diff --git a/opm/simulators/wells/BlackoilWellModel_impl.hpp b/opm/simulators/wells/BlackoilWellModel_impl.hpp
index f17e60165..45e314d55 100644
--- a/opm/simulators/wells/BlackoilWellModel_impl.hpp
+++ b/opm/simulators/wells/BlackoilWellModel_impl.hpp
@@ -840,8 +840,8 @@ namespace Opm {
         const auto& perf_data = this->well_perf_data_[wellID];
 
         // Cater for case where local part might have no perforations.
-        const int pvtreg = perf_data.size() ?
-            pvt_region_idx_[perf_data.front().cell_index] : 0;
+        const int pvtreg = perf_data.empty() ?
+            0 : pvt_region_idx_[perf_data.front().cell_index];
         const auto& parallel_well_info = *local_parallel_well_info_[wellID];
         auto global_pvtreg = parallel_well_info.broadcastFirstPerforationValue(pvtreg);
 
diff --git a/opm/simulators/wells/WellState.hpp b/opm/simulators/wells/WellState.hpp
index 8b6a84e4c..dc87b080b 100644
--- a/opm/simulators/wells/WellState.hpp
+++ b/opm/simulators/wells/WellState.hpp
@@ -377,8 +377,8 @@ namespace Opm
                 : (prod_controls.cmode == Well::ProducerCMode::GRUP);
 
             const double inj_surf_rate = well.isInjector() ? inj_controls.surface_rate : 0.0; // To avoid a "maybe-uninitialized" warning.
-            const double local_pressure = well_perf_data_[w].size() ?
-                cellPressures[well_perf_data_[w][0].cell_index] : 0;
+            const double local_pressure = well_perf_data_[w].empty() ?
+                0 : cellPressures[well_perf_data_[w][0].cell_index];
             const double global_pressure = well_info.broadcastFirstPerforationValue(local_pressure);
             if (well.getStatus() == Well::Status::STOP) {
                 // Stopped well: