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Date: Fri, 19 May 2006 17:08:18 +0200
From: Andrea Venturoli <ml@netfence.it>
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Subject: Loop in cmath
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Hello.

This is on a 5.4p13 i386 box; from /usr/include/c++/3.4/cmath:

...
#if _GLIBCXX_USE_C99_MATH
#if !_GLIBCXX_USE_C99_FP_MACROS_DYNAMIC
namespace __gnu_cxx
{
...
   template<typename _Tp>
     int
     __capture_isnan(_Tp __f) { return isnan(__f); }
...
}
...
#undef isnan
...
#endif /* _GLIBCXX_USE_C99_FP_MACROS_DYNAMIC */
#endif

#if _GLIBCXX_USE_C99_MATH
#if !_GLIBCXX_USE_C99_FP_MACROS_DYNAMIC
namespace __gnu_cxx
{
...
   template<typename _Tp>
     int
     isnan(_Tp __f) { return __capture_isnan(__f); }
...
}

namespace std
{
...
   using __gnu_cxx::isnan;
}
#endif /* _GLIBCXX_USE_C99_FP_MACROS_DYNAMIC */
#endif





This results in any call to std::isnan looping thorugh the two above 
functions.

Is this a bug? Should any macro be defined to avoid this?

  bye & Thanks
	av.