Re: BUG #14582: ecpg crashes on SQL input

> After some googling, the answer seems to be that glibc's detection of
> double free() is really unreliable for small chunks.  It will
> basically
> only notice an extra free of the same chunk most recently freed
> within a
> given bin (size range).  Since in the problem at hand there are
> probably
> unrelated free's happening between the two free's mentioning the same
> chunk, it's quite easy for it to miss the error.  I'm still a bit
> unsure
> why I see the crash in 9.6 but not HEAD, because there's very little
> difference between them, but I no longer feel that we need to
> investigate
> more closely.

On my system I don't see this segfault at all, unless I run it under
valgrind.

> This all suggests that it might be worth testing ecpg with a
> debugging
> malloc library that has more robust error detection ...

I sometimes do. However, the library is more important imo, a leak in a
short running application like ecpg itself does not do too much harm.

Michael
--
Michael Meskes
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