https://bugs.gentoo.org/891201#c9
https://gitlab.com/jgemu/bsnes/-/merge_requests/371
https://gitlab.com/jgemu/bsnes/-/commit/647e868f3d97bd937c46ecf312bbfbc25b816dc1

From 647e868f3d97bd937c46ecf312bbfbc25b816dc1 Mon Sep 17 00:00:00 2001
From: orbea <orbea@riseup.net>
Date: Sat, 9 Dec 2023 07:12:12 -0800
Subject: [PATCH] processor: update endian.hpp

Reference: https://sourceforge.net/p/predef/wiki/Endianness/
---
 src/processor/endian.hpp | 25 ++++++++++++++-----------
 1 file changed, 14 insertions(+), 11 deletions(-)

diff --git a/src/processor/endian.hpp b/src/processor/endian.hpp
index 3b6d93e..7d6ad04 100644
--- a/src/processor/endian.hpp
+++ b/src/processor/endian.hpp
@@ -1,25 +1,28 @@
 #pragma once
 
+// Reference: https://sourceforge.net/p/predef/wiki/Endianness/
+
 #if defined(__APPLE__)
   #include <machine/endian.h>
 #elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__NetBSD__) || defined(__OpenBSD__) || defined (__DragonFly__)
   #include <sys/endian.h>
 #endif
 
-#if  (defined(__BYTE_ORDER) && defined(__LITTLE_ENDIAN) && __BYTE_ORDER == __LITTLE_ENDIAN) \
-  || (defined( _BYTE_ORDER) && defined( _LITTLE_ENDIAN) &&  _BYTE_ORDER ==  _LITTLE_ENDIAN) \
-  || (defined(  BYTE_ORDER) && defined(  LITTLE_ENDIAN) &&   BYTE_ORDER ==   LITTLE_ENDIAN) \
-  || defined(__LITTLE_ENDIAN__) \
-  || defined(__i386__) || defined(__amd64__) || defined(__aarch64__) \
-  || defined(_M_IX86) || defined(_M_AMD64)
+#if (defined(__BYTE_ORDER) && __BYTE_ORDER == __LITTLE_ENDIAN) \
+    || (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_LITTLE_ENDIAN__) \
+    || (defined(__FLOAT_WORD_ORDER__) && __FLOAT_WORD_ORDER__ == __ORDER_LITTLE_ENDIAN__) \
+    || defined(__LITTLE_ENDIAN__) || defined(__ARMEL__) || defined(__THUMBEL__) \
+    || defined(__AARCH64EL__) || defined(_MIPSEL) || defined(__MIPSEL) \
+    || defined(__MIPSEL__) || defined(_WIN32) || defined(_WIN64)
   //little-endian: uint8_t[] { 0x01, 0x02, 0x03, 0x04 } == 0x04030201
   #define order_lsb2(a,b)             a,b
   #define order_lsb4(a,b,c,d)         a,b,c,d
-#elif(defined(__BYTE_ORDER) && defined(__BIG_ENDIAN) && __BYTE_ORDER == __BIG_ENDIAN) \
-  || (defined( _BYTE_ORDER) && defined( _BIG_ENDIAN) &&  _BYTE_ORDER ==  _BIG_ENDIAN) \
-  || (defined(  BYTE_ORDER) && defined(  BIG_ENDIAN) &&   BYTE_ORDER ==   BIG_ENDIAN) \
-  || defined(__BIG_ENDIAN__) \
-  || defined(__powerpc__) || defined(_M_PPC)
+#elif (defined(__BYTE_ORDER) && __BYTE_ORDER == __BIG_ENDIAN) \
+    || (defined(__BYTE_ORDER__) && __BYTE_ORDER__ == __ORDER_BIG_ENDIAN__) \
+    || (defined(__FLOAT_WORD_ORDER__) && __FLOAT_WORD_ORDER__ == __ORDER_BIG_ENDIAN__) \
+    || defined(__BIG_ENDIAN__) || defined(__ARMEB__) || defined(__THUMBEB__) \
+    || defined(__AARCH64EB__) || defined(_MIPSEB) || defined(__MIPSEB) \
+    || defined(__MIPSEB__) || defined(__powerpc__) || defined(_M_PPC)
   //big-endian:    uint8_t[] { 0x01, 0x02, 0x03, 0x04 } == 0x01020304
   #define order_lsb2(a,b)             b,a
   #define order_lsb4(a,b,c,d)         d,c,b,a