1 files changed, 87 insertions, 5 deletions
diff --git a/libstdc++-v3/include/c/std_cmath.h b/libstdc++-v3/include/c/std_cmath.h
index 2625eac91fb..beb7141625c 100644
--- a/libstdc++-v3/include/c/std_cmath.h
+++ b/libstdc++-v3/include/c/std_cmath.h
@@ -1,6 +1,6 @@
-// -*- C++ -*- C math library.
+// -*- C++ -*- forwarding header.
 
-// Copyright (C) 2000 Free Software Foundation, Inc.
+// Copyright (C) 2000, 2002 Free Software Foundation, Inc.
 //
 // This file is part of the GNU ISO C++ Library.  This library is free
 // software; you can redistribute it and/or modify it under the
@@ -31,12 +31,94 @@
 // ISO C++ 14882: 26.5  C library
 //
 
-// Note: This is not a conforming implementation.
-
 #ifndef _CPP_CMATH
 #define _CPP_CMATH 1
  
 #pragma GCC system_header
-#include <math.h>
 
+#include <bits/c++config.h>
+
+#include_next <math.h>
+
+// Get rid of those macros defined in <math.h> in lieu of real functions.
+#undef abs
+#undef div
+#undef acos
+#undef asin
+#undef atan
+#undef atan2
+#undef ceil
+#undef cos
+#undef cosh
+#undef exp
+#undef fabs
+#undef floor
+#undef fmod
+#undef frexp
+#undef ldexp
+#undef log
+#undef log10
+#undef modf
+#undef pow
+#undef sin
+#undef sinh
+#undef sqrt
+#undef tan
+#undef tanh
+
+#undef fpclassify
+#undef isfinite
+#undef isinf
+#undef isnan
+#undef isnormal
+#undef signbit
+#undef isgreater
+#undef isgreaterequal
+#undef isless
+#undef islessequal
+#undef islessgreater
+#undef isunordered
+
+namespace std 
+{
+  inline double
+  abs(double __x)
+  { return __builtin_fabs(__x); }
+
+  inline float
+  abs(float __x)
+  { return __builtin_fabsf(__x); }
+
+  inline long double
+  abs(long double __x)
+  { return __builtin_fabsl(__x); }
+
+#if _GLIBCPP_HAVE_MODFF
+  inline float 
+  modf(float __x, float* __iptr) { return modff(__x, __iptr); }
+#else
+  inline float 
+  modf(float __x, float* __iptr)
+  {
+    double __tmp;
+    double __res = modf(static_cast<double>(__x), &__tmp);
+    *__iptr = static_cast<float>(__tmp);
+    return __res;
+  }
+#endif
+
+#if _GLIBCPP_HAVE_MODFL
+  inline long double 
+  modf(long double __x, long double* __iptr) { return modfl(__x, __iptr); }
+#else
+  inline long double 
+  modf(long double __x, long double* __iptr) 
+  { 
+    double __tmp;
+    double __res = modf(static_cast<double>(__x), &__tmp);
+    * __iptr = static_cast<long double>(__tmp);
+    return __res;
+  }
+#endif
+}
 #endif