Bug in Lua 5.0.2

[Spencer Schumann <gauchopuro@...>]

I've been experiencing some random crashes within the Lua interpreter
in code that makes heavy use of coroutines.  I've distilled the
offending code down to the following:

-----------------------------------------------------------------
local thread_id = 0
local threads = {}

function fn(thread)
    thread_id = thread_id + 1
    threads[thread_id] = function()
			     thread = nil
			 end
    coroutine.yield()
end

while true do
    local thread = coroutine.create(fn)
    coroutine.resume(thread, thread)
end
-----------------------------------------------------------------

I've run this code under Windows, using builds from several compilers,
and also under Solaris; the code produces a segfault in under a
second.

Enabling lua assertions shows several failed assertions.  The exact
assertions are sensitive to small changes in the above code; however,
one consistent assertion failure happens at lgc.c, line 222.

I plan on digging into this problem further, but I thought I'd post
the crash-producing code now in case anyone else wants to dig into it.