From: "Adam P. Jenkins" <thorin@...>
Date: 2005-05-17T11:35:31+09:00
Subject: Re: Rails on Altix ia64

Nakada, Nobuyoshi wrote:
> Hi,
> 
> At Tue, 17 May 2005 09:55:30 +0900,
> Adam P. Jenkins wrote in [ruby-talk:142863]:
> 
>> Has anyone successfully run a Rails application on an Altix, or other
>> ia64 machine?  I'm getting a segmentation fault in gc.c.  More info 
>> below.
> 
> 
> Some bugs about GC on IA64 have been fixed since 1.8.2 release.  Try
> 1.8.3 preview1.
> 

Thank you for your quick response.  I tried 1.8.3 preview1, and get the 
same error.  When it happens, in gc_mark, ptr is always == 8.  The 
function tries to interpret it as a pointer and dereference it. 
Here's the result of trying my rails app with 1.8.3:

Start webrick:

$ script/server
=> Rails application started on http://0.0.0.0:3000
[2005-05-16 22:37:33] INFO  WEBrick 1.3.1
[2005-05-16 22:37:33] INFO  ruby 1.8.3 (2005-05-12) [ia64-linux]
[2005-05-16 22:37:33] INFO  WEBrick::HTTPServer#start: pid=16740 port=3000


Make a request from my browser, and webrick says:

/home/ajenkins/deploy/lib/ruby/1.8/timeout.rb:41: [BUG] Segmentation fault
ruby 1.8.3 (2005-05-12) [ia64-linux]

Aborted (core dumped)

Stack trace from the core dump shows:

(gdb) bt
#0  raise (sig=0) at ../nptl/sysdeps/unix/sysv/linux/raise.c:30
#1  0x20000000001a4a40 in abort () at ../sysdeps/generic/abort.c:50
#2  0x40000000002051c0 in rb_bug (fmt=0x4000000000228f30 "Segmentation 
fault") at error.c:214
#3  0x400000000017c040 in sigsegv (sig=11) at signal.c:446
#4  <signal handler called>
#5  gc_mark (ptr=Cannot access memory at address 0xfffffffffffffff0
) at gc.c:715
#6  0x400000000007a9d0 in rb_gc_mark (ptr=8) at gc.c:738
#7  0x40000000000519b0 in thread_mark (th=0x6000000000906d40) at eval.c:9793
#8  0x400000000007b6c0 in gc_mark_children (ptr=2305843009236888272, 
lev=2) at gc.c:944
#9  0x400000000007a960 in gc_mark (ptr=2305843009236888272, lev=1) at 
gc.c:731
#10 0x400000000007b960 in gc_mark_children (ptr=2305843009236888352, 
lev=1) at gc.c:976
#11 0x400000000007a960 in gc_mark (ptr=2305843009236888352, lev=0) at 
gc.c:731
#12 0x400000000007a130 in mark_locations_array (x=0x60000ffffff58440, 
n=82490) at gc.c:626
#13 0x400000000007a230 in rb_gc_mark_locations 
(start=0x60000ffffff50760, end=0x60000fffffff9618)
     at gc.c:639
#14 0x400000000007e330 in garbage_collect () at gc.c:1356
#15 0x400000000000f680 in __do_jv_register_classes ()
#16 0x400000000007a730 in gc_mark (ptr=Cannot access memory at address 
0xfffffffffffffff0
) at gc.c:714
#17 0x400000000007a730 in gc_mark (ptr=Cannot access memory at address 
0xfffffffffffffff0
) at gc.c:714
#18 0x0000000000000000 in ?? ()
#19 0x0000000000000000 in ?? ()
Previous frame identical to this frame (corrupt stack?)
(gdb)

Adam