Commercial ada compilers vs gcc ada compilier

Commercial ada compilers vs gcc ada compilier

[Alain De Vos]

What do commercial ada compilers provide more than the gcc ones for the user of them? 
In short what can I do with one what I cannot do with the other for legal raisons ? And what with the use of external libraries.

Re: Commercial ada compilers vs gcc ada compilier

[Dmitry A. Kazakov]

On 2019-11-05 18:12, Alain De Vos wrote:
> What do commercial ada compilers provide more than the gcc ones for the user of them?

GNAT Pro offers excellent support and laxer license.

-- 
Regards,
Dmitry A. Kazakov
http://www.dmitry-kazakov.de

Re: Commercial ada compilers vs gcc ada compilier

[Shark8]

On Tuesday, November 5, 2019 at 10:12:08 AM UTC-7, Alain De Vos wrote:
> What do commercial ada compilers provide more than the gcc ones for the user of them?
More diversity in the ecosystem, error-checking (having multiple compilers compiling the same source and checking the operation of the compiled output against them is good for ensuring the standard is being implemented correctly), some of them also have some nice proprietary libraries that may be pretty useful.

> In short what can I do with one what I cannot do with the other for legal raisons ? And what with the use of external libraries.
The legal-complications are (IMO) due to there being three 'versions' of GNAT:
1: AdaCore's Community edition, which has a GPLed runtime.
2: AdaCore's Pro edition, which does not.
3: FSF's edition which has runtime- and generic-exception [IIRC] to the GPL.

Re: Commercial ada compilers vs gcc ada compilier

[Simon Wright]

Shark8 <onewingedshark@gmail.com> writes:

> The legal-complications are (IMO) due to there being three 'versions' of GNAT:
> 1: AdaCore's Community edition, which has a GPLed runtime.
> 2: AdaCore's Pro edition, which does not.
> 3: FSF's edition which has runtime- and generic-exception [IIRC] to the GPL.

I don't know what the legal position is with licence terms written in
each individual file vs licence terms specified elsewhere.

I no longer have access to any Pro editions, but

* the FSF sources contain the runtime exception
* the CE sources are (aside from a few differences caused by them coming
  from different commits in AdaCore's source tree) identical to the FSF
  sources but having the runtime exception caluses edited out of the
  licence header.

from which I deduce that there's really only one source tree, with
different releases.

So I'd expect that the individual source files of the Pro runtime
contain the runtime exception. There are (were) additional guarantees
from AdaCore about customers' abilty to use the code in proprietary
systems.

Now, back when AdaCore were removing the GMGPL from their CE-equivalent
libraries, they hadn't got round to the wheeze of programattically
stripping out the GMGPL terms from source files, and Robert Dewar
claimed that a notice in the source tree to the effect that, whatever
the individual files said in their headers, the library as a whole was
released under the pure GPL.

I always thought this was a dodgy argument, given that FSF's guidelines
for how to release your code under the GPL say and said that you should
put the licence terms in each source file
(e.g. https://www.gnu.org/licenses/gpl-faq.en.html#NoticeInSourceFile).

Re: Commercial ada compilers vs gcc ada compilier

[Stephen Leake]

On Tuesday, November 5, 2019 at 9:12:08 AM UTC-8, Alain De Vos wrote:
> What do commercial ada compilers provide more than the gcc ones for the user of them? 
> In short what can I do with one what I cannot do with the other for legal raisons ? And what with the use of external libraries.

Your question is poorly phrased; "gcc" is a commercial compiler, because there is at least one company that will sell you support for it (AdaCore), and you can use it to produce products that you sell.

I suspect by "commercial" you mean "_not_ Free Software" and by "gcc" you mean "Free Software". The other answers seem to assume that.

It is best to be clear, and to use terms correctly.

Re: Commercial ada compilers vs gcc ada compilier

[Norman Worth]

Alain De Vos wrote:
> What do commercial ada compilers provide more than the gcc ones for the user of them?
> In short what can I do with one what I cannot do with the other for legal raisons ? And what with the use of external libraries.
> 
To a large extent, it depends on personal taste.  All the different 
compilers do some things a bit differently.  You may find one of the 
commercial compilers easier to use than GNAT, or easier to manage files 
for, or a better fit for your operations, etc.  The compilers also 
handle the compilation process somewhat differently, and so you may find 
the results better for one than another.  For instance, many years ago, 
I found that Janus Ada handled generics much better than GNAT and 
therefore produced smaller code, which was vital on a Z-80.