Re: [Grep-devel] [platform-testers] new snapshot available: grep-3.1.46-504af

[Jim Meyering]

On Sat, Dec 15, 2018 at 11:53 AM Bruno Haible <address@hidden> wrote:
>
> Assaf Gordon wrote:
> > "backref-alt" test fails on several systems:
> >    Ubuntu 14.04 (aarch64)
> >    Raspbian 9.6 (armv7l)
> >    Debian 8.11 (mips64)
> >    Debian 8.11 (i686)
> > (perhaps something to do with non-amd64 systems?)
>
> I see it also fail on Ubuntu 16.04 (x86_64). test-suite.log contains this:
>
>
> FAIL: backref-alt
> =================
...
>
> regexec.c comes from libc. libc is glibc version 2.23-0ubuntu10.

Thanks to both of you for all the speedy testing!

> I guess the fix should be to detect the glibc bug in m4/regex.m4 ?

Exactly. That's what I'm doing now.
I'm expecting to insert something like this, probably reusing the
result value of "64":

            /* Matching with the compiled form of this regexp would
provoke
               an assertion failure prior to glibc-2.28:
                 regexec.c:1375: pop_fail_stack: Assertion `num >= 0'
failed
               With glibc-2.28, compilation fails and reports the
invalid
               back reference.  */
            re_set_syntax (RE_SYNTAX_POSIX_EGREP);
            memset (&regex, 0, sizeof regex);
            s = re_compile_pattern ("0|()0|\\1|0", 10, &regex);
            if (!s || strcmp (s, "Invalid back reference"))
              result |= 64;