Determining size of long double passed with the following output:
Change Dir: '/home/juli/Matlab/scctools/ports/c_symb/symengine/build_wasm/CMakeFiles/CMakeTmp'

Run Build Command(s): /usr/bin/cmake -E env VERBOSE=1 /usr/bin/make -f Makefile cmTC_300d7/fast
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make[1]: Entering directory '/home/juli/Matlab/scctools/ports/c_symb/symengine/build_wasm/CMakeFiles/CMakeTmp'
Building C object CMakeFiles/cmTC_300d7.dir/SYMENGINE_SIZEOF_LONG_DOUBLE.c.o
/usr/lib/emsdk/upstream/emscripten/emcc    -MD -MT CMakeFiles/cmTC_300d7.dir/SYMENGINE_SIZEOF_LONG_DOUBLE.c.o -MF CMakeFiles/cmTC_300d7.dir/SYMENGINE_SIZEOF_LONG_DOUBLE.c.o.d -o CMakeFiles/cmTC_300d7.dir/SYMENGINE_SIZEOF_LONG_DOUBLE.c.o -c /home/juli/Matlab/scctools/ports/c_symb/symengine/build_wasm/CMakeFiles/CheckTypeSize/SYMENGINE_SIZEOF_LONG_DOUBLE.c
Linking C executable cmTC_300d7.js
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/usr/lib/emsdk/upstream/emscripten/emcc @CMakeFiles/cmTC_300d7.dir/objects1.rsp -o cmTC_300d7.js @CMakeFiles/cmTC_300d7.dir/linkLibs.rsp
make[1]: Leaving directory '/home/juli/Matlab/scctools/ports/c_symb/symengine/build_wasm/CMakeFiles/CMakeTmp'