Thank you Junio

On Thu, 10 Aug 2017, Junio C Hamano wrote:
> There is only one getdelim() call, which was introduced in v2.5.0
> timeframe, and it is used like this:

>       r = getdelim(&sb->buf, &sb->alloc, term, fp);

>       if (r > 0) {
>               sb->len = r;
>               return 0;
>       }
>       assert(r == -1);

>       /*
>        * Normally we would have called xrealloc, which will try to free
>        * memory and recover. But we have no way to tell getdelim() to do so.
>        * Worse, we cannot try to recover ENOMEM ourselves, because we have
>        * no idea how many bytes were read by getdelim.
>        *
>        * Dying here is reasonable. It mirrors what xrealloc would do on
>        * catastrophic memory failure. We skip the opportunity to free pack
>        * memory and retry, but that's unlikely to help for a malloc small
>        * enough to hold a single line of input, anyway.
>        */
>       if (errno == ENOMEM)
>               die("Out of memory, getdelim failed");

> So the function is returning -1 and leaving ENOMEM in errno on
> Yaroslav's system.  

> I wonder if we are truly hitting out of memory, though.  The same
> symptom could bee seen if getdelim() does not touch errno when it
> returns -1, but some other system call earlier set it to ENOMEM,
> for example.

> If the same version of Git is recompiled there without HAVE_GETDELIM
> defined, would it still die with out of memory (presumably inside
> the call to strbuf_grow() in the strbuf_getwholeline() function)?

will check now...  for my own education (rotten by Python) -- how
do you know which syscall set errno to be analyzed at this specific
point?  may be it was already set to ENOMEM before entry to this
function?

-- 
Yaroslav O. Halchenko
Center for Open Neuroscience     http://centerforopenneuroscience.org
Dartmouth College, 419 Moore Hall, Hinman Box 6207, Hanover, NH 03755
Phone: +1 (603) 646-9834                       Fax: +1 (603) 646-1419
WWW:   http://www.linkedin.com/in/yarik        

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