From df27ddd93777d31ac4adb6f1b6689db2d4093792 Mon Sep 17 00:00:00 2001
From: Phil Elwell <8911409+pelwell@users.noreply.github.com>
Date: Fri, 16 Dec 2022 15:29:45 +0000
Subject: [PATCH] Update instructions for ARM-based Macs

See https://github.com/raspberrypi/usbboot/issues/176.
---
 Readme.md | 11 +++++++++++
 1 file changed, 11 insertions(+)

diff --git a/Readme.md b/Readme.md
index f2cf52e..2a7161a 100644
--- a/Readme.md
+++ b/Readme.md
@@ -57,6 +57,17 @@ sudo ./rpiboot
 If the build is unable to find the header file `libusb.h` then most likely the `PKG_CONFIG_PATH` is not set properly.
 This should be set via `export PKG_CONFIG_PATH="$(brew --prefix libusb)/lib/pkgconfig"`.
 
+If the build fails on an ARM-based Mac with a linker error such as `ld: warning: ignoring file /usr/local/Cellar/libusb/1.0.26/lib/libusb-1.0.dylib, building for macOS-arm64 but attempting to link with file built for macOS-x86_64` then you may need to build and install `libusb-1.0` yourself:
+```
+$ wget https://github.com/libusb/libusb/releases/download/v1.0.26/libusb-1.0.26.tar.bz2
+$ tar -xf libusb-1.0.26.tar.bz2
+$ cd libusb-1.0.26
+$ ./configure
+$ make
+$ make check
+$ sudo make install
+```
+Running `make` again should now succeed.
 
 ## Running