Thread/GC failure of gcj-3.3.1 on netbsd-current

[Bart Locanthi <bart at sabl dot com>]

This isn't quite a cross-post, and I suspect the problem described here 
has more to do with NetBSD than GCJ, but I'm hoping the symptom rings 
some bells here that would lead to understanding in NetBSD-land.

netbsd-current has kernel threads, and gcc-3.3.1 installs fine via 
pkgsrc on it. Simple threaded things work (which they didn't up through 
NetBSD-1.6.1) .. until they require a GC. Then all hell breaks loose, in 
a way very similar to that observed in this two-year-old post.

http://gcc.gnu.org/ml/java/2001-12/msg00141.html

I'm wondering if there's something fundamental with kernel threads on 
netbsd-current, or if there's some odd environmental thing (though see 
below for PATH and LD_LIBRARY_PATH settings), or perhaps a configuration 
thing done wrong by the pkgsrc.

After updating to *really* current (20030917 == 1.6ZC) and 
deinstalling/distclean/installing gcc-3.3.1, I am still unable to get 
very far with Threads under GCJ/NetBSD. This and vastly more complex 
examples work fine under Linux.

Program, execution, and stack trace below:

$ cat al.java
public class al extends Thread {
      int n;
      int m;
      public al(int i, int j) {
              n = i;
              m = j;
      }
      public void run() {
              for (int i = 0; i < n; i++)
                      System.err.println("hello world: "+m+": "+i);
      }
      static public void main(String arg[]) {
              int N = 10000;
              int M = 10;
              if (arg.length > 0)
                      N = Integer.parseInt(arg[0]);
              if (arg.length > 1)
                      M = Integer.parseInt(arg[1]);
              for (int j = 0; j < M; j++)
                      new al(N, j).start();
      }
}
$ echo $PATH
/usr/pkg/gcc3/bin:/usr/pkg/bin:/usr/local/bin:/usr/bin:/bin
$ echo $LD_LIBRARY_PATH
/usr/pkg/gcc3/lib:/usr/pkg/lib
$ gcj -o al -g --main=al al.java
$ ./al 100 10 # 10 threads counting to 100
hello world: 0: 0
hello world: 0: 1
hello world: 0: 2
...
hello world: 6: 47
hello world: 6: 48
Segmentation fault (core dumped)
$ gdb al al.core
GNU gdb 5.3
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GDB is free software, covered by the GNU General Public License, and you 
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welcome to change it and/or distribute copies of it under certain 
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Type "show copying" to see the conditions.
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This GDB was configured as "i386--netbsdelf"...
Core was generated by `al'.
Program terminated with signal 11, Segmentation fault.
Reading symbols from /usr/libexec/ld.elf_so...done.
Loaded symbols for /usr/libexec/ld.elf_so
Reading symbols from /usr/pkg/gcc3/lib/libgcc_s.so.1...done.
Loaded symbols for /usr/pkg/gcc3/lib/libgcc_s.so.1
Reading symbols from /usr/pkg/gcc3/lib/libgcj.so.4...done.
Loaded symbols for /usr/pkg/gcc3/lib/libgcj.so.4
Reading symbols from /usr/lib/libm387.so.0...done.
Loaded symbols for /usr/lib/libm387.so.0
Reading symbols from /usr/lib/libm.so.0...done.
Loaded symbols for /usr/lib/libm.so.0
Reading symbols from /usr/lib/libpthread.so.0...done.
Loaded symbols for /usr/lib/libpthread.so.0
Reading symbols from /usr/lib/libz.so.0...done.
Loaded symbols for /usr/lib/libz.so.0
Reading symbols from /usr/lib/libc.so.12...done.
Loaded symbols for /usr/lib/libc.so.12
Reading symbols from /usr/lib/i18n/libiconv_std.so.4.3...done.
Loaded symbols for /usr/lib/i18n/libiconv_std.so.4.3
Reading symbols from /usr/lib/i18n/libUTF8.so.4.3...done.
Loaded symbols for /usr/lib/i18n/libUTF8.so.4.3
Reading symbols from /usr/lib/i18n/libUTF1632.so.4.3...done.
Loaded symbols for /usr/lib/i18n/libUTF1632.so.4.3
Reading symbols from /usr/lib/i18n/libmapper_none.so.4.3...done.
Loaded symbols for /usr/lib/i18n/libmapper_none.so.4.3
#0  0x48563737 in GC_clear_stack_inner () from 
/usr/pkg/gcc3/lib/libgcj.so.4
(gdb) bt
#0  0x48563737 in GC_clear_stack_inner () from 
/usr/pkg/gcc3/lib/libgcj.so.4
#1  0x48563788 in GC_clear_stack_inner () from 
/usr/pkg/gcc3/lib/libgcj.so.4
#2  0x48563788 in GC_clear_stack_inner () from 
/usr/pkg/gcc3/lib/libgcj.so.4
...
#282 0x48563788 in GC_clear_stack_inner () from 
/usr/pkg/gcc3/lib/libgcj.so.4
#283 0x48563788 in GC_clear_stack_inner () from 
/usr/pkg/gcc3/lib/libgcj.so.4
#284 0x48563885 in GC_clear_stack () from /usr/pkg/gcc3/lib/libgcj.so.4
#285 0x48560a72 in GC_malloc_atomic () from /usr/pkg/gcc3/lib/libgcj.so.4
#286 0x48379d0b in _Jv_NewPrimArray () from /usr/pkg/gcc3/lib/libgcj.so.4
#287 0x4841f425 in 
gnu.gcj.runtime.StringBuffer.StringBuffer(java.lang.String)
  (this=0x80e1630, str=0x80779f0) at gnu/gcj/runtime/StringBuffer.java:179
#288 0x0804923e in al.run() (this=0x80adea0) at al.java:10
#289 0x483b368e in _Jv_ThreadRun(java::lang::Thread*) ()
 from /usr/pkg/gcc3/lib/libgcj.so.4
#290 0x4855b170 in really_start(void*) () from 
/usr/pkg/gcc3/lib/libgcj.so.4
#291 0x4895399e in pthread_create () from /usr/lib/libpthread.so.0