diff --git a/Library/Homebrew/os/mac.rb b/Library/Homebrew/os/mac.rb
index 067244c5fc..24c1b71818 100644
--- a/Library/Homebrew/os/mac.rb
+++ b/Library/Homebrew/os/mac.rb
@@ -99,7 +99,7 @@ module OS
 
     def default_cc
       cc = locate 'cc'
-      cc.realpath.basename.to_s rescue nil
+      Pathname.new(cc).realpath.basename.to_s rescue nil
     end
 
     def default_compiler