bug#55832: 28.1; Emacs crashes when using tramp from helm in emacs-29

[Eli Zaretskii <eliz@gnu.org>]

> From: Thierry Volpiatto <thievol@posteo.net>
> Cc: larsi@gnus.org, 55832@debbugs.gnu.org
> Date: Thu, 09 Jun 2022 16:51:18 +0000
> 
> (gdb) source /home/thierry/tmp/emacs/src/.gdbinit
> SIGINT is used by the debugger.
> Are you sure you want to change it? (y or n) [answered Y; input not from terminal]
> DISPLAY = :0.0
> TERM = xterm-256color
> Breakpoint 1 at 0x5555555a6b56: file emacs.c, line 420.
> Breakpoint 2 at 0x5555556ba640: file xterm.c, line 22325.
> (gdb) frame 8
> #8  0x00005555557ac8a3 in call2 (arg2=XIL(0x55555a4b2e83), arg1=XIL(0x90), fn=<optimized out>) at lisp.h:3232
> 3232      return CALLN (Ffuncall, fn, arg1, arg2);
> (gdb) p arg2
> $1 = XIL(0x55555a4b2e83)
> (gdb) xtype
> Lisp_Cons
> (gdb) xlist
> No symbol "builtin_lisp_symbol" in current context.
> (gdb) p arg1
> $2 = XIL(0x90)
> (gdb) xtype
> Lisp_Symbol
> (gdb) xsymbol
> $3 = (struct Lisp_Symbol *) 0x555555cd6cd0 <lispsym+144>
> "error"
> (gdb) frame 103105
> #103105 0x00005555557ab8be in Ffuncall (nargs=4, args=0x7fffffd15a80) at eval.c:2953
> 2953      Lisp_Object val = funcall_general (args[0], nargs - 1, args + 1);
> (gdb) p args[0]
> $4 = XIL(0x23a93f0)
> (gdb) xtype
> Lisp_Symbol
> (gdb) xsymbol
> $5 = (struct Lisp_Symbol *) 0x555558080030
> "tramp-file-name-for-operation"
> (gdb) p args[1]
> $6 = XIL(0x22fdb90)
> (gdb) xtype
> Lisp_Symbol
> (gdb) xsymbol
> $7 = (struct Lisp_Symbol *) 0x555557fd47d0
> "tramp-get-remote-uid"
> (gdb) p args[2]
> $8 = XIL(0x55555a7df8c3)
> (gdb) xtype
> Lisp_Cons
> (gdb) xlist
> No symbol "builtin_lisp_symbol" in current context.
> (gdb) p args[3]
> $9 = XIL(0xe940)
> (gdb) xtype
> Lisp_Symbol
> (gdb) xsymbol
> $10 = (struct Lisp_Symbol *) 0x555555ce5580 <lispsym+59712>
> "string"

So tramp-file-name-for-operation errors out, and that somehow gets us
in trouble.

I see we call signal-hook-function -- what is its value in that
session, please?