diff --git a/CMakeLists.txt b/CMakeLists.txt
index 35425db..28c555a 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -128,7 +128,7 @@ if(SPDLOG_FMT_EXTERNAL)
     target_link_libraries(spdlog_header_only INTERFACE fmt::fmt)
     
     if (WIN32)
-        target_compile_options(spdlog PRIVATE /wd4275)
+        target_compile_options(spdlog PRIVATE /wd4275 /wd4100)
     endif()
 
     set(PKG_CONFIG_REQUIRES fmt) # add dependecy to pkg-config
diff --git a/include/spdlog/details/os-inl.h b/include/spdlog/details/os-inl.h
index f436b0d..82f3510 100644
--- a/include/spdlog/details/os-inl.h
+++ b/include/spdlog/details/os-inl.h
@@ -128,7 +128,7 @@ SPDLOG_INLINE void prevent_child_fd(FILE *f)
 {
 
 #ifdef _WIN32
-#if !defined(__cplusplus_winrt)
+#if WINAPI_FAMILY_PARTITION(WINAPI_PARTITION_DESKTOP | WINAPI_PARTITION_SYSTEM)
     auto file_handle = reinterpret_cast<HANDLE>(_get_osfhandle(_fileno(f)));
     if (!::SetHandleInformation(file_handle, HANDLE_FLAG_INHERIT, 0))
         SPDLOG_THROW(spdlog_ex("SetHandleInformation failed", errno));