| # log10f.m4 serial 12 |
| dnl Copyright (C) 2011-2020 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_LOG10F], |
| [ |
| m4_divert_text([DEFAULTS], [gl_log10f_required=plain]) |
| AC_REQUIRE([gl_MATH_H_DEFAULTS]) |
| AC_REQUIRE([gl_FUNC_LOG10]) |
| |
| dnl Persuade glibc <math.h> to declare log10f(). |
| AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) |
| |
| dnl Test whether log10f() exists. Assume that log10f(), if it exists, is |
| dnl defined in the same library as log10(). |
| save_LIBS="$LIBS" |
| LIBS="$LIBS $LOG10_LIBM" |
| AC_CHECK_FUNCS([log10f]) |
| LIBS="$save_LIBS" |
| if test $ac_cv_func_log10f = yes; then |
| LOG10F_LIBM="$LOG10_LIBM" |
| |
| save_LIBS="$LIBS" |
| LIBS="$LIBS $LOG10F_LIBM" |
| gl_FUNC_LOG10F_WORKS |
| LIBS="$save_LIBS" |
| case "$gl_cv_func_log10f_works" in |
| *yes) ;; |
| *) REPLACE_LOG10F=1 ;; |
| esac |
| |
| m4_ifdef([gl_FUNC_LOG10F_IEEE], [ |
| if test $gl_log10f_required = ieee && test $REPLACE_LOG10F = 0; then |
| AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles |
| AC_CACHE_CHECK([whether log10f works according to ISO C 99 with IEC 60559], |
| [gl_cv_func_log10f_ieee], |
| [ |
| save_LIBS="$LIBS" |
| LIBS="$LIBS $LOG10F_LIBM" |
| AC_RUN_IFELSE( |
| [AC_LANG_SOURCE([[ |
| #ifndef __NO_MATH_INLINES |
| # define __NO_MATH_INLINES 1 /* for glibc */ |
| #endif |
| #include <math.h> |
| /* Compare two numbers with ==. |
| This is a separate function because IRIX 6.5 "cc -O" miscompiles an |
| 'x == x' test. */ |
| static int |
| numeric_equal (float x, float y) |
| { |
| return x == y; |
| } |
| static float dummy (float x) { return 0; } |
| int main (int argc, char *argv[]) |
| { |
| float (* volatile my_log10f) (float) = argc ? log10f : dummy; |
| /* Test log10f(negative). |
| This test fails on NetBSD 5.1. */ |
| float y = my_log10f (-1.0f); |
| if (numeric_equal (y, y)) |
| return 1; |
| return 0; |
| } |
| ]])], |
| [gl_cv_func_log10f_ieee=yes], |
| [gl_cv_func_log10f_ieee=no], |
| [case "$host_os" in |
| # Guess yes on glibc systems. |
| *-gnu* | gnu*) gl_cv_func_log10f_ieee="guessing yes" ;; |
| # Guess yes on musl systems. |
| *-musl*) gl_cv_func_log10f_ieee="guessing yes" ;; |
| # Guess yes on native Windows. |
| mingw*) gl_cv_func_log10f_ieee="guessing yes" ;; |
| # If we don't know, obey --enable-cross-guesses. |
| *) gl_cv_func_log10f_ieee="$gl_cross_guess_normal" ;; |
| esac |
| ]) |
| LIBS="$save_LIBS" |
| ]) |
| case "$gl_cv_func_log10f_ieee" in |
| *yes) ;; |
| *) REPLACE_LOG10F=1 ;; |
| esac |
| fi |
| ]) |
| else |
| HAVE_LOG10F=0 |
| dnl If the function is declared but does not appear to exist, it may be |
| dnl defined as an inline function. In order to avoid a conflict, we have |
| dnl to define rpl_log10f, not log10f. |
| AC_CHECK_DECLS([log10f], [REPLACE_LOG10F=1], , [[#include <math.h>]]) |
| fi |
| if test $HAVE_LOG10F = 0 || test $REPLACE_LOG10F = 1; then |
| dnl Find libraries needed to link lib/log10f.c. |
| if test $HAVE_LOG10F = 0; then |
| LOG10F_LIBM="$LOG10_LIBM" |
| fi |
| fi |
| AC_SUBST([LOG10F_LIBM]) |
| ]) |
| |
| dnl Test whether log10f() works. |
| dnl On OSF/1 5.1, log10f(-0.0f) is NaN. |
| AC_DEFUN([gl_FUNC_LOG10F_WORKS], |
| [ |
| AC_REQUIRE([AC_PROG_CC]) |
| AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles |
| AC_CACHE_CHECK([whether log10f works], [gl_cv_func_log10f_works], |
| [ |
| AC_RUN_IFELSE( |
| [AC_LANG_SOURCE([[ |
| #include <math.h> |
| volatile float x; |
| float y; |
| int main () |
| { |
| x = -0.0f; |
| y = log10f (x); |
| if (!(y + y == y)) |
| return 1; |
| return 0; |
| } |
| ]])], |
| [gl_cv_func_log10f_works=yes], |
| [gl_cv_func_log10f_works=no], |
| [case "$host_os" in |
| osf*) gl_cv_func_log10f_works="guessing no" ;; |
| # Guess yes on native Windows. |
| mingw*) gl_cv_func_log10f_works="guessing yes" ;; |
| *) gl_cv_func_log10f_works="guessing yes" ;; |
| esac |
| ]) |
| ]) |
| ]) |