Caveat re VLAs: while C23 doesn’t return VLAs to mandatory status, it does require variably modified types; so no stack space footgun but still a significant co

Caveat re VLAs: while C23 doesn’t return VLAs to mandatory status, it does require variably modified types; so no stack space footgun but still a significant complication in the type system: void foo(size_t n) { int a[n][n]; } does not have to be supported outside C99 but void bar(size_t n, void *p) { int (*pa)[n][n] = p; } has to be in both C99 and C23 (though not in C11 or C17).