diff --git a/Library/Homebrew/macos.rb b/Library/Homebrew/macos.rb
index 4a941d613b..1359d2b484 100644
--- a/Library/Homebrew/macos.rb
+++ b/Library/Homebrew/macos.rb
@@ -57,8 +57,7 @@ module MacOS extend self
   end
 
   def tools_in_prefix?(prefix)
-    File.directory?(prefix) &&
-      %w{cc make}.all? { |tool| File.executable? "#{prefix}/usr/bin/#{tool}" }
+    %w{cc make}.all? { |tool| File.executable? "#{prefix}/usr/bin/#{tool}" }
   end
 
   def xctoolchain_path