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

[Tobias Hansen]

On 04/12/2017 07:59 PM, Andreas Tille wrote:
> Hi Tobias,
> 
> On Wed, Apr 12, 2017 at 03:51:46PM +0100, Tobias Hansen wrote:
>>
>> I pushed to a new branch because that commit was just something to test
>> and probably not to keep. And it turned out as rubbish.
> 
> ... its reverted.  I'd agree with your commit policy in complex cases
> but in our case it might be more complex to maintain to many branches.
>  
>> I think you should for now just bypass this precheck and see if sage
>> builds. I think it should be able to build with gcc 4.9 just fine and
>> put the right --std=c++11 flags itself.
>>
>> You can disable the pruner check for fplll by replacing the relevant
>> bits in debian/pruner/configure.ac by
>>
>> # FIXME(fplll): Disable check for jessie-backports because it fails with
>> gcc 4.9
>> HAS_FPLLL="True"
>> AC_SUBST(HAS_FPLLL)
> 
> I've commited this and it helped for the described case.  Now there is
> an error inside the test suite.  I'm attaching the full log.
> 

The error is this:

[sagelib-7.4] x86_64-linux-gnu-gcc -pthread -shared -Wl,-O1
-Wl,-Bsymbolic-functions -Wl,-z,relro -fno-strict-aliasing -DNDEBUG -g
-fwrapv -O2 -Wall -Wstrict-prototypes -D_FORTIFY_SOURCE=2 -g
-fstack-protector-strong -Wformat -Werror=format-security
-L/build/sagemath-7.4/debian/build/usr/lib -Wl,-z,relro -g -O2
-fstack-protector-strong -Wformat -Werror=format-security
-D_FORTIFY_SOURCE=2
build/temp.linux-x86_64-2.7/build/sagemath-7.4/sage/src/build/cythonized/sage/ext/interpreters/wrapper_rdf.o
build/temp.linux-x86_64-2.7/sage/ext/interpreters/interp_rdf.o
-L/build/sagemath-7.4/debian/build/usr/lib -lgsl -lgslcblas -lm -lm -o
build/lib.linux-x86_64-2.7/sage/ext/interpreters/wrapper_rdf.so
[sagelib-7.4] /usr/bin/ld:
/usr/lib/gcc/x86_64-linux-gnu/4.9/../../../x86_64-linux-gnu/libgslcblas.a(sgemm.o):
relocation R_X86_64_32 against `.rodata.str1.1' can not be used when
making a shared object; recompile with -fPIC
[sagelib-7.4]
/usr/lib/gcc/x86_64-linux-gnu/4.9/../../../x86_64-linux-gnu/libgslcblas.a:
error adding symbols: Bad value
[sagelib-7.4] collect2: error: ld returned 1 exit status

The problem seems to be that the shared library libgslcblas0 was removed
from the package gsl in version 2.3+dfsg-1~bpo8+2 so now the static
library libgslcblas.a is used which does not work. ("recompile with
-fPIC" means use the shared library.)

Best,
Tobias