diff --git a/Library/Homebrew/os/mac/xcode.rb b/Library/Homebrew/os/mac/xcode.rb
index 2941f3d43234b5d1096921e88062bd0777fb582f..e6b2368995de449814da551c8676d38c97fd1e05 100644
--- a/Library/Homebrew/os/mac/xcode.rb
+++ b/Library/Homebrew/os/mac/xcode.rb
@@ -178,7 +178,7 @@ module OS
         else
           version = `/usr/bin/clang --version`
         end
-        version = version[%r{clang-(\d+\.\d+\.\d+)}, 1] || "0"
+        version = version[%r{clang-(\d+\.\d+\.\d+(\.\d+)?)}, 1] || "0"
         version < latest_version
       end