From a2a7edf4c8fa145667135bf1bc7f4f67016f7608 Mon Sep 17 00:00:00 2001
From: Tomasz Sobczyk <tomasz.sobczyk1997@gmail.com>
Date: Sun, 2 Jun 2024 20:39:25 +0200
Subject: [PATCH] Fix GetProcessGroupAffinity call

`GetProcessGroupAffinity` appears to require 4 byte alignment for `GroupArray` memory.

See https://stackoverflow.com/q/78567676 for further information

closes https://github.com/official-stockfish/Stockfish/pull/5340

No functional change
---
 src/numa.h | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/src/numa.h b/src/numa.h
index 967e24a6..5934a0cd 100644
--- a/src/numa.h
+++ b/src/numa.h
@@ -773,8 +773,8 @@ class NumaConfig {
                 return std::nullopt;
 
             // We are expecting a single group.
-            USHORT GroupCount = 1;
-            USHORT GroupArray[1];
+            USHORT            GroupCount = 1;
+            alignas(4) USHORT GroupArray[1];
             status = GetProcessGroupAffinity_f(GetCurrentProcess(), &GroupCount, GroupArray);
             if (status == 0 || GroupCount != 1)
                 return std::nullopt;