Ada version cheat sheet (2012 vs. 2005 vs. '95 ...) ?

[julian.fondren@gmail.com]

Howdy,

For my personal development environments, Ada 2012 is totally fine, and
I know that some features I especially like require it ('with' pre/post
conditions, for some/all expressions), but it's come up that it might
benefit a project to be compileable by older compilers. For example,
CentOS 6 only offers an Ada 2005 package.

Is there a cheat sheet of the form, "in place of this Ada 2012
construct, you can use this Ada 2005 equivalent (or workaround)"?

Ada 2012:

   function getrusage (Who : Integer; Report : access RUsage) return Integer
      with Import => True, Convention => C, External_Name => "getrusage";

Ada 2005:

   function getrusage (Who : Integer; Report : access RUsage) return Integer;
   pragma Import (C, getrusage, "getrusage");

Or is my best bet to use an older compiler (or flag like -gnat05, where
available), and then look in older versions of the ARM for what fails?

Thanks.