diff --git a/src/dxgi/dxgi_adapter.cpp b/src/dxgi/dxgi_adapter.cpp
index 9415932e..44861bfd 100644
--- a/src/dxgi/dxgi_adapter.cpp
+++ b/src/dxgi/dxgi_adapter.cpp
@@ -125,7 +125,7 @@ namespace dxvk {
     }
     
     std::memset(pDesc->Description, 0, sizeof(pDesc->Description));
-    std::mbstowcs(pDesc->Description, deviceProp.deviceName, _countof(pDesc->Description) - 1);
+    std::mbstowcs(pDesc->Description, deviceProp.deviceName, std::size(pDesc->Description) - 1);
     
     VkDeviceSize deviceMemory = 0;
     VkDeviceSize sharedMemory = 0;
diff --git a/src/dxgi/dxgi_output.cpp b/src/dxgi/dxgi_output.cpp
index 759147a5..5159ee0f 100644
--- a/src/dxgi/dxgi_output.cpp
+++ b/src/dxgi/dxgi_output.cpp
@@ -144,7 +144,7 @@ namespace dxvk {
     }
     
     std::memset(pDesc->DeviceName, 0, sizeof(pDesc->DeviceName));
-    std::mbstowcs(pDesc->DeviceName, monInfo.szDevice, _countof(pDesc->DeviceName) - 1);
+    std::mbstowcs(pDesc->DeviceName, monInfo.szDevice, std::size(pDesc->DeviceName) - 1);
     
     pDesc->DesktopCoordinates = monInfo.rcMonitor;
     pDesc->AttachedToDesktop  = 1;