[Bug sanitizer/80498] New: Simple program with address sanitizer and regex hangs

[gcc at zutt dot org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80498

            Bug ID: 80498
           Summary: Simple program with address sanitizer and regex hangs
           Product: gcc
           Version: 6.3.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: sanitizer
          Assignee: unassigned at gcc dot gnu.org
          Reporter: gcc at zutt dot org
                CC: dodji at gcc dot gnu.org, dvyukov at gcc dot gnu.org,
                    jakub at gcc dot gnu.org, kcc at gcc dot gnu.org
  Target Milestone: ---

If I compile the below two files with "g++-6 -fsanitize=address a.cpp m.cpp"
and then run "./a.out", the program hangs forever, while without sanitize flag
it works as expected.

If I comment out the regex var 're' in m.cpp, the problem also disappears.

Is there some incompatibility with the regex library, and can that be solved or
can the library be excluded from checks?

I'm on macOS Sierra version 10.12.4 with g++-6 (Homebrew GCC 6.3.0_1) 6.3.0.

Thanks!

===

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

using namespace std;

void a(const std::string &s)
{
    regex re_a("foo (.+)");
    smatch pieces;

    if (regex_match(s, pieces, re_a))
    {
        cout << "foo with " << pieces[1].str() << endl;
    }
}

// m.cpp
#include <string>
#include <regex>

void a(const std::string &s);

int main(int argc, char** argv)
{
    std::regex re("123");

    a("foo test 123");
}