[Bug c++/112471] New: catch handler of type "reference to array" should be unreachable, but is reached

[arthur.j.odwyer at gmail dot com via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=112471

            Bug ID: 112471
           Summary: catch handler of type "reference to array" should be
                    unreachable, but is reached
           Product: gcc
           Version: 14.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c++
          Assignee: unassigned at gcc dot gnu.org
          Reporter: arthur.j.odwyer at gmail dot com
  Target Milestone: ---

// https://godbolt.org/z/W9P6GrG4x
#include <stdio.h>
int main() {
    try {
        throw nullptr;
    } catch (const int(&)[2]) {
        puts("caught int(&)[2]");
    } catch (const int*) {
        puts("caught int*");
    }
}

The correct output is "caught int*", because nullptr is not an array.
Clang and EDG produce the correct output.
MSVC is so confident that you can't throw an array (I think they're right!)
that it diagnoses the `catch` at -W4:

// https://godbolt.org/z/v6M1e5ff5
warning C4843: 'const int (&)[2]': An exception handler of reference to array
or function type is unreachable, use 'const int *' instead

GCC also mishandles unreachable catch handlers of type "reference to function":
again the correct output is "caught int*", Clang/EDG/MSVC all get it right, and
MSVC diagnoses.

// https://godbolt.org/z/sqoW6cPTn
    try {
        throw nullptr;
    } catch (int(&)()) {
        puts("caught int(&)()");
    } catch (const int*) {
        puts("caught int*");
    }