I tested in 5.8.7, not 5.8.8, but I saw the same results. I tested a few other things about X::a, but I can't see why the debugger gets confused.

One clue as to what's going on might be in the perl -MO=Deparse output: 

package X;
sub BEGIN {
    require strict;
    do {
        'strict'->import
    };
}
use Attribute::Handlers;
sub a {
    use strict 'refs';
    print "a\n";
}
use attributes ('X', sub {
    use strict 'refs';
    print "a\n";
}
, 'ATTR(SCALAR)');
sub b {
    use strict 'refs';
    print "b\n";
}
package main;
use strict 'refs';
X::a();
X::b();

[download]
The use attributes after sub a is interesting. If it reassigned *X::a that could explain weird behaviour, but it doesn't. Interesting!

Adding a call to a routine that prints "caller" info instead of the print statements in a and b shows that the caller info is sane, and matches the expected line numbers.


Mike

In reply to Re: bug in the debugger? breakpoints in subroutines ignored if attributes present by RMGir
in thread bug in the debugger? breakpoints in subroutines ignored if attributes present by wu-lee

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.