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Diffstat (limited to 'gnulib/m4/round.m4')
| m--------- | gnulib | 0 | ||||
| -rw-r--r-- | gnulib/m4/round.m4 | 113 |
2 files changed, 113 insertions, 0 deletions
diff --git a/gnulib b/gnulib deleted file mode 160000 -Subproject 443bc5ffcf7429e557f4a371b0661abe98ddbc1 diff --git a/gnulib/m4/round.m4 b/gnulib/m4/round.m4 new file mode 100644 index 0000000..e64208e --- /dev/null +++ b/gnulib/m4/round.m4 @@ -0,0 +1,113 @@ +# round.m4 serial 13 +dnl Copyright (C) 2007, 2009-2011 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_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]) + AC_CHECK_DECLS([round], , , [[#include <math.h>]]) + if test "$ac_cv_have_decl_round" = yes; then + gl_CHECK_MATH_LIB([ROUND_LIBM], [x = round (x);]) + if test "$ROUND_LIBM" != missing; then + dnl Test whether round() produces correct results. On NetBSD 3.0, for + dnl x = 1/2 - 2^-54, the system's round() returns a wrong result. + AC_REQUIRE([AC_PROG_CC]) + AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles + AC_CACHE_CHECK([whether round works], [gl_cv_func_round_works], + [ + save_LIBS="$LIBS" + LIBS="$LIBS $ROUND_LIBM" + AC_RUN_IFELSE([AC_LANG_SOURCE([[ +#include <float.h> +#include <math.h> +int main() +{ + /* 2^DBL_MANT_DIG. */ + static const double TWO_MANT_DIG = + /* Assume DBL_MANT_DIG <= 5 * 31. + Use the identity + n = floor(n/5) + floor((n+1)/5) + ... + floor((n+4)/5). */ + (double) (1U << (DBL_MANT_DIG / 5)) + * (double) (1U << ((DBL_MANT_DIG + 1) / 5)) + * (double) (1U << ((DBL_MANT_DIG + 2) / 5)) + * (double) (1U << ((DBL_MANT_DIG + 3) / 5)) + * (double) (1U << ((DBL_MANT_DIG + 4) / 5)); + volatile double x = 0.5 - 0.5 / TWO_MANT_DIG; + exit (x < 0.5 && round (x) != 0.0); +}]])], [gl_cv_func_round_works=yes], [gl_cv_func_round_works=no], + [case "$host_os" in + netbsd* | aix*) gl_cv_func_round_works="guessing no";; + *) gl_cv_func_round_works="guessing yes";; + esac + ]) + LIBS="$save_LIBS" + ]) + case "$gl_cv_func_round_works" in + *no) ROUND_LIBM=missing ;; + esac + fi + 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 $ROUND_LIBM" + AC_RUN_IFELSE( + [AC_LANG_SOURCE([[ +#ifndef __NO_MATH_INLINES +# define __NO_MATH_INLINES 1 /* for glibc */ +#endif +#include <math.h> +]gl_DOUBLE_MINUS_ZERO_CODE[ +]gl_DOUBLE_SIGNBIT_CODE[ +static double dummy (double f) { return 0; } +int main (int argc, char *argv[]) +{ + double (*my_round) (double) = argc ? round : dummy; + /* Test whether round (-0.0) is -0.0. */ + if (signbitd (minus_zerod) && !signbitd (my_round (minus_zerod))) + return 1; + return 0; +} + ]])], + [gl_cv_func_round_ieee=yes], + [gl_cv_func_round_ieee=no], + [gl_cv_func_round_ieee="guessing no"]) + LIBS="$save_LIBS" + ]) + case "$gl_cv_func_round_ieee" in + *yes) ;; + *) REPLACE_ROUND=1 ;; + esac + fi + ]) + else + HAVE_DECL_ROUND=0 + fi + if test $HAVE_DECL_ROUND = 0 || test $REPLACE_ROUND = 1; then + dnl Find libraries needed to link lib/round.c. + gl_FUNC_FLOOR_LIBS + gl_FUNC_CEIL_LIBS + ROUND_LIBM= + dnl Append $FLOOR_LIBM to ROUND_LIBM, avoiding gratuitous duplicates. + case " $ROUND_LIBM " in + *" $FLOOR_LIBM "*) ;; + *) ROUND_LIBM="$ROUND_LIBM $FLOOR_LIBM" ;; + esac + dnl Append $CEIL_LIBM to ROUND_LIBM, avoiding gratuitous duplicates. + case " $ROUND_LIBM " in + *" $CEIL_LIBM "*) ;; + *) ROUND_LIBM="$ROUND_LIBM $CEIL_LIBM" ;; + esac + fi + AC_SUBST([ROUND_LIBM]) +]) |