Update.

1998-07-29  Andreas Jaeger  <aj@arthur.rhein-neckar.de>

	* manual/pattern.texi (More Flags for Globbing): Fix typo.

	* manual/math.texi (Special Functions): Fix typo.

	* sysdeps/unix/sysv/linux/bits/in.h (IPV6_ROUTER_ALERT): New
	constant from Linux 2.1.112.

	* posix/Makefile (install-lib): Compile libposix.a only if
	build-static == yes.

1998-07-28  Andreas Schwab  <schwab@issan.informatik.uni-dortmund.de>

	* sysdeps/generic/glob.c: Maintain const correctness.  Move extern
	declarations to file level.  Cope with unsupported
	_SC_GETPW_R_SIZE_MAX.

1998-07-29  Ulrich Drepper  <drepper@cygnus.com>

	* stdio-common/tst-printf.c: %z is now recognized by printf.

	* sysdeps/libm-ieee754/c_csqrt.c: Fix problems with some cancelation
	errors.
	* sysdeps/libm-ieee754/c_csqrtf.c: Likewise.
	* sysdeps/libm-ieee754/c_csqrtlc: Likewise.
	Patch by Stephen L Moshier <moshier@mediaone.net>.

	* math/libm-test.c (csqrt_test): Correct typo in one test, add
	another one.

	* sysdeps/unix/sysv/linux/bits/siginfo.h: Adjust siginfo_t after
	latest kernel change.

3 files changed, 51 insertions, 42 deletions

diff --git a/sysdeps/libm-ieee754/s_csqrt.c b/sysdeps/libm-ieee754/s_csqrt.c
index cda23c702d..ae106bdad8 100644
--- a/sysdeps/libm-ieee754/s_csqrt.c
+++ b/sysdeps/libm-ieee754/s_csqrt.c
@@ -1,5 +1,5 @@
 /* Complex square root of double value.
-   Copyright (C) 1997 Free Software Foundation, Inc.
+   Copyright (C) 1997, 1998 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Based on an algorithm by Stephen L. Moshier <moshier@world.std.com>.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
@@ -84,22 +84,25 @@ __csqrt (__complex__ double x)
 	}
       else
 	{
-#if 0 /* FIXME: this is broken. */
-	  __complex__ double q;
-	  double t, r;
+#if 0
+	  double d, r, s;
 
-	  if (fabs (__imag__ x) < 2.0e-4 * fabs (__real__ x))
-	    t = 0.25 * __imag__ x * (__imag__ x / __real__ x);
+	  d = __ieee754_hypot (__real__ x, __imag__ x);
+	  /* Use the identity   2  Re res  Im res = Im x
+	     to avoid cancellation error in  d +/- Re x.  */
+	  if (__real__ x > 0)
+	    {
+	      r = __ieee754_sqrt (0.5 * d + 0.5 * __real__ x);
+	      s = (0.5 * __imag__ x) / r;
+	    }
 	  else
-	    t = 0.5 * (__ieee754_hypot (__real__ x, __imag__ x) - __real__ x);
-
-	  r = __ieee754_sqrt (t);
-
-	  __real__ q = __imag__ x / (2.0 * r);
-	  __imag__ q = r;
+	    {
+	      s = __ieee754_sqrt (0.5 * d - 0.5 * __real__ x);
+	      r = (0.5 * __imag__ x) / s;
+	    }
 
-	  /* Heron iteration in complex arithmetic.  */
-	  res = 0.5 * (q + q / x);
+	  __real__ res = r;
+	  __imag__ res = __copysign (s, __imag__ x);
 #else
 	  double d, imag;
 
diff --git a/sysdeps/libm-ieee754/s_csqrtf.c b/sysdeps/libm-ieee754/s_csqrtf.c
index 5fdf2c1d66..015b0cd57f 100644
--- a/sysdeps/libm-ieee754/s_csqrtf.c
+++ b/sysdeps/libm-ieee754/s_csqrtf.c
@@ -1,5 +1,5 @@
 /* Complex square root of float value.
-   Copyright (C) 1997 Free Software Foundation, Inc.
+   Copyright (C) 1997, 1998 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Based on an algorithm by Stephen L. Moshier <moshier@world.std.com>.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
@@ -84,22 +84,25 @@ __csqrtf (__complex__ float x)
 	}
       else
 	{
-#if 0 /* FIXME: this is broken. */
-	  __complex__ float q;
-	  float t, r;
+#if 0
+	  float d, r, s;
 
-	  if (fabsf (__imag__ x) < 2.0e-4 * fabsf (__real__ x))
-	    t = 0.25 * __imag__ x * (__imag__ x / __real__ x);
+	  d = __ieee754_hypotf (__real__ x, __imag__ x);
+	  /* Use the identity   2  Re res  Im res = Im x
+	     to avoid cancellation error in  d +/- Re x.  */
+	  if (__real__ x > 0)
+	    {
+	      r = __ieee754_sqrtf (0.5f * d + 0.5f * __real__ x);
+	      s = (0.5f * __imag__ x) / r;
+	    }
 	  else
-	    t = 0.5 * (__ieee754_hypotf (__real__ x, __imag__ x) - __real__ x);
-
-	  r = __ieee754_sqrtf (t);
-
-	  __real__ q = __imag__ x / (2.0 * r);
-	  __imag__ q = r;
+	    {
+	      s = __ieee754_sqrtf (0.5f * d - 0.5f * __real__ x);
+	      r = (0.5f * __imag__ x) / s;
+	    }
 
-	  /* Heron iteration in complex arithmetic.  */
-	  res = 0.5 * (q + q / x);
+	  __real__ res = r;
+	  __imag__ res = __copysignf (s, __imag__ x);
 #else
 	  float d, imag;
 
diff --git a/sysdeps/libm-ieee754/s_csqrtl.c b/sysdeps/libm-ieee754/s_csqrtl.c
index b772709947..4b7ed983d8 100644
--- a/sysdeps/libm-ieee754/s_csqrtl.c
+++ b/sysdeps/libm-ieee754/s_csqrtl.c
@@ -1,5 +1,5 @@
 /* Complex square root of long double value.
-   Copyright (C) 1997 Free Software Foundation, Inc.
+   Copyright (C) 1997, 1998 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Based on an algorithm by Stephen L. Moshier <moshier@world.std.com>.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1997.
@@ -84,22 +84,25 @@ __csqrtl (__complex__ long double x)
 	}
       else
 	{
-#if 0 /* FIXME: this is broken. */
-	  __complex__ long double q;
-	  long double t, r;
+#if 0
+	  long double d, r, s;
 
-	  if (fabsl (__imag__ x) < 2.0e-4 * fabsl (__real__ x))
-	    t = 0.25 * __imag__ x * (__imag__ x / __real__ x);
+	  d = __ieee754_hypotl (__real__ x, __imag__ x);
+	  /* Use the identity   2  Re res  Im res = Im x
+	     to avoid cancellation error in  d +/- Re x.  */
+	  if (__real__ x > 0)
+	    {
+	      r = __ieee754_sqrtl (0.5L * d + 0.5L * __real__ x);
+	      s = (0.5L * __imag__ x) / r;
+	    }
 	  else
-	    t = 0.5 * (__ieee754_hypotl (__real__ x, __imag__ x) - __real__ x);
-
-	  r = __ieee754_sqrtl (t);
-
-	  __real__ q = __imag__ x / (2.0 * r);
-	  __imag__ q = r;
+	    {
+	      s = __ieee754_sqrtl (0.5L * d - 0.5L * __real__ x);
+	      r = (0.5L * __imag__ x) / s;
+	    }
 
-	  /* Heron iteration in complex arithmetic.  */
-	  res = 0.5 * (q + q / x);
+	  __real__ res = r;
+	  __imag__ res = __copysignl (s, __imag__ x);
 #else
 	  long double d, imag;