closing '}' misplaced in here-document in function

[Denis McKeon]

Configuration Information [Automatically generated, do not change]:
Machine: x86_64
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS: -O2 -g -pipe -Wall -Werror=format-security 
-Wp,-D_FORTIFY_SOURCE=2 -Wp,-D_GLIBCXX_ASSERTIONS -fexceptions 
-fstack-protector-strong -grecord-gcc-switches 
-specs=/usr/lib/rpm/redhat/redhat-hardened-cc1 
-specs=/usr/lib/rpm/redhat/redhat-annobin-cc1 -m64 -mtune=generic 
-fasynchronous-unwind-tables -fstack-clash-protection -fcf-protection 
-Wno-parentheses -Wno-format-security
uname output: Linux dt1 5.1.12-300.fc30.x86_64 #1 SMP Wed Jun 19 
15:19:49 UTC 2019 x86_64 x86_64 x86_64 GNU/Linux
Machine Type: x86_64-redhat-linux-gnu

Bash Version: 5.0
Patch Level: 7
Release Status: release

Description:

    Bash appears to move the closing '}'
    from after a closing here-document delimiter
    to the start of the here-doc body
    (just after the opening here-document delimiter)
    in a function definition contained within
    another function definition.

    This conflicts with later invocations of /bin/sh , like:

        $ /bin/sh
        sh: demo: line 22: syntax error: unexpected end of file
        sh: error importing function definition for `demo'

    Workaround:
        assign the text within the here-doc to a variable.

Repeat-By:

    #!/bin/bash
    bash --version 2>&1 | head -1
    demo () {
        # problem
        function sub () { cat<<'EOFsub'
            sub
    EOFsub
        }       # this brace is moved to just after <<'EOFsub'
        # workaround
        function var () { local var="$(cat<<'EOFvar'
            var
    EOFvar
    )"
        echo "$var"
        };
    cat<<EOF
            demo
    EOF
    # invoke sub-functions
    sub;
    var
    }
    declare -f -x demo
    # display function definitions with moved '}'
    typeset -f -p demo
    # invoke main function
    demo