[Bug tree-optimization/81679] use attribute unused on function arguments as an optimization hint

[msebor at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=81679

Martin Sebor <msebor at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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             Status|WAITING                     |UNCONFIRMED
     Ever confirmed|1                           |0

--- Comment #7 from Martin Sebor <msebor at gcc dot gnu.org> ---
It's the feature that I think would be useful.  The name of the new attribute
itself or its placement are secondary, although being able to repurpose the
intuitive name "unused" would be nice.  If applying attribute unused to
parameters wouldn't work then making unused a function attribute might be an
alternative, like so:

  __attribute__ ((unused (1))) void f (void*);

meaning the first parameter isn't used by the function definition.