[Bug libgcj/49451] New: FileHandleGcTest FAILS on IRIX

["ro at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=49451

           Summary: FileHandleGcTest FAILS on IRIX
           Product: gcc
           Version: 4.7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: libgcj
        AssignedTo: unassigned@gcc.gnu.org
        ReportedBy: ro@gcc.gnu.org
                CC: tromey@gcc.gnu.org, aph@gcc.gnu.org, Hans.Boehm@hp.com
              Host: mips-sgi-irix6.5
            Target: mips-sgi-irix6.5
             Build: mips-sgi-irix6.5


The FileHandleGcTest FAILS on IRIX 6.5 (both N32 and N64 ABIs):

FAIL: FileHandleGcTest execution - source compiled test
FAIL: FileHandleGcTest -findirect-dispatch execution - source compiled test
FAIL: FileHandleGcTest -O3 execution - source compiled test
FAIL: FileHandleGcTest -O3 -findirect-dispatch execution - source compiled test

In the log, I find:

/proc open failed

This message is ultimately from boehm-gc/dyn_load.c
(GC_register_dynamic_libraries) or boehm-gc/os_dep.c (GC_dirty_init).  I had to
add a discriminator to the message to find it's the former.  Running the test
under par, I find

 1061mS[  3]FileHandleGcTest(69051502): open("/dev/null", O_RDONLY, 0666) =
1023
 1062mS[  3]FileHandleGcTest(69051502): open("/dev/null", O_RDONLY, 0666) errno 
= 24 (Too many open files)
 1063mS[  3]FileHandleGcTest(69051502): open("/proc/69051502", O_RDONLY, 0)
errn
o = 24 (Too many open files)
 1063mS[  3]FileHandleGcTest(69051502): write(2, "/proc open failed\n", 18) =
18
open             1056      0.07     72.78

When in gnu/java/nio/channels/natFileChannelPosix.cc (FileChannelImpl::open) an
open call fails, the code runs

      ::java::lang::System::gc ();
      ::java::lang::System::runFinalization ();

to try and free fds.  Unfortunately, in boehm-gc
(GC_register_dynamic_libraries)
an attempt is made to open /proc/<pid>, which of course fails and calls
abort().

This doesn't happen on either Solaris or Tru64 UNIX because those use their
own implementations of GC_register_dynamic_libraries which don't need
additional file descriptors.

I guess something similar can be implemented on IRIX, using __rld_obj_head 
described in rld(5).  I''ll probably give it a try.