1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108
|
# log2l.m4 serial 1
dnl Copyright (C) 2010-2014 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_LOG2L],
[
AC_REQUIRE([gl_MATH_H_DEFAULTS])
AC_REQUIRE([gl_LONG_DOUBLE_VS_DOUBLE])
AC_REQUIRE([gl_FUNC_LOG2])
dnl Persuade glibc <math.h> to declare log2l().
AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])
dnl Test whether log2l() exists. Assume that log2l(), if it exists, is
dnl defined in the same library as log2().
save_LIBS="$LIBS"
LIBS="$LIBS $LOG2_LIBM"
AC_CHECK_FUNCS([log2l])
LIBS="$save_LIBS"
if test $ac_cv_func_log2l = yes; then
LOG2L_LIBM="$LOG2_LIBM"
HAVE_LOG2L=1
dnl Also check whether it's declared.
dnl IRIX 6.5 has log2l() in libm but doesn't declare it in <math.h>.
AC_CHECK_DECL([log2l], , [HAVE_DECL_LOG2L=0], [[#include <math.h>]])
save_LIBS="$LIBS"
LIBS="$LIBS $LOG2L_LIBM"
gl_FUNC_LOG2L_WORKS
LIBS="$save_LIBS"
case "$gl_cv_func_log2l_works" in
*yes) ;;
*) REPLACE_LOG2L=1 ;;
esac
else
HAVE_LOG2L=0
HAVE_DECL_LOG2L=0
fi
if test $HAVE_LOG2L = 0 || test $REPLACE_LOG2L = 1; then
dnl Find libraries needed to link lib/log2l.c.
if test $HAVE_SAME_LONG_DOUBLE_AS_DOUBLE = 1; then
LOG2L_LIBM="$LOG2_LIBM"
else
AC_REQUIRE([gl_FUNC_ISNANL])
AC_REQUIRE([gl_FUNC_FREXPL])
AC_REQUIRE([gl_FUNC_LOGL])
LOG2L_LIBM=
dnl Append $ISNANL_LIBM to LOG2L_LIBM, avoiding gratuitous duplicates.
case " $LOG2L_LIBM " in
*" $ISNANL_LIBM "*) ;;
*) LOG2L_LIBM="$LOG2L_LIBM $ISNANL_LIBM" ;;
esac
dnl Append $FREXPL_LIBM to LOG2L_LIBM, avoiding gratuitous duplicates.
case " $LOG2L_LIBM " in
*" $FREXPL_LIBM "*) ;;
*) LOG2L_LIBM="$LOG2L_LIBM $FREXPL_LIBM" ;;
esac
dnl Append $LOGL_LIBM to LOG2L_LIBM, avoiding gratuitous duplicates.
case " $LOG2L_LIBM " in
*" $LOGL_LIBM "*) ;;
*) LOG2L_LIBM="$LOG2L_LIBM $LOGL_LIBM" ;;
esac
fi
fi
AC_SUBST([LOG2L_LIBM])
])
dnl Test whether log2l() works.
dnl On OSF/1 5.1, log2l(-0.0) is NaN.
AC_DEFUN([gl_FUNC_LOG2L_WORKS],
[
AC_REQUIRE([AC_PROG_CC])
AC_REQUIRE([AC_CANONICAL_HOST]) dnl for cross-compiles
AC_CACHE_CHECK([whether log2l works], [gl_cv_func_log2l_works],
[
AC_RUN_IFELSE(
[AC_LANG_SOURCE([[
#include <math.h>
#ifndef log2l /* for AIX */
extern
#ifdef __cplusplus
"C"
#endif
long double log2l (long double);
#endif
volatile long double x;
volatile long double y;
int main ()
{
/* This test fails on OSF/1 5.1. */
x = -0.0L;
y = log2l (x);
if (!(y + y == y))
return 1;
return 0;
}
]])],
[gl_cv_func_log2l_works=yes],
[gl_cv_func_log2l_works=no],
[case "$host_os" in
osf*) gl_cv_func_log2l_works="guessing no";;
*) gl_cv_func_log2l_works="guessing yes";;
esac
])
])
])
|