[Boost-users] [xpressive] Stack overflow with small stacks without compiler optimization turned on

18 Nov 2011

      Hello *,

I currently ran into the issue with xpressive. One of our test suites
limits the stack usage to 32K and we have a stack overflow with over 600
function calls within xpressive. I stripped down our test case to the
minimally reproducible source:

#include 
#include <iostream>
#include <string>

using namespace boost::xpressive;
namespace x=boost::xpressive;
using namespace std;

const sregex allowed_chars = x::set[alnum | (x::set= '_','-','+','.')];

sregex regex(string const& delim)
{
  return
     bos                          // begin of sequence followed by
...
...
!(s1=as_xpr(delim))                // zero or one delimiter (greedy)
(s2=*(allowed_chars|as_xpr(delim)))// any number of allowed characters
mixed with delim string
;
}
int main()
{
  const string s = "Process.DiagBuffer";
  string delim;
  cout << "enter delim: ";
  cin >> delim;

  smatch what;
  bool matched = regex_match(s, what, regex(delim));
  const string suffix=what[s2];
  cout << suffix << endl;

  return 0;
}

Compilation Platform is Linux 32 bit.

Compiler call:
g++ -g -I"../software/boost_1_47_0" -o test main.cpp

For that source the stack has to be limited to 24K. You can set the stack
size and core dump file size like this:
$ ulimit -c 10000 -s 24

Consider using ulimit in the sub-shell, since stack size can't be increased
anymore.

If you are interested I can post the compiled executable and the core dump
file. When using optimization this works fine (it crashes with stack size
being less equal 12K), but the main question is: Is it really normal to
have more than 600 function calls in Debug mode?

Many thanks,
Ovanes

[Boost-users] [xpressive] Stack overflow with small stacks without compiler optimization turned on

Ovanes Markarian