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//@ revisions: noopt opt opt_with_overflow_checks
//@[noopt]compile-flags: -C opt-level=0
//@[opt]compile-flags: -O
//@[opt_with_overflow_checks]compile-flags: -C overflow-checks=on -O
//@ build-pass
#![allow(arithmetic_overflow)]
use std::mem;
const fn assert_static<T>(_: &'static T) {}
// Function calls in const on the "main path" (not inside conditionals)
// do get promoted.
const fn make_thing() -> i32 {
42
}
const C: () = {
assert_static(&make_thing());
// Make sure this works even when there's other stuff (like function calls) above the relevant
// call in the const initializer.
assert_static(&make_thing());
};
fn main() {
assert_static(&["a", "b", "c"]);
assert_static(&["d", "e", "f"]);
// make sure that this does not cause trouble despite overflowing
assert_static(&(0u32 - 1));
// div-by-non-0 (and also not MIN/-1) is okay
assert_static(&(1/1));
assert_static(&(0/1));
assert_static(&(1/-1));
assert_static(&(i32::MIN/1));
assert_static(&(1%1));
// in-bounds array access is okay
assert_static(&([1, 2, 3][0] + 1));
assert_static(&[[1, 2][1]]);
// Top-level projections are not part of the promoted, so no error here.
if false {
#[allow(unconditional_panic)]
assert_static(&[1, 2, 3][4]);
}
// More complicated case involving control flow and a `#[rustc_promotable]` function
let decision = std::hint::black_box(true);
let x: &'static usize = if decision { &mem::size_of::<usize>() } else { &0 };
}
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