Report from the additional type errors for GCC 14 BoF at Cauldron

[Florian Weimer via Gcc]

My understanding of the consensus goes as follows:

* We want to make some changes in this area for GCC 14.
* We should do the same thing that Clang does: default to the relevant
  -Werror= options.
* Unlike regular warnings, these warnings-as-errors should also apply
  to system headers.
* At least implict-int and implicit-function-declaration should be
  upgraded to errors in this way.
* It's too early to make the () changes and bool-as-keyword from C2X
  for GCC 14.
* We should fix the missing scope of the int-conversion warnings
  (PR109827).  Likweise for incompatible-pointer-types (PR109826).

Is this summary accurate?

I think the open issues are:

* Do we want to implement something else beside implicit-int and
  implicit-function-declaration?  (Candidates are int-conversion and
  incompatible-pointer-types, and the void vs non-void part of
  return-type, maybe others as previously discussed on the list.)
* How do we divide up the test suite cleanup work?

Thanks,
Florian