Invalid C code generated with too-large array type

[tersec]

Description

discard sizeof(array[4611686018427387904, uint64])

Nim Version

Nim Compiler Version 2.0.14 [Linux: amd64]
Compiled at 2025-01-05
Copyright (c) 2006-2023 by Andreas Rumpf

git hash: bf4de6a394e040d9810cba8c69fb2829ff04dcc6
active boot switches: -d:release

Nim Compiler Version 2.2.0 [Linux: amd64]
Compiled at 2025-01-05
Copyright (c) 2006-2024 by Andreas Rumpf

git hash: 78983f1876726a49c69d65629ab433ea1310ece1
active boot switches: -d:release

Nim Compiler Version 2.3.1 [Linux: amd64]
Compiled at 2025-01-05
Copyright (c) 2006-2025 by Andreas Rumpf

git hash: e8bf6af0da52ce91dd0b5a7474d386d9a66809b9
active boot switches: -d:release

All with

gcc (Debian 14.2.0-12) 14.2.0

Current Output

error: size of array ‘tyArray__e7ovic9cojb5RXym3zh9aYIw’ exceeds maximum object size ‘9223372036854775807’
   30 | typedef NU64 tyArray__e7ovic9cojb5RXym3zh9aYIw[4611686018427387904];
      |              ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

Expected Output

No invalid C code generated

Known Workarounds

No response

Additional Information

No response

[Araq]

What's "too large"? How can we ensure the C compiler's idea agrees with our idea of too large?

[tersec]

https://stackoverflow.com/questions/42574890/why-is-the-maximum-size-of-an-array-too-large does suggest the C spec does not define this tightly enough to in general match the C compiler's behavior. There is a SIZE_MAX, but it isn't helpful here.

This doesn't look resolvable in a clean or portable way.

[demotomohiro]

How about to defining types larger than or equal to int.high + 1 or size of memory space (2^(pointer bit size)) is compile error?
9223372036854775807 (the number in the GCC error message) == int.high (2^63 - 1).
So making types larger than int.high is a compile error prevents the compile error from GCC.
Even if other C/C++ compilers has smaller type size limits, rejecting types larger than memory space makes sense.