Mercurial > gnulib
view m4/ldexp.m4 @ 17364:7524d97ae56f
stdalign: port to stricter ISO C11
ISO C11 says that _Alignof's operand must be a parenthesized type.
Problem reported by Eli Zaretskii in
<http://lists.gnu.org/archive/html/emacs-devel/2013-03/msg00960.html>.
* doc/posix-headers/stdalign.texi (stdalign.h): Document this.
* m4/stdalign.m4 (gl_STDALIGN_H): Don't use _Alignof (expr).
author | Paul Eggert <eggert@cs.ucla.edu> |
---|---|
date | Fri, 29 Mar 2013 19:47:13 -0700 |
parents | e542fd46ad6f |
children | 344018b6e5d7 |
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# ldexp.m4 serial 1 dnl Copyright (C) 2010-2013 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_LDEXP], [ AC_REQUIRE([gl_CHECK_LDEXP_NO_LIBM]) LDEXP_LIBM= if test $gl_cv_func_ldexp_no_libm = no; then AC_CACHE_CHECK([whether ldexp() can be used with libm], [gl_cv_func_ldexp_in_libm], [ save_LIBS="$LIBS" LIBS="$LIBS -lm" AC_LINK_IFELSE( [AC_LANG_PROGRAM([[#ifndef __NO_MATH_INLINES # define __NO_MATH_INLINES 1 /* for glibc */ #endif #include <math.h> double (*funcptr) (double, int) = ldexp; double x;]], [[return ldexp (x, -1) > 0;]])], [gl_cv_func_ldexp_in_libm=yes], [gl_cv_func_ldexp_in_libm=no]) LIBS="$save_LIBS" ]) if test $gl_cv_func_ldexp_in_libm = yes; then LDEXP_LIBM=-lm fi fi AC_SUBST([LDEXP_LIBM]) ]) dnl Test whether ldexp() can be used without linking with libm. dnl Set gl_cv_func_ldexp_no_libm to 'yes' or 'no' accordingly. AC_DEFUN([gl_CHECK_LDEXP_NO_LIBM], [ AC_CACHE_CHECK([whether ldexp() can be used without linking with libm], [gl_cv_func_ldexp_no_libm], [ AC_LINK_IFELSE( [AC_LANG_PROGRAM([[#ifndef __NO_MATH_INLINES # define __NO_MATH_INLINES 1 /* for glibc */ #endif #include <math.h> double (*funcptr) (double, int) = ldexp; double x;]], [[return ldexp (x, -1) > 0;]])], [gl_cv_func_ldexp_no_libm=yes], [gl_cv_func_ldexp_no_libm=no]) ]) ])