Re: Standalone (.exe) Ada Programs can run in isolation of any ada compiler - True or False ?

[Austin Obyrne <austin.obyrne@hotmail.com>]

On Thursday, February 5, 2015 at 11:33:39 PM UTC, Simon Wright wrote:
> Austin Obyrne <austin.obyrne@hotmail.com> writes:
> 
> > 1)Would some reader confirm that this true or false and explain the
> > mechanics of how it is done.
> 
> The Ada compiler translates the source code into object code, which is
> linked against Ada libraries (which come with the compiler) and system
> libraries to produce the executable.
> 
> After this point, the source code and the object code are no longer
> relevant.
> 
> The Ada libraries and the system libraries are usually dynamic libraries
> (.dll on Windows), which means that they are separate entities. When you
> run the .exe, the system first loads the .exe and then loads all the
> .dlls which it needs (and the ones they need, ...); then the system can
> actually run the program.
> 
> > 2)Is the ensuing (.exe) program then bound to that computer alone
> > i.e. customised for running in that environment only and will require
> > customising again to any other computer i.e. not generally portable
> > without some attention each time.
> 
> You don't need to worry about the system libraries, but the Ada
> libraries won't be present on machines that haven't had Ada installed;
> and they must match the .exe, so you can't mix a GNAT GPL 2014 .exe
> with a GNAT GPL 2013 .dll.
> 
> The simple way round this is to supply the .exe and the (Ada) .dlls it
> needs in one directory.
> 
> On my machine, the .dlls are libgnat-2014.dll and libgnarl-2014.dll,
> both in C:\GNAT\2014\lib\gcc\i686-pc-mingw32\4.7.4\adalib (together with
> a *lot* of other files!)
> 
> And, of course, this is Windows; you can't run the same .exe on Linux or
> Mac.

Many ,many thanks Simon - this is the advice I needed - I have no pretentions to being an Ada developer or indeed anything more than a hardworking problem solver on the back of a very successful career running ships.

Best Wishes - Austin O'Byrne