diff --git a/Library/Homebrew/os/mac.rb b/Library/Homebrew/os/mac.rb
index 2f47aa2a32..fd19c3d12d 100644
--- a/Library/Homebrew/os/mac.rb
+++ b/Library/Homebrew/os/mac.rb
@@ -124,7 +124,7 @@ module OS
       (@non_apple_gcc_version ||= {}).fetch(cc) do
         path = HOMEBREW_PREFIX.join("opt", "gcc", "bin", cc)
         path = locate(cc) unless path.exist?
-        version = %x{#{path} --version}[/gcc(?:-\d\.\d \(.+\))? (\d\.\d\.\d)/, 1] if path
+        version = %x{#{path} --version}[/gcc(?:-\d(?:\.\d)? \(.+\))? (\d\.\d\.\d)/, 1] if path
         @non_apple_gcc_version[cc] = version
       end
     end