1 files changed, 66 insertions, 0 deletions
diff --git a/winsup/mingw/mingwex/complex/cacosl.c b/winsup/mingw/mingwex/complex/cacosl.c
new file mode 100755
index 000000000..c8e0b6eda
--- /dev/null
+++ b/winsup/mingw/mingwex/complex/cacosl.c
@@ -0,0 +1,66 @@
+/*
+   cacosl.c
+   Contributed by Danny Smith
+   2004-01-04
+*/
+
+#include <math.h>
+#include <complex.h>
+
+#if 0
+/* cacos (Z) = -I * clog(Z + I * csqrt(1 - Z * Z)) */
+
+long double complex cacosl (long double  complex Z)
+{
+  long double complex Res;
+  long double x, y;
+
+  x = __real__ Z;
+  y = __imag__ Z;
+
+  if (y == 0.0L)
+    {
+      __real__ Res = acosl (x);
+      __imag__ Res = 0.0L;
+    }
+
+  else
+    {
+      long double complex ZZ;
+      /* Z * Z = ((x - y) * (x + y)) + (2.0 * x * y) * I */
+      /* caculate 1 - Z * Z */
+      __real__ ZZ = 1.0L - (x - y) * (x + y);
+      __imag__ ZZ = -2.0L * x * y;
+
+       
+       Res = csqrtl(ZZ);
+
+      /* calculate ZZ + I * sqrt (ZZ) */
+    
+      __real__ ZZ = x - __imag__ Res;
+      __imag__ ZZ = y + __real__ Res;
+       
+      ZZ = clogl(ZZ);
+
+      /* mult by -I */
+
+      __real__ Res  =  __imag__ ZZ;
+      __imag__ Res = - __real__ ZZ;
+    }
+  return Res;
+}
+
+#else
+
+/* cacos ( Z ) =  pi/2 - casin ( Z ) */
+#ifndef _M_PI_2L
+#define _M_PI_2L 1.5707963267948966192313L
+#endif
+long double complex cacosl (long double complex Z)
+{
+  long double complex Res  = casinl (Z);
+  __real__ Res = _M_PI_2L - __real__ Res;
+  __imag__ Res = - __imag__ Res;
+  return Res;
+}
+#endif