new module 'fabsf'

[Bruno Haible]

For 22 <math.h> functions that ought to take 'float' arguments and
return a 'float' result, MSVC 9 only provides a macro definition.
This is not POSIX compliant, see POSIX:2008 / System Interfaces /
General Information / Use and Implementation of Interfaces
<http://pubs.opengroup.org/onlinepubs/9699919799/functions/V2_chap02.html>
section 2.1.1, point 2.

For 'floorf' and 'ceilf', gnulib already fixes this. But not for the 20
others. Let me handle them one by one.

Here's the module for 'fabsf'.


2011-10-05  Bruno Haible  <address@hidden>

        New module 'fabsf'.
        * lib/math.in.h (fabsf): New declaration.
        * lib/fabsf.c: New file.
        * m4/fabsf.m4: New file.
        * m4/math_h.m4 (gl_MATH_H_DEFAULTS): Initialize GNULIB_FABSF,
        HAVE_FABSF.
        * modules/math (Makefile.am): Substitute GNULIB_FABSF, HAVE_FABSF.
        * modules/fabsf: New file.
        * tests/test-math-c++.cc: Check the declaration of fabsf.
        * doc/posix-functions/fabsf.texi: Mention the new module.

================================= lib/fabsf.c =================================
/* Absolute value.
   Copyright (C) 2011 Free Software Foundation, Inc.

   This program is free software: you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include <config.h>

/* Specification.  */
#include <math.h>

float
fabsf (float x)
{
  return (float) fabs ((double) x);
}
================================= m4/fabsf.m4 =================================
# fabsf.m4 serial 1
dnl Copyright (C) 2011 Free Software Foundation, Inc.
dnl This file is free software; the Free Software Foundation
dnl gives unlimited permission to copy and/or distribute it,
dnl with or without modifications, as long as this notice is preserved.

AC_DEFUN([gl_FUNC_FABSF],
[
  AC_REQUIRE([gl_MATH_H_DEFAULTS])
  AC_REQUIRE([gl_FUNC_FABS])

  dnl Test whether fabsf() exists. Assume that fabsf(), if it exists, is
  dnl defined in the same library as fabs().
  save_LIBS="$LIBS"
  LIBS="$LIBS $FABS_LIBM"
  AC_CHECK_FUNCS([fabsf])
  LIBS="$save_LIBS"
  if test $ac_cv_func_fabsf = yes; then
    FABSF_LIBM="$FABS_LIBM"
  else
    HAVE_FABSF=0
    FABSF_LIBM="$FABS_LIBM"
  fi
  AC_SUBST([FABSF_LIBM])
])
================================ modules/fabsf ================================
Description:
fabsf() function: absolute value.

Files:
lib/fabsf.c
m4/fabsf.m4

Depends-on:
math
fabs            [test $HAVE_FABSF = 0]

configure.ac:
gl_FUNC_FABSF
if test $HAVE_FABSF = 0; then
  AC_LIBOBJ([fabsf])
fi
gl_MATH_MODULE_INDICATOR([fabsf])

Makefile.am:

Include:
<math.h>

Link:
$(FABSF_LIBM)

License:
LGPL

Maintainer:
Bruno Haible
===============================================================================
--- doc/posix-functions/fabsf.texi.orig Wed Oct  5 23:56:39 2011
+++ doc/posix-functions/fabsf.texi      Wed Oct  5 22:24:13 2011
@@ -4,14 +4,10 @@
 
 POSIX specification:@* 
@url{http://www.opengroup.org/onlinepubs/9699919799/functions/fabsf.html}
 
-Gnulib module: ---
+Gnulib module: fabsf
 
 Portability problems fixed by Gnulib:
 @itemize
address@hidden itemize
-
-Portability problems not fixed by Gnulib:
address@hidden
 @item
 This function is missing on some platforms:
 AIX 5.1, Solaris 9.
@@ -19,3 +15,7 @@
 This function is only defined as a macro with arguments on some platforms:
 MSVC 9.
 @end itemize
+
+Portability problems not fixed by Gnulib:
address@hidden
address@hidden itemize
--- lib/math.in.h.orig  Wed Oct  5 23:56:39 2011
+++ lib/math.in.h       Wed Oct  5 23:14:07 2011
@@ -282,6 +282,22 @@
 #endif
 
 
+#if @GNULIB_FABSF@
+# if address@hidden@
+#  undef fabsf
+_GL_FUNCDECL_SYS (fabsf, float, (float x));
+# endif
+_GL_CXXALIAS_SYS (fabsf, float, (float x));
+_GL_CXXALIASWARN (fabsf);
+#elif defined GNULIB_POSIXCHECK
+# undef fabsf
+# if HAVE_RAW_DECL_FABSF
+_GL_WARN_ON_USE (fabsf, "fabsf is unportable - "
+                 "use gnulib module fabsf for portability");
+# endif
+#endif
+
+
 #if @GNULIB_FLOORF@
 # if @REPLACE_FLOORF@
 #  if !(defined __cplusplus && defined GNULIB_NAMESPACE)
--- m4/math_h.m4.orig   Wed Oct  5 23:56:39 2011
+++ m4/math_h.m4        Wed Oct  5 22:32:08 2011
@@ -1,4 +1,4 @@
-# math_h.m4 serial 25
+# math_h.m4 serial 26
 dnl Copyright (C) 2007-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -62,6 +62,7 @@
   GNULIB_CEILL=0;    AC_SUBST([GNULIB_CEILL])
   GNULIB_COSL=0;     AC_SUBST([GNULIB_COSL])
   GNULIB_EXPL=0;     AC_SUBST([GNULIB_EXPL])
+  GNULIB_FABSF=0;    AC_SUBST([GNULIB_FABSF])
   GNULIB_FLOOR=0;    AC_SUBST([GNULIB_FLOOR])
   GNULIB_FLOORF=0;   AC_SUBST([GNULIB_FLOORF])
   GNULIB_FLOORL=0;   AC_SUBST([GNULIB_FLOORL])
@@ -92,6 +93,7 @@
   HAVE_ATANL=1;                AC_SUBST([HAVE_ATANL])
   HAVE_COSL=1;                 AC_SUBST([HAVE_COSL])
   HAVE_EXPL=1;                 AC_SUBST([HAVE_EXPL])
+  HAVE_FABSF=1;                AC_SUBST([HAVE_FABSF])
   HAVE_ISNANF=1;               AC_SUBST([HAVE_ISNANF])
   HAVE_ISNAND=1;               AC_SUBST([HAVE_ISNAND])
   HAVE_ISNANL=1;               AC_SUBST([HAVE_ISNANL])
--- modules/math.orig   Wed Oct  5 23:56:39 2011
+++ modules/math        Wed Oct  5 22:28:26 2011
@@ -36,6 +36,7 @@
              -e 's/@''GNULIB_CEILL''@/$(GNULIB_CEILL)/g' \
              -e 's/@''GNULIB_COSL''@/$(GNULIB_COSL)/g' \
              -e 's/@''GNULIB_EXPL''@/$(GNULIB_EXPL)/g' \
+             -e 's/@''GNULIB_FABSF''@/$(GNULIB_FABSF)/g' \
              -e 's/@''GNULIB_FLOOR''@/$(GNULIB_FLOOR)/g' \
              -e 's/@''GNULIB_FLOORF''@/$(GNULIB_FLOORF)/g' \
              -e 's/@''GNULIB_FLOORL''@/$(GNULIB_FLOORL)/g' \
@@ -66,6 +67,7 @@
              -e 's|@''HAVE_ATANL''@|$(HAVE_ATANL)|g' \
              -e 's|@''HAVE_COSL''@|$(HAVE_COSL)|g' \
              -e 's|@''HAVE_EXPL''@|$(HAVE_EXPL)|g' \
+             -e 's|@''HAVE_FABSF''@|$(HAVE_FABSF)|g' \
              -e 's|@''HAVE_ISNANF''@|$(HAVE_ISNANF)|g' \
              -e 's|@''HAVE_ISNAND''@|$(HAVE_ISNAND)|g' \
              -e 's|@''HAVE_ISNANL''@|$(HAVE_ISNANL)|g' \
--- tests/test-math-c++.cc.orig Wed Oct  5 23:56:39 2011
+++ tests/test-math-c++.cc      Wed Oct  5 22:31:04 2011
@@ -35,6 +35,9 @@
 //SIGNATURE_CHECK (GNULIB_NAMESPACE::erf, double, (double));
 //SIGNATURE_CHECK (GNULIB_NAMESPACE::erfc, double, (double));
 //SIGNATURE_CHECK (GNULIB_NAMESPACE::exp, double, (double));
+#if GNULIB_TEST_FABSF
+SIGNATURE_CHECK (GNULIB_NAMESPACE::fabsf, float, (float));
+#endif
 //SIGNATURE_CHECK (GNULIB_NAMESPACE::fabs, double, (double));
 //SIGNATURE_CHECK (GNULIB_NAMESPACE::fmod, double, (double, double));
 #if GNULIB_TEST_FREXP

-- 
In memoriam Annalena Tonelli <http://en.wikipedia.org/wiki/Annalena_Tonelli>