Segfaulting VIM. What?

I got quite the surprise today while opening a file for editing using vim.

fx@teikapi2:~ sudo vim /etc/hosts  
Segmentation fault  

Say what? Vim, segfaulting? Okay.

There was an automatic apt-get upgrade on this machine today, so that is the explanation.
Still quite weird and most definitely not expected.

Quick backtrace under gdb showed:

#0  _dl_lookup_symbol_x (undef_name=0x40a93987 <error: Cannot access memory at address 0x40a93987>, undef_map=undef_map@entry=0x76fff958, ref=ref@entry=0x7efff3ec,
    symbol_scope=symbol_scope@entry=0x76fffb10, version=0x76d1e500, type_class=1, flags=flags@entry=1, skip_map=skip_map@entry=0x0) at dl-lookup.c:715
#1  0x76fdb31c in elf_machine_rel (reloc=0x54abe014, skip_ifunc=<optimized out>, reloc_addr_arg=0x54c7f4a0, version=<optimized out>, sym=0x54b2c384, map=0x76fff958)
    at ../ports/sysdeps/arm/dl-machine.h:377
#2  elf_dynamic_do_Rel (skip_ifunc=<optimized out>, lazy=0, nrelative=<optimized out>, relsize=<optimized out>, reladdr=<optimized out>, map=0x76fff958) at do-rel.h:137
#3  _dl_relocate_object (scope=<optimized out>, reloc_mode=<optimized out>, consider_profiling=<optimized out>, consider_profiling@entry=0) at dl-reloc.c:264
#4  0x76fd23a4 in dl_main (phdr=<optimized out>, phnum=<optimized out>, user_entry=<optimized out>, auxv=<optimized out>) at rtld.c:2201
#5  0x76fe5b30 in _dl_sysdep_start (start_argptr=start_argptr@entry=0x7efff800, dl_main=0x0) at ../elf/dl-sysdep.c:249
#6  0x76fd3c78 in _dl_start_final (arg=0x7efff800, arg@entry=0x0, info=info@entry=0x7efff580) at rtld.c:330
#7  0x76fd3f08 in _dl_start (arg=0x0) at rtld.c:558
#8  0x76fcfd50 in _start () from /lib/ld-linux-armhf.so.3

So looks like a fail whilst doing ELF dynamic relocation.

Somewhat regretfully, I reinstalled vim and this fixed the problem.

Now, in retrospect, should have saved the binary.
The more I think about it the more interesting this seems.

System testing after upgrades seems like a good idea at this point, ofc that would be an overkill for my poor raspberry Pi that servers mainly as a Samba server at home 🙂

More digging next time, eh?