diff options
author | Andreas Rottmann <a.rottmann@gmx.at> | 2009-09-14 12:32:44 +0200 |
---|---|---|
committer | Andreas Rottmann <a.rottmann@gmx.at> | 2009-09-14 12:32:44 +0200 |
commit | fa095a4504cbe668e4244547e2c141597bea4ecf (patch) | |
tree | 06135820a286ffec47804e75fbf8a147e92acd2e /gnulib-m4/ldexpl.m4 |
Imported Upstream version 0.9.1upstream/0.9.1
Diffstat (limited to 'gnulib-m4/ldexpl.m4')
-rw-r--r-- | gnulib-m4/ldexpl.m4 | 88 |
1 files changed, 88 insertions, 0 deletions
diff --git a/gnulib-m4/ldexpl.m4 b/gnulib-m4/ldexpl.m4 new file mode 100644 index 00000000..8ba85c61 --- /dev/null +++ b/gnulib-m4/ldexpl.m4 @@ -0,0 +1,88 @@ +# ldexpl.m4 serial 4 +dnl Copyright (C) 2007-2009 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_LDEXPL], +[ + AC_REQUIRE([gl_MATH_H_DEFAULTS]) + LDEXPL_LIBM= + AC_CACHE_CHECK([whether ldexpl() can be used without linking with libm], + [gl_cv_func_ldexpl_no_libm], + [ + AC_TRY_LINK([#include <math.h> + long double x;], + [return ldexpl (x, -1) > 0;], + [gl_cv_func_ldexpl_no_libm=yes], + [gl_cv_func_ldexpl_no_libm=no]) + ]) + if test $gl_cv_func_ldexpl_no_libm = no; then + AC_CACHE_CHECK([whether ldexpl() can be used with libm], + [gl_cv_func_ldexpl_in_libm], + [ + save_LIBS="$LIBS" + LIBS="$LIBS -lm" + AC_TRY_LINK([#include <math.h> + long double x;], + [return ldexpl (x, -1) > 0;], + [gl_cv_func_ldexpl_in_libm=yes], + [gl_cv_func_ldexpl_in_libm=no]) + LIBS="$save_LIBS" + ]) + if test $gl_cv_func_ldexpl_in_libm = yes; then + LDEXPL_LIBM=-lm + fi + fi + if test $gl_cv_func_ldexpl_no_libm = yes \ + || test $gl_cv_func_ldexpl_in_libm = yes; then + save_LIBS="$LIBS" + LIBS="$LIBS $LDEXPL_LIBM" + gl_FUNC_LDEXPL_WORKS + LIBS="$save_LIBS" + case "$gl_cv_func_ldexpl_works" in + *yes) gl_func_ldexpl=yes ;; + *) gl_func_ldexpl=no; REPLACE_LDEXPL=1; LDEXPL_LIBM= ;; + esac + else + gl_func_ldexpl=no + fi + if test $gl_func_ldexpl = yes; then + AC_DEFINE([HAVE_LDEXPL], [1], + [Define if the ldexpl() function is available.]) + dnl Also check whether it's declared. + dnl MacOS X 10.3 has ldexpl() in libc but doesn't declare it in <math.h>. + AC_CHECK_DECL([ldexpl], , [HAVE_DECL_LDEXPL=0], [#include <math.h>]) + else + HAVE_DECL_LDEXPL=0 + AC_LIBOBJ([ldexpl]) + fi + AC_SUBST([LDEXPL_LIBM]) +]) + +dnl Test whether ldexpl() works on finite numbers (this fails on AIX 5.1 +dnl and MacOS X 10.4/PowerPC). +AC_DEFUN([gl_FUNC_LDEXPL_WORKS], +[ + AC_REQUIRE([AC_PROG_CC]) + AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles + AC_CACHE_CHECK([whether ldexpl works], [gl_cv_func_ldexpl_works], + [ + AC_TRY_RUN([ +#include <math.h> +extern long double ldexpl (long double, int); +int main() +{ + volatile long double x1 = 1.0; + volatile long double y1 = ldexpl (x1, -1); + volatile long double x2 = 1.73205L; + volatile long double y2 = ldexpl (x2, 0); + return (y1 != 0.5L) || (y2 != x2); +}], [gl_cv_func_ldexpl_works=yes], [gl_cv_func_ldexpl_works=no], + [case "$host_os" in + aix*) gl_cv_func_ldexpl_works="guessing no";; + *) gl_cv_func_ldexpl_works="guessing yes";; + esac + ]) + ]) +]) |