Build error because of isnan()

[rdiez]

I got the following build error because of isnan():

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scons: Reading SConscript files ...
Build type: release
Using C++ compiler... g++
Checking for C++ library spnav... (cached) yes
Checking for C++ header file boost/signals2/signal.hpp... (cached) yes
Checking for C++ library exif... (cached) yes
Checking for C++ library sqlite3... (cached) yes
Checking for C library jpeg... (cached) yes
Checking for C++ library GL... (cached) yes
Checking for C++ library GLEW... (cached) yes
scons: done reading SConscript files.
scons: Building targets ...
scons: building associated VariantDir targets: build
g++ -o build/src/galapix/workspace.o -c -std=c++11 -O3 -s -isystem/usr/include/libpng12 -isystem/usr/include/SDL2 -fopenmp -isystem/usr/include/x86_64-linux-gnu//Imag
eMagick-6 -isystem/usr/include/ImageMagick-6 -DHAVE_SPACE_NAVIGATOR=1 -D_REENTRANT -DMAGICKCORE_HDRI_ENABLE=0 -DMAGICKCORE_QUANTUM_DEPTH=16 -Ibuild/src -Isrc src/gala
pix/workspace.cpp
src/galapix/workspace.cpp: In member function 'Rectf Workspace::get_bounding_rect() const':
src/galapix/workspace.cpp:474:32: error: 'isnan' was not declared in this scope
if (isnan(image_rect.left) ||
^
src/galapix/workspace.cpp:474:32: note: suggested alternative:
In file included from /usr/include/c++/5/random:38:0,
from /usr/include/c++/5/bits/stl_algo.h:66,
from /usr/include/c++/5/algorithm:62,
from src/galapix/workspace.cpp:21:
/usr/include/c++/5/cmath:641:5: note: 'std::isnan'
isnan(_Tp __x)
^
scons: *** [build/src/galapix/workspace.o] Error 1
scons: building terminated because of errors.
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I fixed it simply by changing "isnan" to "std::isnan" in 4 places inside /src/galapix/workspace.cpp .