From 58c7b56c609ed65119bc61a8ac3734e44a68f2a2 Mon Sep 17 00:00:00 2001
From: UltraHDR <108294295+UltraHDR@users.noreply.github.com>
Date: Wed, 9 Nov 2022 01:47:23 +0000
Subject: [PATCH] Add Apple Silicon build instructions (#280)

---
 BUILD.md | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

diff --git a/BUILD.md b/BUILD.md
index aeeec73f..d55c0ef6 100644
--- a/BUILD.md
+++ b/BUILD.md
@@ -59,19 +59,29 @@ You can use it by replacing the step 3 with the following:
  - If step 4 gives you a different error, you could report it to this repo or try using GCC. Just make sure your standard library and compilers are updated since Cemu uses a lot of modern features!
 - If step 4 gives you undefined libdecor_xx, you are likely experiencing an issue with sdl2 package that comes with vcpkg. Delete sdl2 from vcpkg.json in source file and recompile.
 
-## MacOS
+## macOS
 
 To compile Cemu, a recent enough compiler and STL with C++20 support is required! LLVM 13 and 
 below, built in LLVM, and Xcode LLVM don't support the C++20 feature set required. Currently, 
 LLVM 15 isn't supported due to compatibility issues with Boost dependency. The OpenGL graphics
-API isn't support on MacOS, Vulkan must be used. Additionally Vulkan must be used through the 
-Molten-VK compatibility layer.  
+API isn't support on macOS, Vulkan must be used. Additionally Vulkan must be used through the 
+Molten-VK compatibility layer
+
+### On Apple Silicon Macs, Rosetta 2 and the x86_64 version of Homebrew must be used
+
+You can skip this section if you have an Intel Mac. Every time you compile, you need to perform steps 2.
+
+1. `softwareupdate --install-rosetta` # Install Rosetta 2 if you don't have it. This only has to be done once
+2. `arch -x86_64 zsh` # run an x64 shell
 
 ### Installing brew
-`/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"`
+
+1. `/bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"`
+2. `eval "$(/usr/local/Homebrew/bin/brew shellenv)"` # set x86_64 brew env
 
 ### Installing dependencies
-`brew install git cmake llvm@14 ninja nasm molten-vk`
+
+`brew install boost git cmake llvm@14 ninja nasm molten-vk`
 
 ### Build Cemu using cmake and clang
 1. `git clone --recursive https://github.com/cemu-project/Cemu`