With xcodebuild don't set CC, CXX, etc.

The compiler setting in the xcodeproj is overridden by the CC setting in the environment. This is a bit insane IMO since the xcodeproj itself has detailed decisions about what tools to use.

Fixes Homebrew/homebrew#6406.

1 files changed, 9 insertions, 0 deletions

diff --git a/Library/Homebrew/extend/ENV.rb b/Library/Homebrew/extend/ENV.rb
index abad5e76a..88cb5e2ac 100644
--- a/Library/Homebrew/extend/ENV.rb
+++ b/Library/Homebrew/extend/ENV.rb
@@ -351,4 +351,13 @@ Please take one of the following actions:
       Hardware.processor_count
     end
   end
+
+  def remove_cc_etc
+    keys = %w{CC CXX LD CPP LDFLAGS CFLAGS CPPFLAGS}
+    removed = Hash[*keys.map{ |key| [key, ENV[key]] }.flatten]
+    keys.each do |key|
+      ENV[key] = nil
+    end
+    removed
+  end
 end