Recent change in master breaks EXWM

[Garjola Dindi]

Hi,

I build emacs from master every one or 2 weeks. Current master, produces
an error when loading EXWM. This is the backtrace:

Debugger entered--Lisp error: (cl-no-applicable-method xcb:-+request nil
  #<xcb:SetInputFocus xcb:SetInputFocus-157ae0c6dcd4>)
  signal(cl-no-applicable-method (xcb:-+request nil #<xcb:SetInputFocus
  xcb:SetInputFocus-157ae0c6dcd4>))
  cl-no-applicable-method(#s(cl--generic :name xcb:-+request :dispatches
  ((1 #s(cl--generic-generalizer :name cl--generic-t-generalizer
  :priority 0 :tagcode-function #f(compiled-function (name &rest _)
  #<bytecode -0x1cba0b13a96764e4>) :specializers-function
  #f(compiled-function (tag &rest _) #<bytecode -0x2b662d08469105e>)))
  (0 #s(cl--generic-generalizer :name eieio--generic-generalizer
  :priority 50 :tagcode-function cl--generic-struct-tag
  :specializers-function #f(compiled-function (tag &rest _) #<bytecode
  -0x10285462ecfcd9fd>)) #s(cl--generic-generalizer :name
  cl--generic-t-generalizer :priority 0 :tagcode-function
  #f(compiled-function (name &rest _) #<bytecode -0x1cba0b13a96764e4>)
  :specializers-function #f(compiled-function (tag &rest _) #<bytecode
  -0x2b662d08469105e>)))) :method-table (#s(cl--generic-method
  :specializers (xcb:connection t) :qualifiers nil :call-con nil
  :function #f(compiled-function (obj request) #<bytecode
  -0x6211ee00734115c>))) :options nil) nil #<xcb:SetInputFocus
  xcb:SetInputFocus-157ae0c6dcd4>) apply(cl-no-applicable-method
  #s(cl--generic :name xcb:-+request :dispatches ((1
  #s(cl--generic-generalizer :name cl--generic-t-generalizer :priority 0
  :tagcode-function #f(compiled-function (name &rest _) #<bytecode
  -0x1cba0b13a96764e4>) :specializers-function #f(compiled-function (tag
  &rest _) #<bytecode -0x2b662d08469105e>))) (0
  #s(cl--generic-generalizer :name eieio--generic-generalizer :priority
  50 :tagcode-function cl--generic-struct-tag :specializers-function
  #f(compiled-function (tag &rest _) #<bytecode -0x10285462ecfcd9fd>))
  #s(cl--generic-generalizer :name cl--generic-t-generalizer :priority 0
  :tagcode-function #f(compiled-function (name &rest _) #<bytecode
  -0x1cba0b13a96764e4>) :specializers-function #f(compiled-function (tag
  &rest _) #<bytecode -0x2b662d08469105e>)))) :method-table
  (#s(cl--generic-method :specializers (xcb:connection t) :qualifiers
  nil :call-con nil :function #f(compiled-function (obj request)
  #<bytecode -0x6211ee00734115c>))) :options nil) (nil
  #<xcb:SetInputFocus xcb:SetInputFocus-157ae0c6dcd4>))
  #f(compiled-function (&rest args) #<bytecode -0x45de7499ae3c765>)(nil
  #<xcb:SetInputFocus xcb:SetInputFocus-157ae0c6dcd4>)
  apply(#f(compiled-function (&rest args) #<bytecode
  -0x45de7499ae3c765>) nil #<xcb:SetInputFocus
  xcb:SetInputFocus-157ae0c6dcd4>) xcb:-+request(nil #<xcb:SetInputFocus
  xcb:SetInputFocus-157ae0c6dcd4>) exwm-input--exit() exwm-exit()
  exwm-init() run-hooks(window-setup-hook) #f(compiled-function ()
  #<bytecode -0x1efabd9733ee1e1>)() normal-top-level()

I don’t know how to debug this, but I am willing to try if someone gives
me directions. EXWM and its dependencies have not been updated for
months, as far as I can tell.

The emacs master branch compiled on July 8th does not produce this
error. My following build, on July 22nd, has the error. I could bissect
to identify the commit introducing the error, but maybe someone can
point me to a better strategy looking at the backtrace. Since the error
appears when loading EXWM, the only way to bissect entails recompiling
and restarting X, which is rather inconvenient and slow.

Also, I understand that this may not be a bug in Emacs, but rather a
need to update EXWM or xelb source code to keep up with Emacs'
evolutions, but my not knowing Elisp does not allow me to make the
difference.

Thanks in advance for your help.

Garjola.