[Bug c++/119180] GCC Accepts Non-Standard Variable-Length Arrays (VLAs) in C++ Without Warnings

[pinskia at gcc dot gnu.org via Gcc-bugs]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=119180

--- Comment #3 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
>with -pedantic warns but still succeeds

You need -pedantic-errors.