Author: ph10 Date: To: pcre-dev CC: Daniel Richard G. Subject: Re: [pcre-dev] [PATCH] PCRE2 on Windows
On Thu, 19 Apr 2018, I wrote:
> > * Test 6 still crashes due to running out of stack space, only in this
> > case, it's a very deep call stack that is the issue. I had to add
> > /STACK:3000000 to the linker invocation for this issue to go away.
>
> This is DFA matching again. On Linux it runs with a 2MB stack on my box.
> The Linux default is 8MB and I continue to be amazed that in these days
> of gigabyte memories, default stack sizes are so small. Not sure what to
> do about this yet, either. As you might know, pcre2_match() was recently
> refactored so as not to make much use of the stack. Perhaps something
> drastic along the same lines is needed for pcre2_dfa_match(). Added to
> the "think about" list.
I thought about it. I have just committed a patch (r932) which
re-factors pcre2_dfa_match() such that it uses the heap for internal
workspace vectors if more than an initial 30K vector on the stack is
needed. This reduces the stack requirements and on my Linux box test 6
runs with a 1Mb stack now.
If you get a chance, please can you try this code to see if it fixes
your problems on Windows. I think it will, because you had it working
with reduced stack vector sizes and I have completely removed those
vectors from the stack. There is a performance hit, but only if the
pattern contains recursions, lookarounds, or atomic groups.
That leaves only the Ctrl/Z issue. Since I can't remember why it's
there, I think I will just change it to some other character.
