dnl @synopsis AX_FUNC_POSIX_MEMALIGN
dnl
dnl Some versions of posix_memalign (notably glibc 2.2.5) incorrectly
dnl apply their power-of-two check to the size argument, not the alignment
dnl argument. AX_FUNC_POSIX_MEMALIGN defines HAVE_POSIX_MEMALIGN if the
dnl power-of-two check is correctly applied to the alignment argument.
dnl
dnl @version $Id: $
dnl @author Scott Pakin <pakin@uiuc.edu>
dnl
AC_DEFUN([AX_FUNC_POSIX_MEMALIGN],
[AC_CACHE_CHECK([for working posix_memalign],
[ax_cv_func_posix_memalign_works],
[AC_TRY_RUN([
#include <stdlib.h>
int
main ()
{
void *buffer;
/* Some versions of glibc incorrectly perform the alignment check on
* the size word. */
exit (posix_memalign (&buffer, sizeof(void *), 123) != 0);
}
],
[ax_cv_func_posix_memalign_works=yes],
[ax_cv_func_posix_memalign_works=no],
[ax_cv_func_posix_memalign_works=no])])
if test "$ax_cv_func_posix_memalign_works" = "yes" ; then
AC_DEFINE([HAVE_POSIX_MEMALIGN], [1],
[Define to 1 if `posix_memalign' works.])
fi
])