Probably bug in lib/regexec.c with possessive quantifier

[Egor Ignatov]

Hi,

So, after updating gnulib, some test cases in augeas(https://github.com/hercules-team/augeas) related to regex started to fail.
I found a commit that introduced this behavior:

70b673eb768eb7288639cbbe4642c2912b7d204e

I simplified the bug case to the following:

re_syntax_options = RE_CONTEXT_INDEP_OPS | RE_CONTEXT_INVALID_OPS | RE_DOT_NOT_NULL
                                 | RE_INTERVALS | RE_NO_BK_BRACES | RE_NO_BK_PARENS | RE_NO_BK_REFS
                                 | RE_NO_BK_VBAR | RE_NO_EMPTY_RANGES | RE_NO_POSIX_BACKTRACKING
                                 | RE_CONTEXT_INVALID_DUP | RE_NO_GNU_OPS;
pattern = "(.*+)";
text = "EXAMPLE";

And here is what I get in the regs after I run re_match:
match result: 'EXAMPLE'
reg[0]='EXAMPLE'(0,7)
reg[1]='EXAMPLE'(0,-1)
reg[2]=''(-1,-1)

But in the previous versions (before commit specified earlier) I would get:
match result: 'EXAMPLE'
reg[0]='EXAMPLE'(0,7)
reg[1]='EXAMPLE'(0,7)
reg[2]=''(-1,-1)

As you can see, in the first case reg[1] does not point to the first group.
However, everything works fine if I remove a possessive quantifier from the pattern.
Is this intentional behavior or is it a bug?

Thank you

-- 
Egor