[Dune] first release candidate for 2.6 release

[Simon Praetorius]

Thanks for providing this release candidate,

I have tried to compile dune 2.6.0rc1 on our cluster Taurus a  
TU-Dresden with gcc and intel compilers and have encountered some  
problems I want to share here. Some are minor and some are bigger  
issues:

My library setups is:
---------------------
CMake 3.9.0, BullXMPI 1.2.8.4, METIS 5.1.0, ParMETIS 4.0.3, MKL 2015/2017


Compiler GCC 6.2.0:
-------------------
- (different) warnings: 7
- errors: 1

dune-istl/dune/istl/repartition.hh:1381:27: error: cannot convert  
'float*' to 'real_t* {aka double*}' for argument '10' to 'int  
ParMETIS_V3_PartKway'

The error is related to how ParMETIS is compiled on a system. On my  
system it uses `double` pointers. See appended text for a simple  
solution


compiler Intel 2015 (15.0.3):
-----------------------------
- cmake: Unable to determine C++ standard support for the compiler.  
Needs to set manually DISABLE_CXX_VERSION_CHECK=1,  
CXX_MAX_SUPPORTED_STANDARD=14, and CMAKE_CXX_FLAGS="-std=c++14"
- warnings: > 3
- errors: > 8 (some are related errors)

main issue: intel 15 is compatible with gcc up to 4.9 (and uses  
libstdc++ and headers from this gcc version on my system)
-> e.g. std::is_trivially_copyable not implemented
-> no generic lambda (or at least not fully supported)
-> constexpr functions can not return void
    (  
https://stackoverflow.com/questions/29261276/constexpr-void-function-rejected  
)


compilers intel 2016-2017:
--------------------------
similar as above. Number of errors reduced by not to 0


compiler intel 2018 (18.0.1):
-----------------------------
- warnings: 7
- errors: 6


The errors are all of the same kind on different places in the code  
and related to, what I think, is a bug in the intel compilers. In a  
Hybrid::forEach, inside the lambda, the names from namespace  
Dune::Hybrid are not found, although `using namespace Dune::Hybrid` is  
stated before the call to `forEach`. These errors are simple to  
workaround, i.e. simply add an additional `using namespace  
Dune::Hybrid` inside the lambda. But this is not very beautiful and  
will be forgotten probably in implementations in the future. Maybe we  
have to formulate a style-guide for `Hybrid::forEach` calls.


--------

Since, intel 2015 is limited to gcc 4.9, I think the support may be  
dropped. But intel 2016 supports gcc 5.1 and thus I hope, we could  
make Dune compatible with this compiler at least, maybe with some  
small workarounds.

See appended the list of warnings and errors I've found when just  
compiling the dune modules and tests from dune-common, dune-geometry,  
dune-grid, dune-istl, dune-localfunctions.

Best wishes,
Simon Praetorius


Zitat von Andreas Dedner <a.s.dedner at warwick.ac.uk>:

> Hi everyone.
>
> We just wanted to let you know that just in time for Christmas the first
> release candidate of the 2.6 release is available for testing.
> Tar balls are available
> https://www.dune-project.org/releases/2.6.0rc1/
> or use the v2.6.0rc1 tag for helping us, by testing the release with
> your own modules, system, workflow... Let us know if you encounter any
> problems. Also please skim through the change log (same link as above)
> to see if something is unclear or missing.
>
> Wish you all a merry Christmas and a happy new year
> Andreas and Martin
>
> _______________________________________________
> Dune mailing list
> Dune at lists.dune-project.org
> http://lists.dune-project.org/mailman/listinfo/dune



-- 
Dr. Simon Praetorius
Institut für Wissenschaftliches Rechnen
Fakultät Mathematik
Technische Universität Dresden
Tel.: TUD-34432
Mail: simon.praetorius at tu-dresden.de
Web: www.math.tu-dresden.de/~spraetor
-------------- next part --------------
An embedded and charset-unspecified text was scrubbed...
Name: compile_log_dune_2.6.0rc1.txt
URL: <https://lists.dune-project.org/pipermail/dune/attachments/20180108/009312f6/attachment.txt>
-------------- next part --------------
A non-text attachment was scrubbed...
Name: smime.p7s
Type: application/pkcs7-signature
Size: 5753 bytes
Desc: S/MIME-Signatur
URL: <https://lists.dune-project.org/pipermail/dune/attachments/20180108/009312f6/attachment.bin>