Add missing long double functions to Cygwin

This patch adds the long double functions missing in newlib to Cygwin.
Apart from some self-written additions (exp10l, finite{f,l}, isinf{f,l},
isnan{f,l}, pow10l) the files are taken from the Mingw-w64 math lib.
Minor changes were required, e.g. substitue _WIN64 with __x86_64__ and
fixing __FLT_RPT_DOMAIN/__FLT_RPT_ERANGE for Cygwin.

Cygwin:
	* math: New subdir with math functions.
	* Makefile.in (VPATH): Add math subdir.
	(MATH_OFILES): List of object files collected from building files in
	math subdir.
	(DLL_OFILES): Add $(MATH_OFILES).
	${CURDIR}/libm.a: Add $(MATH_OFILES) to build.
	* common.din: Add new functions from math subdir.
	* i686.din: Align to new math subdir.  Remove functions now commonly
	available.
	* x86_64.din: Ditto.
	* math.h: math.h wrapper to define mingw structs used in some files in
	math subdir.
	* include/cygwin/version.h: Bump API minor version.

newlib:
	* libc/include/complex.h: Add prototypes for complex long double
	functions.  Only define for Cygwin.
	* libc/include/math.h: Additionally enable prototypes of long double
	functions for Cygwin.  Add Cygwin-only prototypes for dreml, sincosl,
	exp10l and pow10l.  Explain why we don't add them to newlib.
	* libc/include/tgmath.h: Enable long double handling on Cygwin.

Signed-off-by: Corinna Vinschen <corinna@vinschen.de>

1 files changed, 45 insertions, 0 deletions

diff --git a/winsup/cygwin/math/coshl.c b/winsup/cygwin/math/coshl.c
new file mode 100644
index 000000000..d7eb4b7cb
--- /dev/null
+++ b/winsup/cygwin/math/coshl.c
@@ -0,0 +1,45 @@
+/**
+ * This file has no copyright assigned and is placed in the Public Domain.
+ * This file is part of the mingw-w64 runtime package.
+ * No warranty is given; refer to the file DISCLAIMER.PD within this package.
+ */
+#include "cephes_mconf.h"
+
+#ifndef _SET_ERRNO
+#define _SET_ERRNO(x)
+#endif
+
+long double coshl(long double x)
+{
+  long double y;
+  int x_class = fpclassify (x);
+  if (x_class == FP_NAN)
+    {
+      errno = EDOM;
+      return x;
+    }
+  else if (x_class == FP_INFINITE)
+    {
+       errno = ERANGE;
+       return x;
+    }
+  x = fabsl (x);
+  if (x > (MAXLOGL + LOGE2L))
+    {
+      errno = ERANGE;
+#ifdef INFINITIES
+      return (INFINITYL);
+#else
+      return (MAXNUML);
+#endif
+    }
+  if (x >= (MAXLOGL - LOGE2L))
+    {
+      y = expl(0.5L * x);
+      y = (0.5L * y) * y;
+      return y;
+    }
+  y = expl(x);
+  y = 0.5L * (y + 1.0L / y);
+  return y;
+}