From fadfe844470759dfb77f3589c9b2e9d57c0587b8 Mon Sep 17 00:00:00 2001
From: Elliott Sales de Andrade <quantum.analyst@gmail.com>
Date: Sat, 13 Jul 2024 11:20:24 -0700
Subject: [PATCH] Backport PR #28534: [BLD] Fix WSL build warning

---
 src/_image_resample.h | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/_image_resample.h b/src/_image_resample.h
index 745fe9f10cd7..a6404092ea2d 100644
--- a/src/_image_resample.h
+++ b/src/_image_resample.h
@@ -500,7 +500,7 @@ typedef enum {
 
 // T is rgba if and only if it has an T::r field.
 template<typename T, typename = void> struct is_grayscale : std::true_type {};
-template<typename T> struct is_grayscale<T, decltype(T::r, void())> : std::false_type {};
+template<typename T> struct is_grayscale<T, std::void_t<decltype(T::r)>> : std::false_type {};
 
 
 template<typename color_type>