corinthia-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From jan i <>
Subject Re: Is using Bison & Flex ok?
Date Mon, 17 Aug 2015 16:30:49 GMT
On 17 August 2015 at 18:16, Dennis E. Hamilton <>

> I think there are two aspects to the question of code-generation tools.  I
> think it is an useful topic to raise.
> First, the best maintainable source needs to be included (e.g., the input
> to Bison).  That is part of the Open Source Definition as I recall, and it
> applies to Apache projects.
> Secondly, if you intend to include the generated output (technically, a
> convenience, but not binary), that seems like the right thing to do also.
> Ideally the generation is reproducible by anyone who chooses to do so, and
> information on how it was generated can be included in the source.
> (If the *generated* file were modified manually later, I would make that a
> separate derived result, so someone can figure it out from the released
> source.)
> I don't think the build step needs to be part of the cmake process or
> whatever process for building from a Corinthia release, even though any
> script used might be part of the generation information.  A generation step
> is only needed by developers who want to make a derivative of the Bison
> input, and anyone capable of doing that will certainly obtain the necessary
> tooling for their own use.
> So, don't provide the tool, don't have it as an external dependency, and
> provide enough information so someone who cared could do the generation
> from Bison input themselves.
Of course not, we also do not provide compilers etc.

> CAVEAT #1: If the generation tool's license places conditions on the
> generated output that are more restrictive than the ALv2, that becomes a
> problem.  That depends on the Bison "special-exception" that is provided on
> the generated files themselves, it seems to me.
Having read them, I do not see them as more restrictive.

> CAVEAT #2: The way to deal with this is not to have it be a matter of
> opinion, if there remains any doubt about the "special-exception"
> statement.  There is a LEGAL section on the ASF JIRA for raising such
> specific questions (and I am a bit amazed that this has not happened
> already).
Why would we call for LEGAL help on a subject that is
a) an experiment, and probably will not come into production code
b) There is a fairly clear text, that do not seem stricter than ALv2
(because we do not modify the code)
c) You saw from the release discussion, that tools are irrelevant for a
release (together with libraries not included)
d) If every project that had an idea would ask LEGAL first, they would be
overburdened, we need them for real problems.

So in my opinion, let us wait and see, if Peter decides to use it in
production code, that is the point where we need to dig deeper. Bear in
mind we did exactly the same with the web editor.

jan i

>  - Dennis
> -----Original Message-----
> From: Peter Kelly []
> Sent: Monday, August 17, 2015 07:34
> To:
> Subject: Is using Bison & Flex ok?
> I’m currently doing writing some experimental code for developing &
> testing a type inference algorithm that will eventually become of Flat.
> Because the latter is not at a sufficient stage of maturity, I’m using
> Bison & Flex to parse a simple C-like programming language upon which I’m
> doing the analysis.
> I’d like to include this code in the repository, but wanted to confirm
> whether this is within the legal guidelines for dependent software. Bison
> is GPL, but has a special exception for the generated code (which contains
> part of Bison itself):
> [ ... ]

  • Unnamed multipart/alternative (inline, None, 0 bytes)
View raw message