Patch from Ralf Corsepius <corsepiu@faw.uni-ulm.de>:

    After upgrading my linux box to the brand new SuSE 6.2 release, which is
    glibc-2.1 based, I came across a bug in RTEMS - IIRC, I even warned you
    about it about 1/2 a year ago, but nothing has been done since then :-.

    The *.m4 macros to check for SYSV/IPC are broken for linux/glibc2.1,
    because they assume that linux always defines union semun, which isn't
    true anymore for glibc2.1 (the manpage for semctl states _X_OPEN
    specifies it this way). Therefore I have tried to implement a more
    general approach for handling SYSV for unix/posix which checks for
    presence of struct semun, instead of trying  to evaluate OS specific
    preprocessor symbols.

    This approach is a bit adventureous, because I only tested it with
    linux/glibc2.1 and linux/libc5, but not under other Unix variants RTEMS
    supports. I am quite confident it will work on other hosts, too, but who
    knows :-.

    [FYI: I think this might also is the cause of some problems with RedHat
    6.X / Mandrake linux recently reported on the rtems list -- rtems-4.0.0
    can not be build for posix on any glibc2.1 based host]

    Furthermore the patch below contains a couple of minor fixes and
    configuration cleanups, which IMO should be applied before releasing a
    new snapshot.

    To apply this patch:

        cd <source-tree>
        patch -p1 < rtems-rc-19990709-8.diff
        ./autogen

1 files changed, 0 insertions, 115 deletions

diff --git a/c/src/lib/aclocal.m4 b/c/src/lib/aclocal.m4
index 2fbb5bdf3c..51eae57574 100644
--- a/c/src/lib/aclocal.m4
+++ b/c/src/lib/aclocal.m4
@@ -732,121 +732,6 @@ EOF
 ])
 
 
-dnl
-dnl $Id$
-dnl
-dnl Check for System V IPC calls used by Unix simulators
-dnl
-dnl 98/07/17 Dario Alcocer     alcocer@netcom.com
-dnl 	     Ralf Corsepius    corsepiu@faw.uni-ulm.de
-dnl
-dnl Note: $host_os should probably *not* ever be used here to
-dnl determine if host supports System V IPC calls, since some
-dnl (e.g. FreeBSD 2.x) are configured by default to include only
-dnl a subset of the System V IPC calls.  Therefore, to make sure
-dnl all of the required calls are found, test for each call explicitly.
-dnl
-dnl All of the calls use IPC_PRIVATE, so tests will not unintentionally
-dnl modify any existing key sets.  See the man pages for semget, shmget, 
-dnl msgget, semctl, shmctl and msgctl for details.
-
-AC_DEFUN(RTEMS_SYSV_SEM,
-[AC_REQUIRE([AC_PROG_CC]) 
-AC_REQUIRE([RTEMS_CANONICAL_HOST])
-AC_CACHE_CHECK(whether $RTEMS_HOST supports System V semaphores,
-rtems_cv_sysv_sem,
-[
-AC_TRY_RUN([
-#include <sys/types.h>
-#include <sys/ipc.h>
-#include <sys/sem.h>
-int main () {
-#if !defined(sun) 
-  union semun arg ;
-#else
-  union semun {
-    int val;
-    struct semid_ds *buf;
-    ushort *array;
-  } arg;
-#endif
-  int id=semget(IPC_PRIVATE,1,IPC_CREAT|0400);
-  if (id == -1)
-    exit(1);
-  arg.val = 0; /* avoid implicit type cast to union */
-  if (semctl(id, 0, IPC_RMID, arg) == -1)
-    exit(1);
-  exit(0);
-}
-],
-rtems_cv_sysv_sem="yes", rtems_cv_sysv_sem="no", :)
-])
-])
-
-AC_DEFUN(RTEMS_SYSV_SHM,
-[AC_REQUIRE([AC_PROG_CC]) 
-AC_REQUIRE([RTEMS_CANONICAL_HOST])
-AC_CACHE_CHECK(whether $RTEMS_HOST supports System V shared memory,
-rtems_cv_sysv_shm,
-[
-AC_TRY_RUN([
-#include <sys/types.h>
-#include <sys/ipc.h>
-#include <sys/shm.h>
-int main () {
-  int id=shmget(IPC_PRIVATE,1,IPC_CREAT|0400);
-  if (id == -1)
-    exit(1);
-  if (shmctl(id, IPC_RMID, 0) == -1)
-    exit(1);
-  exit(0);
-}
-],
-rtems_cv_sysv_shm="yes", rtems_cv_sysv_shm="no", :)
-])
-])
-
-AC_DEFUN(RTEMS_SYSV_MSG,
-[AC_REQUIRE([AC_PROG_CC]) 
-AC_REQUIRE([RTEMS_CANONICAL_HOST])
-AC_CACHE_CHECK(whether $RTEMS_HOST supports System V messages,
-rtems_cv_sysv_msg,
-[
-AC_TRY_RUN([
-#include <sys/types.h>
-#include <sys/ipc.h>
-#include <sys/msg.h>
-int main () {
-  int id=msgget(IPC_PRIVATE,IPC_CREAT|0400);
-  if (id == -1)
-    exit(1);
-  if (msgctl(id, IPC_RMID, 0) == -1)
-    exit(1);
-  exit(0);
-}
-],
-rtems_cv_sysv_msg="yes", rtems_cv_sysv_msg="no", :)
-])
-])
-
-AC_DEFUN(RTEMS_CHECK_SYSV_UNIX,
-[AC_REQUIRE([RTEMS_CANONICAL_HOST])
-if test "$RTEMS_CPU" = "unix" ; then
-  RTEMS_SYSV_SEM
-  if test "$rtems_cv_sysv_sem" != "yes" ; then
-    AC_MSG_ERROR([System V semaphores don't work, required by simulator])
-  fi
-  RTEMS_SYSV_SHM
-  if test "$rtems_cv_sysv_shm" != "yes" ; then
-    AC_MSG_ERROR([System V shared memory doesn't work, required by simulator])
-  fi
-  RTEMS_SYSV_MSG
-  if test "$rtems_cv_sysv_msg" != "yes" ; then
-    AC_MSG_ERROR([System V messages don't work, required by simulator])
-  fi
-fi
-])
-
 dnl $Id$
 
 dnl Report all available bsps for a target,