From 9b4fea602b474100a5fd8ac8a9f059db8bcddd59 Mon Sep 17 00:00:00 2001
From: David Cowden <dcow@pm.me>
Date: Wed, 13 Jan 2021 21:16:36 -0700
Subject: [PATCH] install: add workaround for rosetta2 path error msg

It's possible the user's terminal emulator is running under rosetta2.
Consequently, the i86_64 version of the ruby interpreter will be used.
Likely, the right thing to do is simply install the arm64 version of the
requested package. This can be accomplished using: arch -arm64 brew ...

Fixes: #10313
---
 Library/Homebrew/install.rb | 12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

diff --git a/Library/Homebrew/install.rb b/Library/Homebrew/install.rb
index 9b4ece01eb..a29b4803cd 100644
--- a/Library/Homebrew/install.rb
+++ b/Library/Homebrew/install.rb
@@ -32,12 +32,16 @@ module Homebrew
     def check_prefix
       if (Hardware::CPU.intel? || Hardware::CPU.in_rosetta2?) &&
          HOMEBREW_PREFIX.to_s == HOMEBREW_MACOS_ARM_DEFAULT_PREFIX
-        configuration = if Hardware::CPU.in_rosetta2?
-          "under Rosetta 2"
+        if Hardware::CPU.in_rosetta2?
+          configuration = "under Rosetta 2"
+          odie <<~EOS
+            Cannot install in Homebrew #{configuration} in ARM default prefix (#{HOMEBREW_PREFIX})!
+            Try `arch -arm64 brew install ...`
+          EOS
         else
-          "on Intel processor"
+          configuration = "on Intel processor"
+          odie "Cannot install in Homebrew #{configuration} in ARM default prefix (#{HOMEBREW_PREFIX})!"
         end
-        odie "Cannot install in Homebrew #{configuration} in ARM default prefix (#{HOMEBREW_PREFIX})!"
       elsif Hardware::CPU.arm? && HOMEBREW_PREFIX.to_s == HOMEBREW_DEFAULT_PREFIX
         odie <<~EOS
           Cannot install in Homebrew on ARM processor in Intel default prefix (#{HOMEBREW_PREFIX})!