignore this output (it may be a dummy
+        // output in a MetaOperator)
+        forwarded &= (getOutput(i)) ? !(getOutput(i)->empty()) : true;
     }
     return forwarded;
 }