Isnan

[Andreas Enge <andreas@enge.fr>]

Hello,

has anyone followed what the deal is with isnan in core-updates? A number
of C++ packages does not build any more. For instance, dealii:
solver_control.cc:96:24: error: ‘isnan’ was not declared in this scope
       isnan(check_value) ||
                        ^
[ 30%] Building CXX object source/lac/CMakeFiles/obj_lac.debug.dir/solver_control.cc.o
cd /tmp/guix-build-dealii-8.2.1.drv-0/build/source/lac && /gnu/store/frrj3bfbmg5vrd0flh9cf8j64h7cr2v4-gcc-4.9.3/bin/c++   -DDEBUG -I/tmp/guix-build-dealii-8.2.1.drv-0/build/source/lac -I/tmp/guix-build-dealii-8.2.1.drv-0/build/include -I/tmp/guix-build-dealii-8.2.1.drv-0/dealii-8.2.1/include -I/gnu/store/pzk986yikywnql4x393pbhzbiz7vl72n-bzip2-1.0.6/include -I/gnu/store/f51hs67f3g1r15fy9xq4bi7m3z991p0j-tbb-4.3.2/include -I/gnu/store/5992iq1v7arqa14ym3di58n4la0893nv-zlib-1.2.8/include -I/gnu/store/5qp29kq39b23w0sb1306fhsrq0zfm6sl-suitesparse-4.4.3/include -I/gnu/store/693zbcqs6jv8zg7k1x8x8k3sm7fimqs0-boost-1.60.0/include -I/gnu/store/8vqdr67rfbxk12bl3gajshkiffn8l9ld-muparser-2.2.5-2/include  -pedantic -fpic -Wall -Wpointer-arith -Wwrite-strings -Wsynth -Wsign-compare -Wswitch -Wno-unused-local-typedefs -Wno-long-long -Wno-deprecated -Wno-deprecated-declarations -fopenmp-simd -std=c++11 -Og -ggdb -Wa,--compress-debug-sections -o CMakeFiles/obj_lac.debug.dir/solver_control.cc.o -c /tmp/guix-build-dealii-8.2.1.drv-0/dealii-8.2.1/source/lac/solver_control.cc
/tmp/guix-build-dealii-8.2.1.drv-0/dealii-8.2.1/source/lac/solver_control.cc: In member function ‘virtual dealii::SolverControl::State dealii::SolverControl::check(unsigned int, double)’:
/tmp/guix-build-dealii-8.2.1.drv-0/dealii-8.2.1/source/lac/solver_control.cc:96:24: error: ‘isnan’ was not declared in this scope
       isnan(check_value) ||
                        ^
/tmp/guix-build-dealii-8.2.1.drv-0/dealii-8.2.1/source/lac/solver_control.cc:96:24: note: suggested alternative:
In file included from /gnu/store/frrj3bfbmg5vrd0flh9cf8j64h7cr2v4-gcc-4.9.3/include/c++/complex:44:0,
                 from /tmp/guix-build-dealii-8.2.1.drv-0/dealii-8.2.1/include/deal.II/base/numbers.h:22,
                 from /tmp/guix-build-dealii-8.2.1.drv-0/build/include/deal.II/base/config.h:579,
                 from /tmp/guix-build-dealii-8.2.1.drv-0/dealii-8.2.1/include/deal.II/base/logstream.h:19,
                 from /tmp/guix-build-dealii-8.2.1.drv-0/dealii-8.2.1/source/lac/solver_control.cc:16:
/gnu/store/frrj3bfbmg5vrd0flh9cf8j64h7cr2v4-gcc-4.9.3/include/c++/cmath:632:5: note:   ‘std::isnan’
     isnan(_Tp __x)

Apparently the "std::" is missing in front of "isnan"; should this not be implicit?

Andreas