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//@ edition: 2018
#![unstable(feature = "humans",
reason = "who ever let humans program computers,
we're apparently really bad at it",
issue = "none")]
#![feature(foo, foo2)]
#![feature(const_async_blocks, staged_api, rustc_attrs)]
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_unstable(feature="foo", issue = "none")]
const fn foo() -> u32 { 42 }
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_stable(feature = "rust1", since = "1.0.0")]
// can't call non-min_const_fn
const fn bar() -> u32 { foo() } //~ ERROR cannot use `#[feature(foo)]`
#[unstable(feature = "foo2", issue = "none")]
#[rustc_const_unstable(feature = "foo2", issue = "none")]
const fn foo2() -> u32 { 42 }
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_stable(feature = "rust1", since = "1.0.0")]
// can't call non-min_const_fn
const fn bar2() -> u32 { foo2() } //~ ERROR cannot use `#[feature(foo2)]`
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_stable(feature = "rust1", since = "1.0.0")]
// conformity is required
const fn bar3() -> u32 {
let x = async { 13 };
//~^ ERROR cannot use `#[feature(const_async_blocks)]`
foo()
//~^ ERROR cannot use `#[feature(foo)]`
}
// check whether this function cannot be called even with the feature gate active
#[unstable(feature = "foo2", issue = "none")]
#[rustc_const_unstable(feature = "foo2", issue = "none")]
const fn foo2_gated() -> u32 { 42 }
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_stable(feature = "rust1", since = "1.0.0")]
// can't call non-min_const_fn
const fn bar2_gated() -> u32 { foo2_gated() } //~ ERROR cannot use `#[feature(foo2)]`
// Functions without any attribute are checked like stable functions,
// even if they are in a stable module.
mod stable {
#![stable(feature = "rust1", since = "1.0.0")]
pub(crate) const fn bar2_gated_stable_indirect() -> u32 { super::foo2_gated() } //~ ERROR cannot use `#[feature(foo2)]`
}
// And same for const-unstable functions that are marked as "stable_indirect".
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_unstable(feature="foo", issue = "none")]
#[rustc_const_stable_indirect]
const fn stable_indirect() -> u32 { foo2_gated() } //~ ERROR cannot use `#[feature(foo2)]`
// These functiuons *can* be called from fully stable functions.
#[stable(feature = "rust1", since = "1.0.0")]
#[rustc_const_stable(feature = "rust1", since = "1.0.0")]
const fn bar2_gated_exposed() -> u32 {
stable::bar2_gated_stable_indirect() + stable_indirect()
}
fn main() {}
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