Re: gnat GPL 2010 or gcc/ada?

[Tero Koskinen <tero.koskinen@iki.fi>]

On Mon, 07 Mar 2011 17:23:15 +0100 Georg Bauhaus wrote:
> On 07.03.11 16:35, Julian Leyh wrote:
> > You'd have to test your program with all the compilers you want it to
> > be compilable with, i.e. compile it with both, GNAT-GPL and GCC-GNAT.
> 
> Chances are that all Ada compilers will compile
> standard Ada programs.  This shouldn't be too
> limiting for non-graphical, non-networked programs.

You apparently haven't tried many Ada compilers. :)

I seem to hit more or less constantly into various compiler
bugs when I am developing Ahven or other related projects and testing
them with four or five different compilers (FSF GNAT, GNAT GPL, Janus/Ada,
Irvine ICCAda, ObjectAda) on 3 platforms (Windows, Linux, OpenBSD).

For example, two different Ada compilers choked on this (rather largish)
change:
https://bitbucket.org/tkoskine/ahven-timeout/changeset/91a9f910a64b#chg_src/ahven-framework.adb_newline147

One compiler didn't like "case Results.Get_Status is"[1] and other compiler
simply dead-locked when the final program was run. Third compiler accepted
code as-is and the end result also behaved as expected.

I am trying to say that, in my experience, you shouldn't assume that
all Ada compilers will compile standard Ada programs. You need to actually
test that. Ahven's commit logs are littered with various "Work-around for XXX"
messages.

Oh, and if this compiling thing is too easy, try same with all warnings
turned on for all compilers. :)

-- 
Tero Koskinen - http://iki.fi/tero.koskinen/

[1] https://bitbucket.org/tkoskine/ahven-timeout/changeset/91a9f910a64b#chg_src/ahven-framework.adb_newline250