// ignore-windows: Windows does not have a global environ list that the program can access directly #[cfg(target_os="linux")] fn get_environ() -> *const *const u8 { extern "C" { static mut environ: *const *const u8; } unsafe { environ } } #[cfg(target_os="macos")] fn get_environ() -> *const *const u8 { extern "C" { fn _NSGetEnviron() -> *mut *const *const u8; } unsafe { *_NSGetEnviron() } } fn main() { let pointer = get_environ(); let _x = unsafe { *pointer }; std::env::set_var("FOO", "BAR"); let _y = unsafe { *pointer }; //~ ERROR dereferenced after this allocation got freed }