Introduce a test to reproduce bug 123837 (semctl GETVAL false positive)

The test succeeds on amd64, but fails on x86, with the following diff:

+Syscall param semctl(arg) points to uninitialised byte(s)
+   at 0x........: semctl@@GLIBC_2.2 (semctl.c:109)
+   by 0x........: main (sem.c:36)
+ Address 0x........ is on thread 1's stack
+
+Syscall param semctl(arg) points to uninitialised byte(s)
+   at 0x........: semctl@@GLIBC_2.2 (semctl.c:109)
+   by 0x........: main (sem.c:43)
+ Address 0x........ is on thread 1's stack
+



git-svn-id: svn://svn.valgrind.org/valgrind/trunk@13073

memcheck/tests/Makefile.am

@@ -180,6 +180,7 @@ EXTRA_DIST = \
 	realloc2.stderr.exp realloc2.vgtest \
 	realloc3.stderr.exp realloc3.vgtest \
 	sbfragment.stdout.exp sbfragment.stderr.exp sbfragment.vgtest \
+	sem.stderr.exp sem.vgtest \
 	sh-mem.stderr.exp sh-mem.vgtest \
 	sh-mem-random.stderr.exp sh-mem-random.stdout.exp64 \
 	sh-mem-random.stdout.exp sh-mem-random.vgtest \

memcheck/tests/sem.stderr.exp

@@ -0,0 +1,10 @@
+
+
+HEAP SUMMARY:
+    in use at exit: 0 bytes in 0 blocks
+  total heap usage: 0 allocs, 0 frees, 0 bytes allocated
+
+For a detailed leak analysis, rerun with: --leak-check=full
+
+For counts of detected and suppressed errors, rerun with: -v
+ERROR SUMMARY: 0 errors from 0 contexts (suppressed: 0 from 0)

memcheck/tests/sem.vgtest

@@ -0,0 +1 @@
+prog: ../../none/tests/sem

none/tests/sem.c

@@ -7,6 +7,7 @@
 #include <sys/ipc.h>
 #include <sys/sem.h>
 #include <time.h>
+#include <unistd.h>
 int main(int argc, char **argv)
 {
    int semid;
@@ -32,6 +33,20 @@ int main(int argc, char **argv)
       exit(1);
    }
 
+   if (semctl(semid, 0, GETVAL) != 1)
+   {
+      perror("semctl GETVAL");
+      semctl(semid, 0, IPC_RMID);
+      exit(1);
+   }
+
+   if (semctl(semid, 0, GETPID) != getpid())
+   {
+      perror("semctl GETPID");
+      semctl(semid, 0, IPC_RMID);
+      exit(1);
+   }
+
    /* The next call to semtimedop causes the program to hang on
       ppc32-linux (Yellow Dog 4.0).  I don't know why.  Hence the
       extended ifdef. */