Mercurial > gnulib
view m4/floor.m4 @ 40057:b06060465f09
maint: Run 'make update-copyright'
author | Paul Eggert <eggert@cs.ucla.edu> |
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date | Tue, 01 Jan 2019 00:25:11 +0100 |
parents | 062361de7628 |
children | e2e6dc79463b |
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# floor.m4 serial 11 dnl Copyright (C) 2007, 2009-2019 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_FLOOR], [ m4_divert_text([DEFAULTS], [gl_floor_required=plain]) AC_REQUIRE([gl_MATH_H_DEFAULTS]) dnl Test whether floor() can be used without libm. gl_FUNC_FLOOR_LIBS if test "$FLOOR_LIBM" = "?"; then FLOOR_LIBM= fi m4_ifdef([gl_FUNC_FLOOR_IEEE], [ if test $gl_floor_required = ieee && test $REPLACE_FLOOR = 0; then AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles AC_CACHE_CHECK([whether floor works according to ISO C 99 with IEC 60559], [gl_cv_func_floor_ieee], [ save_LIBS="$LIBS" LIBS="$LIBS $FLOOR_LIBM" AC_RUN_IFELSE( [AC_LANG_SOURCE([[ #ifndef __NO_MATH_INLINES # define __NO_MATH_INLINES 1 /* for glibc */ #endif #include <math.h> ]gl_DOUBLE_MINUS_ZERO_CODE[ ]gl_DOUBLE_SIGNBIT_CODE[ static double dummy (double f) { return 0; } int main (int argc, char *argv[]) { double (*my_floor) (double) = argc ? floor : dummy; /* Test whether floor (-0.0) is -0.0. */ if (signbitd (minus_zerod) && !signbitd (my_floor (minus_zerod))) return 1; return 0; } ]])], [gl_cv_func_floor_ieee=yes], [gl_cv_func_floor_ieee=no], [case "$host_os" in # Guess yes on glibc systems. *-gnu* | gnu*) gl_cv_func_floor_ieee="guessing yes" ;; # Guess yes on native Windows. mingw*) gl_cv_func_floor_ieee="guessing yes" ;; # If we don't know, assume the worst. *) gl_cv_func_floor_ieee="guessing no" ;; esac ]) LIBS="$save_LIBS" ]) case "$gl_cv_func_floor_ieee" in *yes) ;; *) REPLACE_FLOOR=1 ;; esac fi ]) if test $REPLACE_FLOOR = 1; then dnl No libraries are needed to link lib/floor.c. FLOOR_LIBM= fi AC_SUBST([FLOOR_LIBM]) ]) # Determines the libraries needed to get the floor() function. # Sets FLOOR_LIBM. AC_DEFUN([gl_FUNC_FLOOR_LIBS], [ gl_CACHE_VAL_SILENT([gl_cv_func_floor_libm], [ gl_cv_func_floor_libm=? AC_LINK_IFELSE( [AC_LANG_PROGRAM( [[#ifndef __NO_MATH_INLINES # define __NO_MATH_INLINES 1 /* for glibc */ #endif #include <math.h> double (*funcptr) (double) = floor; double x;]], [[x = funcptr(x) + floor(x);]])], [gl_cv_func_floor_libm=]) if test "$gl_cv_func_floor_libm" = "?"; then save_LIBS="$LIBS" LIBS="$LIBS -lm" AC_LINK_IFELSE( [AC_LANG_PROGRAM( [[#ifndef __NO_MATH_INLINES # define __NO_MATH_INLINES 1 /* for glibc */ #endif #include <math.h> double (*funcptr) (double) = floor; double x;]], [[x = funcptr(x) + floor(x);]])], [gl_cv_func_floor_libm="-lm"]) LIBS="$save_LIBS" fi ]) FLOOR_LIBM="$gl_cv_func_floor_libm" ])