strace/m4/long_long.m4
Mike Frysinger 584ba2d31d Fix off_t/rlim_t size checks when cross-compiling
The current off_t/rlim_t size checks (wrt size of long long) use AC_RUN
which obviously doesn't work when cross-compiling.  While we don't hit
any configure errors, the fall back code is pretty dumb (which is to say
there isn't any).  Considering the code in question though, we can use
some fun compiler tricks with sizeof and array lengths to turn it into
a pure build test and avoid the RUN issue completely.

* m4/long_long.m4 (AC_OFF_T_IS_LONG_LONG, AC_RLIM_T_IS_LONG_LONG):
Convert from AC_RUN_IFELSE to AC_COMPILE_IFELSE.

Signed-off-by: Mike Frysinger <vapier@gentoo.org>
2010-09-15 15:36:00 +00:00

62 lines
1.9 KiB
Plaintext

dnl ### A macro to determine if off_t is a long long
AC_DEFUN([AC_OFF_T_IS_LONG_LONG],
[AC_MSG_CHECKING(for long long off_t)
AC_CACHE_VAL(ac_cv_have_long_long_off_t,
[AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <sys/types.h>
char a[(sizeof (off_t) == sizeof (long long) &&
sizeof (off_t) > sizeof (long)) - 1];
]])],[ac_cv_have_long_long_off_t=yes],[ac_cv_have_long_long_off_t=no])])
AC_MSG_RESULT($ac_cv_have_long_long_off_t)
if test "$ac_cv_have_long_long_off_t" = yes
then
AC_DEFINE([HAVE_LONG_LONG_OFF_T], 1, [Define if off_t is a long long.])
fi
])
dnl ### A macro to determine if rlim_t is a long long
AC_DEFUN([AC_RLIM_T_IS_LONG_LONG],
[AC_MSG_CHECKING(for long long rlim_t)
AC_CACHE_VAL(ac_cv_have_long_long_rlim_t,
[AC_COMPILE_IFELSE([AC_LANG_SOURCE([[#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>
char a[(sizeof (rlim_t) == sizeof (long long) &&
sizeof (rlim_t) > sizeof (long)) - 1];
]])],[ac_cv_have_long_long_rlim_t=yes],[ac_cv_have_long_long_rlim_t=no])])
AC_MSG_RESULT($ac_cv_have_long_long_rlim_t)
if test "$ac_cv_have_long_long_rlim_t" = yes
then
AC_DEFINE([HAVE_LONG_LONG_RLIM_T], 1, [Define if rlim_t is a long long.])
fi
])
dnl ### A macro to determine endianness of long long
AC_DEFUN([AC_LITTLE_ENDIAN_LONG_LONG],
[AC_MSG_CHECKING(for little endian long long)
AC_CACHE_VAL(ac_cv_have_little_endian_long_long,
[AC_RUN_IFELSE([AC_LANG_SOURCE([[
int main () {
union {
long long ll;
int l [2];
} u;
u.ll = 0x12345678;
if (u.l[0] == 0x12345678)
return 0;
return 1;
}
]])],[ac_cv_have_little_endian_long_long=yes],[ac_cv_have_little_endian_long_long=no],[
if test "x$ac_cv_c_bigendian" = "xyes"; then
ac_cv_have_little_endian_long_long=no
else
ac_cv_have_little_endian_long_long=yes
fi
])])
AC_MSG_RESULT($ac_cv_have_little_endian_long_long)
if test "$ac_cv_have_little_endian_long_long" = yes
then
AC_DEFINE([HAVE_LITTLE_ENDIAN_LONG_LONG], 1,
[Define if long long is little-endian.])
fi
])