Hi,
In 9.12 p164 General [dcl.dcl] 14882:2020(E) :

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12
A nodeclspec-function-declaration shall declare a constructor, destructor, or
conversion function.

[Note 3 : A nodeclspec-function-declaration can only be used in a
template-declaration (13.1), explicit-instantiation (13.9.3),
or explicit-specialization (13.9.4). — end note]
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nodeclspec-function-declaration :
     attribute-specifier-seqopt declarator ;


I don't understand Note 3.

What would an example be of a nodeclspec-function-declaration used in a
template-declaration ?