>> Robert  McGovern wrote in [ruby-talk:106071]:
>> Initial backtrace yields nothing useful:
>
> You'll need also -g3 -ggdb options.

Hmm that didn't help, I assume that I am doing something wrong.

If CFLAGS=-g3 -ggdb are used, then the problem does not occur (with 0 to 25 arguments)

Which CFLAGS=-g3 -O2 -ggdb 

$ gdb ruby
<snip gdb preamble>
(gdb) run opttest.rb 1 2 3 4
Starting program: /usr/local/bin/ruby.exe opttest.rb 1 2 3 4
#<Object:0x1010b9e8 @exec=true>
ARGV = 1 2 3 4

Program exited normally.
(gdb) run opttest.rb 1 2 3 4 5  
Starting program: /usr/local/bin/ruby.exe opttest.rb 1 2 3 4 5

Program received signal SIGSEGV, Segmentation fault.
0x00000000 in ?? () from 
(gdb) bt
#0  0x00000000 in ?? () from 
(gdb) quit

Rob