diff --git a/Library/Homebrew/macos.rb b/Library/Homebrew/macos.rb
index b8c2a58f9d..ab3fe76d54 100644
--- a/Library/Homebrew/macos.rb
+++ b/Library/Homebrew/macos.rb
@@ -206,6 +206,7 @@ module MacOS extend self
     "4.6"   => { :llvm_build => 2336, :clang => "4.2", :clang_build => 425 },
     "4.6.1" => { :llvm_build => 2336, :clang => "4.2", :clang_build => 425 },
     "4.6.2" => { :llvm_build => 2336, :clang => "4.2", :clang_build => 425 },
+    "5.0"   => { :clang => "5.0", :clang_build => 500 },
   }
 
   def compilers_standard?
diff --git a/Library/Homebrew/os/mac/xcode.rb b/Library/Homebrew/os/mac/xcode.rb
index 30b01d88d5..873275fcce 100644
--- a/Library/Homebrew/os/mac/xcode.rb
+++ b/Library/Homebrew/os/mac/xcode.rb
@@ -23,10 +23,11 @@ module MacOS::Xcode extend self
     when 10.5       then "3.1.4"
     when 10.6       then "3.2.6"
     when 10.7, 10.8 then "4.6.2"
+    when 10.9       then "5.0"
     else
       # Default to newest known version of Xcode for unreleased OSX versions.
-      if MacOS.version > 10.8
-        "4.6.2"
+      if MacOS.version > 10.9
+        "5.0"
       else
         raise "Mac OS X '#{MacOS.version}' is invalid"
       end
@@ -127,6 +128,7 @@ module MacOS::Xcode extend self
       when 40      then "4.4"
       when 41      then "4.5"
       when 42      then "4.6"
+      when 50      then "5.0"
       else "4.6"
       end
     end