bug#33115: 27.0.50; Add error-handling for comint-strip-ctrl-m

[Live System User]

Hi,

        Please consider adding additional error-handling for
        `comint-strip-ctrl-m'.

        Amongst other things, I set the following hook:


(add-hook 'comint-output-filter-functions 'comint-strip-ctrl-m)


        In my setup (i.e. NOT emacs -Q) I get the following
        error when exiting a *shell* process:


Debugger entered--Lisp error: (wrong-type-argument processp nil)
  process-mark(nil)
  comint-strip-ctrl-m("")
  run-hook-with-args(comint-strip-ctrl-m "")
  comint-send-input()
  funcall-interactively(comint-send-input)
  call-interactively(comint-send-input nil nil)
  command-execute(comint-send-input)


        Thanks.




In GNU Emacs 27.0.50 (build 46, x86_64-pc-linux-gnu, GTK+ Version 3.20.10)
 of 2018-10-14 built on localhost.localdomain
Repository revision: 6b8fd34c4ab1aa23b180440cdc8210900896bbf4
Windowing system distributor 'Fedora Project', version 11.0.11803000
System Description: Fedora 24 (Workstation Edition)

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Configured using:
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LCMS2 GMP

Important settings:
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Major mode: Summary

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