[Debian-science-sagemath] Sagemath Build-Depends backported - unfortunately build error (Was: Help needed to backport ipywidgets ... (Was: Backporting sagemath))

[Tobias Hansen]

As the error message says, with gcc 4.9 one needs to use the flag
-std=c++11 to have support for this. I added that flag in the git branch
debian/jessie-backports-c++11, please try. Here with gcc 6.3 this breaks
the pruner check for lcalc, but maybe it's fine with gcc 4.9. If that
does not work we can probably get it to work by applying -std=c++11 more
carefully.

Best,
Tobias

On 04/12/2017 10:15 AM, Andreas Tille wrote:
> Hi Tobias,
> 
> On Wed, Apr 12, 2017 at 08:59:06AM +0100, Tobias Hansen wrote:
>>> This check does not find the header for some reason:
>>>
>>> checking fplll/fplll.h usability... no
>>> checking fplll/fplll.h presence... no
>>> checking for fplll/fplll.h... no
>>>
>>> However the file exists in the backported libfplll-dev package. Not sure
>>> yet what's the problem.
>>
>> You should be able to see what's happening in debian/pruner/config.log.
> 
> This log says:
> 
> In file included from conftest.cpp:52:0:
> /usr/include/fplll/fplll.h:22:2: error: #error fplll needs at least a C++11 compliant compiler
>  #error fplll needs at least a C++11 compliant compiler
>   ^
> In file included from /usr/include/c++/4.9/array:35:0,
>                  from /usr/include/fplll/enum/enumerate.h:21,
>                  from /usr/include/fplll/bkz.h:23,
>                  from /usr/include/fplll/fplll.h:28,
>                  from conftest.cpp:52:
> /usr/include/c++/4.9/bits/c++0x_warning.h:32:2: error: #error This file requires compiler and library support for the ISO C++ 2011 standard. This support is currently experimental, and must be enabled with the -std=c++11 or -std=gnu++11 compiler options.
>  #error This file requires compiler and library support for the \
>   ^
> In file included from /usr/include/fplll/nr/nr.h:17:0,
>                  from /usr/include/fplll/nr/numvect.h:19,
>                  from /usr/include/fplll/nr/matrix.h:21,
>                  from /usr/include/fplll/util.h:23,
>                  from /usr/include/fplll/fplll.h:25,
>                  from conftest.cpp:52:
> /usr/include/fplll/nr/nr_FP.inl:326:35: error: expected unqualified-id before '&&' token
>  template <class F> inline FP_NR<F>&& operator+(FP_NR<F> &&a, const FP_NR<F> &b)
>                                    ^
> /usr/include/fplll/nr/nr_FP.inl:413:35: error: expected unqualified-id before '&&' token
>  template <class F> inline FP_NR<F>&& operator*(FP_NR<F> &&a, const FP_NR<F> &b) {
>                                    ^
> ...
> 
> 
> Do I need to backport even a compiler since the issue seems to be
> triggered by[1]
> 
> ...
>  #if __cplusplus < 201103L
>  #error fplll needs at least a C++11 compliant compiler
>  #endif
> ...
> 
> 
> Any ideas?
> 
> Kind regards
> 
>        Andreas.
> 
> [1] https://fplll.github.io/fplll/fplll_8h_source.html
> 
>