[llvm-commits] [llvm] r142456 - in /llvm/trunk/projects/sample: ./ autoconf/ autoconf/m4/

[Daniel Dunbar]

On Tue, Oct 18, 2011 at 11:11 PM, Anton Korobeynikov
<anton at korobeynikov.info> wrote:
> Hi Daniel,
>
> On Wed, Oct 19, 2011 at 03:10, Daniel Dunbar <daniel at zuster.org> wrote:
>> Author: ddunbar
>> Date: Tue Oct 18 18:10:47 2011
>> New Revision: 142456
>>
>> URL: http://llvm.org/viewvc/llvm-project?rev=142456&view=rev
>> Log:
>> projects/sample: Import adapted form of current LLVM autoconf/Makefile setup so that projects/sample is standalone and not tied to the LLVM build setup.
>>  - This currently just moves over all of the behavior from LLVM. Eventually all of the configure checks that are directly needed by the LLVM build setup should probably go away, and the project should manage their own configuration checks if necessary.
>
> How we make sure that actual Makefile's and samples/Makefile's will
> always be in sync?

We don't. Over time, I would prefer to actively rip out the overly
complex parts of the samples/Makefiles to be simpler and more tuned to
sample projects using LLVM (although I have no particular motivation
to spend a lot of time on this). Conversely, I do intend to actively
rip out things from LLVM's makefiles which were only there to support
sample projects.

> I somehow feel that code duplication is not a good approach here.

The point of projects/sample is to provide a ready made build +
structure for people who want to set up a project to use LLVM.
Ideally, it should only depend on llvm-config.

The way I see it, that is completely orthogonal to how LLVM itself
should build. I view the fact that they were previously in sync as a
bug, not a feature.

For example, realistic projects using LLVM would be much better served
by having a configuration that is pre-setup to support targeting
different versions of LLVM. This is incredibly useful and something we
hacked together in KLEE, but would make more sense to be part of the
standard template. Obviously, however, that kind of code has no
relevance to LLVM TOT.

 - Daniel

>
> --
> With best regards, Anton Korobeynikov
> Faculty of Mathematics and Mechanics, Saint Petersburg State University
>