| # exp2f.m4 serial 1 |
| 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_EXP2F], |
| [ |
| AC_REQUIRE([gl_MATH_H_DEFAULTS]) |
| AC_REQUIRE([gl_FUNC_EXP2]) |
| |
| dnl Persuade glibc <math.h> to declare exp2f(). |
| AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS]) |
| |
| dnl Test whether exp2f() exists. Assume that exp2f(), if it exists, is |
| dnl defined in the same library as exp2(). |
| save_LIBS="$LIBS" |
| LIBS="$LIBS $EXP2_LIBM" |
| AC_CHECK_FUNCS([exp2f]) |
| LIBS="$save_LIBS" |
| if test $ac_cv_func_exp2f = yes; then |
| HAVE_EXP2F=1 |
| EXP2F_LIBM="$EXP2_LIBM" |
| dnl Also check whether it's declared. |
| dnl IRIX 6.5 has exp2f() in libm but doesn't declare it in <math.h>. |
| AC_CHECK_DECL([exp2f], , [HAVE_DECL_EXP2F=0], [[#include <math.h>]]) |
| else |
| HAVE_EXP2F=0 |
| HAVE_DECL_EXP2F=0 |
| dnl Find libraries needed to link lib/exp2f.c. |
| EXP2F_LIBM="$EXP2_LIBM" |
| fi |
| AC_SUBST([EXP2F_LIBM]) |
| ]) |
