| # |
| # When allocating RWX memory, check whether we need to use /dev/zero |
| # as the file descriptor or not. |
| # |
| AC_DEFUN([AC_NEED_DEV_ZERO_FOR_MMAP], |
| [AC_CACHE_CHECK([if /dev/zero is needed for mmap], |
| ac_cv_need_dev_zero_for_mmap, |
| [if test "$llvm_cv_os_type" = "Interix" ; then |
| ac_cv_need_dev_zero_for_mmap=yes |
| else |
| ac_cv_need_dev_zero_for_mmap=no |
| fi |
| ]) |
| if test "$ac_cv_need_dev_zero_for_mmap" = yes; then |
| AC_DEFINE([NEED_DEV_ZERO_FOR_MMAP],[1], |
| [Define if /dev/zero should be used when mapping RWX memory, or undefine if its not necessary]) |
| fi]) |
