path: root/aclocal
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authorJoel Sherrill <>1999-08-12 18:22:17 +0000
committerJoel Sherrill <>1999-08-12 18:22:17 +0000
commitea562ee977d4b48500a9b117e543e9c4ae0eb05e (patch)
treeeece22c6292c13b788f7baafc4da8471283c0ff2 /aclocal
parentPatch from Tony R. Ambardar <>: (diff)
Patch from Ralf Corsepius <>:
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
Diffstat (limited to 'aclocal')
1 files changed, 25 insertions, 6 deletions
diff --git a/aclocal/sysv-ipc.m4 b/aclocal/sysv-ipc.m4
index 59a5f5b50c..883921e2c8 100644
--- a/aclocal/sysv-ipc.m4
+++ b/aclocal/sysv-ipc.m4
@@ -16,26 +16,44 @@ 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_CACHE_CHECK([whether $RTEMS_HOST defines union semun],
+ rtems_cv_HAS_UNION_SEMUN,
+#include <sys/types.h>
+#include <sys/ipc.h>
+#include <sys/sem.h>],
+[union semun arg ;],
+if test "$rtems_cv_HAS_UNION_SEMUN" = "yes"; then
AC_CACHE_CHECK(whether $RTEMS_HOST supports System V semaphores,
#include <sys/types.h>
#include <sys/ipc.h>
#include <sys/sem.h>
-int main () {
-#if !defined(sun)
- union semun arg ;
union semun {
int val;
struct semid_ds *buf;
ushort *array;
- } arg;
+ } ;
+int main () {
+ union semun arg ;
int id=semget(IPC_PRIVATE,1,IPC_CREAT|0400);
if (id == -1)
@@ -98,6 +116,7 @@ rtems_cv_sysv_msg="yes", rtems_cv_sysv_msg="no", :)
if test "$RTEMS_CPU" = "unix" ; then
if test "$rtems_cv_sysv_sem" != "yes" ; then
AC_MSG_ERROR([System V semaphores don't work, required by simulator])