HCoop / bpt / guile.git / blame
| Commit | Line | Data |
|---|---|---|
| dd36ce77 | 1 | # ldexp.m4 serial 1 |
| af07e104 | 2 | dnl Copyright (C) 2010-2013 Free Software Foundation, Inc. |
| dd36ce77 MW |
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. | |
| 6 | ||
| 7 | AC_DEFUN([gl_FUNC_LDEXP], | |
| 8 | [ | |
| 9 | AC_REQUIRE([gl_CHECK_LDEXP_NO_LIBM]) | |
| 10 | LDEXP_LIBM= | |
| 11 | if test $gl_cv_func_ldexp_no_libm = no; then | |
| 12 | AC_CACHE_CHECK([whether ldexp() can be used with libm], | |
| 13 | [gl_cv_func_ldexp_in_libm], | |
| 14 | [ | |
| 15 | save_LIBS="$LIBS" | |
| 16 | LIBS="$LIBS -lm" | |
| 17 | AC_LINK_IFELSE( | |
| 18 | [AC_LANG_PROGRAM([[#ifndef __NO_MATH_INLINES | |
| 19 | # define __NO_MATH_INLINES 1 /* for glibc */ | |
| 20 | #endif | |
| 21 | #include <math.h> | |
| 22 | double (*funcptr) (double, int) = ldexp; | |
| 23 | double x;]], | |
| 24 | [[return ldexp (x, -1) > 0;]])], | |
| 25 | [gl_cv_func_ldexp_in_libm=yes], | |
| 26 | [gl_cv_func_ldexp_in_libm=no]) | |
| 27 | LIBS="$save_LIBS" | |
| 28 | ]) | |
| 29 | if test $gl_cv_func_ldexp_in_libm = yes; then | |
| 30 | LDEXP_LIBM=-lm | |
| 31 | fi | |
| 32 | fi | |
| 33 | AC_SUBST([LDEXP_LIBM]) | |
| 34 | ]) | |
| 35 | ||
| 36 | dnl Test whether ldexp() can be used without linking with libm. | |
| 37 | dnl Set gl_cv_func_ldexp_no_libm to 'yes' or 'no' accordingly. | |
| 38 | AC_DEFUN([gl_CHECK_LDEXP_NO_LIBM], | |
| 39 | [ | |
| 40 | AC_CACHE_CHECK([whether ldexp() can be used without linking with libm], | |
| 41 | [gl_cv_func_ldexp_no_libm], | |
| 42 | [ | |
| 43 | AC_LINK_IFELSE( | |
| 44 | [AC_LANG_PROGRAM([[#ifndef __NO_MATH_INLINES | |
| 45 | # define __NO_MATH_INLINES 1 /* for glibc */ | |
| 46 | #endif | |
| 47 | #include <math.h> | |
| 48 | double (*funcptr) (double, int) = ldexp; | |
| 49 | double x;]], | |
| 50 | [[return ldexp (x, -1) > 0;]])], | |
| 51 | [gl_cv_func_ldexp_no_libm=yes], | |
| 52 | [gl_cv_func_ldexp_no_libm=no]) | |
| 53 | ]) | |
| 54 | ]) |