Re: segfault in incremental build mode with partial files

[Shigio YAMAGUCHI]

Hello,
Could you please send me a reproduction environment without
vim-related files? Thank you in advance.

Regards,
Shigio

On Mon, Jul 29, 2024 at 12:03 AM Scott Mcdermott <scott@smemsh.net> wrote:
>
> This is to report a crash and segfault when running gtags
> in incremental mode.
>
> My editor is configured to run gtags in all git repos.  It's crashing
> when I edit in my ~/.vim/ directory, which is a checkout of
> https://github.com/smemsh/.vim/ repo (config file is "gtags.conf"
> therein).  This gtags was built in May of this year from the
> then-current trunk.  I checked and it looks like no crash fixes
> have been committed since. System is Ubuntu22 on x86_64.
>
> This problem went away when I removed the existing files
> (so it was non-incremental).  The tags update script has a trap
> to remove partials if no finish (editor exits before gtags finishes,
> process group is killed), but the update wrapper has race
> conditions so it probably didn't work and the file generation was
> incomplete.
>
> Nonetheless, gtags still should not crash.
>
> Let me know if more information is needed (i.e., build with -g, or
> upload the partials -- which I saved -- somewhere).
>
> See below; eom.
>
>  $ cd var/vim/tags/home-scott-.vim
>
>  $ lsa
> -rw-r--r-- 1 1001 666 2.0M 20240712000626 GPATH
> -rw-r--r-- 1 1001 666 4.1M 20240712055818 GRTAGS
> -rw-r--r-- 1 1001 666 338M 20240712055818 GTAGS
>
>  $ gdb -q -d ~/upsrc/global --args `which gtags` --incremental 
> /home/scott/var/vim/tags/home-scott-.vim
> Reading symbols from /usr/local/bin/gtags...
> (gdb) r
> Starting program: /usr/local/bin/gtags --incremental 
> /home/scott/var/vim/tags/home-scott-.vim
> [Thread debugging using libthread_db enabled]
> Using host libthread_db library "/lib/x86_64-linux-gnu/libthread_db.so.1".
> [Detaching after fork from child process 4066050]
> [Detaching after fork from child process 4066053]
> [Detaching after fork from child process 4066054]
>
> Program received signal SIGSEGV, Segmentation fault.
> __bt_dleaf (t=t@entry=0x555555694920, key=key@entry=0x0, 
> h=h@entry=0x55555588a630, index=0) at bt_delete.c:507
> 507                     ip[0] = ip[1] < offset ? ip[1] + nbytes : ip[1];
> (gdb) bt
> #0  __bt_dleaf (t=t@entry=0x555555694920, key=key@entry=0x0, 
> h=h@entry=0x55555588a630, index=0) at bt_delete.c:507
> #1  0x0000555555609515 in __bt_delete (dbp=<optimized out>, key=<optimized 
> out>, flags=<optimized out>) at bt_delete.c:114
> #2  0x0000555555573356 in dbop_delete (dbop=<optimized out>, 
> path=path@entry=0x0) at dbop.c:506
> #3  0x0000555555578ce3 in gtags_delete (gtop=0x555555693660, 
> deleteset=deleteset@entry=0x55555565a090) at gtagsop.c:592
> #4  0x000055555556553f in updatetags (dbpath=dbpath@entry=0x7fffffffc1f0 
> "/home/scott/var/vim/tags/home-scott-.vim",
>     root=root@entry=0x7fffffffd1f0 "/home/scott/.vim", 
> deleteset=deleteset@entry=0x55555565a090, 
> addlist=addlist@entry=0x55555567e680) at gtags.c:957
> #5  0x0000555555565aa1 in incremental (dbpath=dbpath@entry=0x7fffffffc1f0 
> "/home/scott/var/vim/tags/home-scott-.vim",
>     root=root@entry=0x7fffffffd1f0 "/home/scott/.vim") at gtags.c:808
> #6  0x00005555555647c0 in main (argc=<optimized out>, argv=<optimized out>) 
> at gtags.c:576



-- 
Shigio YAMAGUCHI <shigio@gnu.org>
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