[Bug gdb/15934] New: Keep directories for argv[0]

[Bug gdb/15934] New: Keep directories for argv[0]

[jan.kratochvil at redhat dot com]

https://sourceware.org/bugzilla/show_bug.cgi?id=15934

            Bug ID: 15934
           Summary: Keep directories for argv[0]
           Product: gdb
           Version: HEAD
            Status: NEW
          Severity: minor
          Priority: P2
         Component: gdb
          Assignee: unassigned at sourceware dot org
          Reporter: jan.kratochvil at redhat dot com

Re: [commit+7.6.1] [patch] [7.6.1] Fix argv[0] symlink regression (PR 15415)
https://sourceware.org/ml/gdb-patches/2013-09/msg00138.html
Message-ID: <52276600.7010706@redhat.com>

   3    <null>            /home/pedro/gdb/mygit/build/gdb/./gdbserver/../gdb
   2    <null>            /home/pedro/gdb/mygit/build/gdb/./gdb

Problem #1: ./ could be removed/simplified.
Problem #2: gdbserver/../ could be also removed/simplified

But argv[0] should be kept possibly unchanged from the user input.
This also means argv[0] should be kept in relative (not absolute pathname)
form; but GDB should better display absolute pathnames to user, which will not
match argv[0] much.

Going to use gdb_realpath_keepfile() (former xfullpath()) so the directories
get lost even for inferior argv[0].  Inferiors care only about exact basename
in argv[0] anyway.

The goal of this PR fix would be to pass argv[0] unchanged to inferior while
still displaying it to user in both convenient (canonical absolute form) but
also the exact argv[0] form (original form, even if relative).

-- 
You are receiving this mail because:
You are on the CC list for the bug.

[Bug gdb/15934] Keep directories for argv[0]

[tromey at sourceware dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=15934

Tom Tromey <tromey at sourceware dot org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |tromey at sourceware dot org

--- Comment #1 from Tom Tromey <tromey at sourceware dot org> ---
I have a somewhat similar problem.

Suppose the user does 'file zzz', where zzz is a symlink.
Then, after running, the user resets the symlink to point to some
other file.

In this case, gdb won't change -- because the realpath'ing in
the objfile creation path will wind up resolving the symlink,
and so reread_symbols will think nothing has changed.

Locally this is complicated by the fact that we have a workaround
for the Windows gnulib/BFD stat mismatch bug in place.

I think my partial solution will be to remove OPF_RETURN_REALPATH
from symfile_bfd_open.

A full solution for this bug would probably involve storing the
user-specified name in the objfile and then changing various
spots in gdb to use that.  That is, the objfile would need one
name and the BFD would get another.

-- 
You are receiving this mail because:
You are on the CC list for the bug.

[Bug gdb/15934] Keep directories for argv[0]

[tromey at sourceware dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=15934

--- Comment #2 from Tom Tromey <tromey at sourceware dot org> ---
I suppose only the executable would need any special treatment.
But for that, I wonder how it would work in the startup-with-shell
case.  Without a shell, gdb can easily control argv[0].
With a shell, it seems harder, particularly if the executable
was specified relative to one working directory, but then
the cwd was changed in the gdb session.

-- 
You are receiving this mail because:
You are on the CC list for the bug.

[Bug gdb/15934] Keep directories for argv[0]

[tromey at sourceware dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=15934

--- Comment #3 from Tom Tromey <tromey at sourceware dot org> ---
See also bug #24143.  I have a patch that fixes that one
(basically what I wrote here in comment #1) and so gets this
one a little closer.

-- 
You are receiving this mail because:
You are on the CC list for the bug.

[Bug gdb/15934] Keep directories for argv[0]

[sam at gentoo dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=15934

Sam James <sam at gentoo dot org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |sam at gentoo dot org

-- 
You are receiving this mail because:
You are on the CC list for the bug.

[Bug gdb/15934] Keep directories for argv[0]

[sam at gentoo dot org]

https://sourceware.org/bugzilla/show_bug.cgi?id=15934

Sam James <sam at gentoo dot org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
           See Also|                            |https://sourceware.org/bugz
                   |                            |illa/show_bug.cgi?id=24143

-- 
You are receiving this mail because:
You are on the CC list for the bug.