Weird acceptation of here document

[Niols]

Consider the following here document:

cat <<EOF
a `b' c
d `e' f `g' h
EOF

Dash refuses it. I think it is probably the right thing to do. Morbig's parsing is quite weird anyway here:

[
    "Word",
    "a `b' c\nd `e' f `g' h\n",
    [
	[ "WordLiteral", "a " ],
	[
	    "WordSubshell",
	    [ "SubShellKindBackQuote" ],
	    [
		[...]

                "SimpleCommand_CmdName_CmdSuffix",
                [
		    "CmdName_Word",
		    [
			"Word",
			"b' c\nd `e'",
			[
			    [ "WordLiteral", "b" ],
			    [
				"WordSingleQuoted",
				[
				    "Word",
				    " c\nd `e",
				    [
					[
					    "WordLiteral",
					    " c\nd `e"
					]
				    ]
				]
			    ]
			]
		    ]
		],
		[
		    "CmdSuffix_Word",
		    [
			"Word",
			"f",
			[ [ "WordName", "f" ] ]
		    ]
		]
	    ]
	],
	[ "WordLiteral", "g' h\n" ]
    ]
]

How can g' h be a literal?