2 dnl Copyright (C) 2007 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_ISFINITE],
9 AC_REQUIRE([gl_MATH_H_DEFAULTS])
10 dnl Persuade glibc <math.h> to declare isfinite.
11 AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
12 AC_CHECK_DECLS([isfinite], , , [#include <math.h>])
13 if test "$ac_cv_have_decl_isfinite" = yes; then
14 gl_CHECK_MATH_LIB([ISFINITE_LIBM], [x = isfinite (x);])
16 if test "$ac_cv_have_decl_isfinite" != yes ||
17 test "$ISFINITE_LIBM" = missing; then
22 AC_SUBST([HAVE_DECL_ISFINITE])
23 AC_SUBST([ISFINITE_LIBM])