math-undefs.h was introduced to keep Coin developers from using floating point versions of math functions for portability reasons (e.g. cosf). However, those floating point functions are now used in header files of the compiler infrastructure. Simply undefining them causes problems with newer compilers. A check has already been added to not undefine the float versions of these functions when clang is used, which fixed compilation issues on OS X. Now I run into the same issue with Visual Studio 2015 compiler. I therefore propose to remove this include file. The reviews for commits to this repository are rigor and we should be able to catch the usage of floating point math functions then.
A work-around for VS2015 builds is to disable this include file via CMake command line option: -DCMAKE_CXX_FLAGS=/DCOIN_MATH_UNDEFS_H