Using the GNU libstdc++ or Clang's libc++ implementations of the
standard library, <cmath> inclusion undefines the isfinite macro,
resulting in compilation errors when wxFinite() is used. <cmath> can be
included unintentionally, e.g. wx/hashmap.h may result in its inclusion
when using STD containers.
Work around this mess by checking if one of these <cmath>
implementations were already included and using std::isfinite() in that
case.
git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@74456 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775
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