2 dnl Copyright (C) 2011-2012 Free Software Foundation, Inc.
3 dnl This file is free software; the Free Software Foundation
4 dnl gives unlimited permission to copy and/or distribute it,
5 dnl with or without modifications, as long as this notice is preserved.
7 AC_DEFUN([gl_FUNC_LOG10F],
9 AC_REQUIRE([gl_MATH_H_DEFAULTS])
10 AC_REQUIRE([gl_FUNC_LOG10])
12 dnl Persuade glibc <math.h> to declare log10f().
13 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
15 dnl Test whether log10f() exists. Assume that log10f(), if it exists, is
16 dnl defined in the same library as log10().
18 LIBS="$LIBS $LOG10_LIBM"
19 AC_CHECK_FUNCS([log10f])
21 if test $ac_cv_func_log10f = yes; then
22 LOG10F_LIBM="$LOG10_LIBM"
25 LIBS="$LIBS $LOG10F_LIBM"
28 case "$gl_cv_func_log10f_works" in
30 *) REPLACE_LOG10F=1 ;;
35 if test $HAVE_LOG10F = 0 || test $REPLACE_LOG10F = 1; then
36 dnl Find libraries needed to link lib/log10f.c.
37 if test $HAVE_LOG10F = 0; then
38 LOG10F_LIBM="$LOG10_LIBM"
41 AC_SUBST([LOG10F_LIBM])
44 dnl Test whether log10f() works.
45 dnl On OSF/1 5.1, log10f(-0.0f) is NaN.
46 AC_DEFUN([gl_FUNC_LOG10F_WORKS],
48 AC_REQUIRE([AC_PROG_CC])
49 AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
50 AC_CACHE_CHECK([whether log10f works], [gl_cv_func_log10f_works],
66 [gl_cv_func_log10f_works=yes],
67 [gl_cv_func_log10f_works=no],
69 osf*) gl_cv_func_log10f_works="guessing no";;
70 *) gl_cv_func_log10f_works="guessing yes";;