#[repr(C)] struct ReallyBig { _a: [u8; usize::MAX], } // The limit for "too big for the current architecture" is dependent on the target pointer size // however it's artificially limited on 64 bits // logic copied from rustc_target::abi::TargetDataLayout::obj_size_bound() const fn max_size() -> usize { #[cfg(target_pointer_width = "16")] { 1 << 15 } #[cfg(target_pointer_width = "32")] { 1 << 31 } #[cfg(target_pointer_width = "64")] { 1 << 47 } #[cfg(not(any( target_pointer_width = "16", target_pointer_width = "32", target_pointer_width = "64" )))] { isize::MAX as usize } } extern "C" { static FOO: [u8; 1]; static BAR: [u8; max_size() - 1]; static BAZ: [u8; max_size()]; //~ ERROR extern static is too large static UWU: [usize; usize::MAX]; //~ ERROR extern static is too large static A: ReallyBig; //~ ERROR extern static is too large } fn main() {}