This was always a weird feature, and isn't being used in the compiler.
Static assertions should be done better than this.
This implements RFC #1096.
Fixes #13951
Fixes #23008
Fixes #6676
This is behind a feature gate, but that's still a
[breaking-change]
- `simd` - on certain tuple structs, derive the arithmetic operators, which
lower to the target's SIMD instructions, if any; the `simd` feature gate
is necessary to use this attribute.
-- `static_assert` - on statics whose type is `bool`, terminates compilation
- with an error if it is not initialized to `true`. To use this, the `static_assert`
- feature gate must be enabled.
- `unsafe_no_drop_flag` - on structs, remove the flag that prevents
destructors from being run twice. Destructors might be run multiple times on
the same object with this attribute. To use this, the `unsafe_no_drop_flag` feature
crate. Stability markers are also attributes: `#[stable]`,
`#[unstable]`, and `#[deprecated]` are the three levels.
-* `static_assert` - The `#[static_assert]` functionality is experimental and
- unstable. The attribute can be attached to a `static` of
- type `bool` and the compiler will error if the `bool` is
- `false` at compile time. This version of this functionality
- is unintuitive and suboptimal.
-
* `start` - Allows use of the `#[start]` attribute, which changes the entry point
into a Rust program. This capability, especially the signature for the
annotated function, is subject to change.
let g = consts::trans_static(ccx, m, item.id);
update_linkage(ccx, g, Some(item.id), OriginalTranslation);
-
- // Do static_assert checking. It can't really be done much earlier
- // because we need to get the value of the bool out of LLVM
- if attr::contains_name(&item.attrs, "static_assert") {
- if !ty::type_is_bool(ty::expr_ty(ccx.tcx(), expr)) {
- ccx.sess().span_fatal(expr.span,
- "can only have static_assert on a static \
- with type `bool`");
- }
- if m == ast::MutMutable {
- ccx.sess().span_fatal(expr.span,
- "cannot have static_assert on a mutable \
- static");
- }
-
- let v = ccx.static_values().borrow().get(&item.id).unwrap().clone();
- unsafe {
- if !(llvm::LLVMConstIntGetZExtValue(v) != 0) {
- ccx.sess().span_fatal(expr.span, "static assertion failed");
- }
- }
- }
},
ast::ItemForeignMod(ref foreign_mod) => {
foreign::trans_foreign_mod(ccx, foreign_mod);
// Allows the use of rustc_* attributes; RFC 572
("rustc_attrs", "1.0.0", Active),
- // Allows the use of `static_assert`
- ("static_assert", "1.0.0", Active),
-
// Allows the use of #[allow_internal_unstable]. This is an
// attribute on macro_rules! and can't use the attribute handling
// below (it has to be checked before expansion possibly makes
("no_builtins", Whitelisted),
("no_mangle", Whitelisted),
("no_stack_check", Whitelisted),
- ("static_assert", Gated("static_assert",
- "`#[static_assert]` is an experimental feature, and has a poor API")),
("no_debug", Whitelisted),
("omit_gdb_pretty_printer_section", Whitelisted),
("unsafe_no_drop_flag", Gated("unsafe_no_drop_flag",
+++ /dev/null
-// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#[static_assert] //~ ERROR `#[static_assert]` is an experimental feature
-static X: bool = true;
-
-fn main() {}
+++ /dev/null
-// Copyright 2015 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#![feature(static_assert)]
-#![allow(dead_code)]
-
-#[static_assert]
-static E: i32 = 1; //~ ERROR can only have static_assert on a static with type `bool`
-
-fn main() {}
+++ /dev/null
-// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#![feature(static_assert)]
-#![allow(dead_code)]
-
-#[static_assert]
-static A: bool = false; //~ ERROR static assertion failed
-
-fn main() {
-}
+++ /dev/null
-// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-#![feature(static_assert)]
-#![allow(dead_code)]
-
-#[static_assert]
-static E: bool = 1 == 2; //~ ERROR static assertion failed
-
-fn main() {}
+++ /dev/null
-// Copyright 2014 The Rust Project Developers. See the COPYRIGHT
-// file at the top-level directory of this distribution and at
-// http://rust-lang.org/COPYRIGHT.
-//
-// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
-// http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
-// <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
-// option. This file may not be copied, modified, or distributed
-// except according to those terms.
-
-// pretty-expanded FIXME #23616
-
-#![feature(static_assert)]
-
-#[static_assert]
-static b: bool = true;
-
-#[static_assert]
-static c: bool = 1 == 1;
-
-#[static_assert]
-static d: bool = 1 != 2;
-
-#[static_assert]
-static f: bool = (4/2) == 2;
-
-pub fn main() {
-}