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| author | Bruno Haible <bruno@clisp.org> | 2010-12-21 18:55:59 +0100 |
|---|---|---|
| committer | Bruno Haible <bruno@clisp.org> | 2010-12-21 22:49:36 +0100 |
| commit | 9b144e908f361bc95b309fd33bfa0bc09ae55cc7 (patch) | |
| tree | 88832f347ed85acd0a4f35e2de2077e37aae452c /m4/round.m4 | |
| parent | 0c5e7922f80eae16b5a89233d5a8c0d1f88c18a7 (diff) | |
| download | gnulib-9b144e908f361bc95b309fd33bfa0bc09ae55cc7.tar.gz | |
New module 'round-ieee'.
* modules/round-ieee: New file.
* m4/round.m4 (gl_FUNC_ROUND): If gl_FUNC_ROUND_IEEE is also used, test
whether round works according to ISO C 99 with IEC 60559.
* m4/round-ieee.m4: New file.
* modules/round-ieee-tests: New file.
* tests/test-round-ieee.c: New file, based on tests/test-roundf-ieee.c.
* tests/test-round1.c (main): Remove signbit tests.
* modules/round-tests (Depends-on): Remove 'signbit'.
* doc/posix-functions/round.texi: Mention the new module.
Diffstat (limited to 'm4/round.m4')
| -rw-r--r-- | m4/round.m4 | 37 |
1 files changed, 36 insertions, 1 deletions
diff --git a/m4/round.m4 b/m4/round.m4 index 1d1b91c1a1..5f19c5aa68 100644 --- a/m4/round.m4 +++ b/m4/round.m4 @@ -1,4 +1,4 @@ -# round.m4 serial 9 +# round.m4 serial 10 dnl Copyright (C) 2007, 2009-2010 Free Software Foundation, Inc. dnl This file is free software; the Free Software Foundation dnl gives unlimited permission to copy and/or distribute it, @@ -6,6 +6,7 @@ dnl with or without modifications, as long as this notice is preserved. AC_DEFUN([gl_FUNC_ROUND], [ + m4_divert_text([DEFAULTS], [gl_round_required=plain]) AC_REQUIRE([gl_MATH_H_DEFAULTS]) dnl Persuade glibc <math.h> to declare round(). AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) @@ -53,6 +54,40 @@ int main() if test "$ROUND_LIBM" = missing; then REPLACE_ROUND=1 fi + m4_ifdef([gl_FUNC_ROUND_IEEE], [ + if test $gl_round_required = ieee && test $REPLACE_ROUND = 0; then + AC_CACHE_CHECK([whether round works according to ISO C 99 with IEC 60559], + [gl_cv_func_round_ieee], + [ + save_LIBS="$LIBS" + LIBS="$LIBS $ROUND_LIBM" + AC_RUN_IFELSE( + [AC_LANG_SOURCE([[ +#ifndef __NO_MATH_INLINES +# define __NO_MATH_INLINES 1 /* for glibc */ +#endif +#include <math.h> +]gl_DOUBLE_MINUS_ZERO_CODE[ +]gl_DOUBLE_SIGNBIT_CODE[ +int main() +{ + /* Test whether round (-0.0) is -0.0. */ + if (signbitd (minus_zerod) && !signbitd (round (minus_zerod))) + return 1; + return 0; +} + ]])], + [gl_cv_func_round_ieee=yes], + [gl_cv_func_round_ieee=no], + [gl_cv_func_round_ieee="guessing no"]) + LIBS="$save_LIBS" + ]) + case "$gl_cv_func_round_ieee" in + *yes) ;; + *) REPLACE_ROUND=1 ;; + esac + fi + ]) else HAVE_DECL_ROUND=0 fi |