[racket-dev] calling make-keyword-procedure from inside a thread produces a stack overflow in scheme_uncopy_stack

From: Matthew Flatt (mflatt at cs.utah.edu)
Date: Wed May 15 08:47:43 EDT 2013

I didn't get from your earlier message that provoking the crash is as
easy as running the expression below, but I am indeed able to replicate
the problem immediately.

Also, I have been swamped for the last couple of weeks, but I should be
able to get to this soon.

Thanks!

At Wed, 15 May 2013 13:40:04 +0100, Matthew Eric Bassett wrote:
> This is related to 
> http://www.mail-archive.com/users@racket-lang.org/msg17597.html. Forgive 
> me for posting it again, I wanted to make sure it didn't disappear into 
> a black hole.
> 
> Launching a racket thread that calls make-keyword-procedure may produce 
> a seg fault.  For instance,
> 
> (let loop () (thread (make-keyword-procedure (lambda (x y) '()))) 
> (loop))
> 
> Reliably causes a seg fault.  Repeatedly calling
> 
> (thread (make-keyword-procedure (lambda (x y) '())))
> 
> will eventually (but not consistently) produce a seg fault.  Functions 
> defined with make-keyword-procedure, such as const and thunk* suffer the 
> same fate (plain ol' thunk is fine).
> 
> A coredump of the racket repl from this segfault shows a stack overflow 
> in scheme_uncopy_stack, with the Scheme_Jumpup_Buf zeroed out.  Please 
> see our gdp session at http://pastebin.com/aBx2FTcK (This is from racket 
> compiled without optimization)  or cause your own seg fault with the 
> above code.
> 
> Perhaps we're being incredibly daft to write code where we'd need to 
> const or thunk* something inside a thread, or perhaps this is a bug in 
> racket.  We might just be incredibly daft by calling a const inside a 
> thread, or this is a bug in racket, or something else is up.  In any 
> case, we've exhausted our abilities to investigate it further and would 
> appreciate advice from those more familiar with the code.
> 
> Regards,
> 
> --
> Matthew Eric Bassett | http://mebassett.info
> _________________________
>   Racket Developers list:
>   http://lists.racket-lang.org/dev

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