Fix locations of shadowing warnings in ms_transform

A shadowed variable in an ms_transform match expression emits a warning
located at the match expression instead of the variable.
Optimise io requests for long message queues

Ensure that the monitor reference is present in all receive clauses, so
that the compiler optimisation kicks in and the run time won't depend on
the length of the message queue of the calling process.

Remove the 'EXIT' clause, as its presence breaks the optimisation, and
that case is handled by the 'DOWN' clause anyway.

The test io_SUITE:io_with_huge_message_queue is an adaptation of
gen_server_SUITE:call_with_huge_message_queue.
stdlib: fix a bug in qlc_SUITE.erl
Fix miscompilation when module contains multiple named funs

A module containing two named funs bearing the same name and arity could be
miscompiled.

Reported-by: Sam Chapin
Remove comments about unicode atoms in OTP 18

There was once a plan to implement support for unicode atoms in OTP
18. This plan has been stopped until further notice, and the
information about this is now removed from the documentation.
Merge branch 'hb/stdlib/fix_qlc_test'

* hb/stdlib/fix_qlc_test:
  stdlib: fix a bug in qlc_SUITE.erl
Merge branch 'nox/compiler/eep37-duplicate-names/OTP-12262' into maint

* nox/compiler/eep37-duplicate-names/OTP-12262:
  Fix miscompilation when module contains multiple named funs
Merge branch 'nox/stdlib/ms_transform-locate-shadow-warning/OTP-12264' into maint

* nox/stdlib/ms_transform-locate-shadow-warning/OTP-12264:
  Fix locations of shadowing warnings in ms_transform
Merge branch 'maint'

* maint:
  Fix miscompilation when module contains multiple named funs
  Fix locations of shadowing warnings in ms_transform
Merge branch 'siri/no-unicode-atoms/OTP-12172' into maint

* siri/no-unicode-atoms/OTP-12172:
  Remove comments about unicode atoms in OTP 18
Merge branch 'maint'
erl_tar: Extend api to define own storage media access functions.

The reason for this is a requirement on enabling ssh_sftp to write a tar file on the server.
This new api function is used by ssh_sftp:open_tar/3,4.
ssh: Add ssh_sftp:open_tar/3,4 which opens a tar file at the server side of a channel.

Depends on erl_tar.erl having the function erl_tar:init/3 defined.
ssh: update vsn.mk
Merge branch 'hans/ssh/erl_tar_sftp/OTP-12180' into maint

* hans/ssh/erl_tar_sftp/OTP-12180:
  ssh: update vsn.mk
  ssh: Add ssh_sftp:open_tar/3,4 which opens a tar file at the server side of a channel.
  erl_tar: Extend api to define own storage media access functions.
Merge branch 'maint'
Update file.xml

Fix grammatical errors in section on file:datasync/1
stdlib: remove the last traces of Mnemosyne Rules

Robert has OK'ed the removal of the token ':-'.
Merge branch 'hb/stdlib/remove_rule_syntax/OTP-12257'

* hb/stdlib/remove_rule_syntax/OTP-12257:
  stdlib: remove the last traces of Mnemosyne Rules
Merge branch 'marcsugiyama/patch-1/doc-fix'

* marcsugiyama/patch-1/doc-fix:
  Update file.xml