also make library/std work

Author: RalfJung

library/std/src/lib.rs

@@ -414,8 +414,24 @@
 //
 #![default_lib_allocator]
 
+// We want to be able to `cargo miri test` this crate, but that's tricky.
+// We use the `miri-test` feature to indicate that we're running `cargo miri test`, and
+// with that feature we turn this crate into a re-export of the sysroot crate. We only do this when
+// building the crate that will become a dependency, not when doing the actual (doc)test build.
+// See `core/src/lib.rs` for more information.
+#[cfg(not(any(not(feature = "miri-test"), test, doctest)))]
+extern crate std as realstd;
+#[cfg(not(any(not(feature = "miri-test"), test, doctest)))]
+#[stable(feature = "miri_test_libstd", since = "1.0.0")]
+pub use realstd::*;
+
+// Otherwise, we build the crate as usual. To avoid having to repeat the same `cfg` so many times,
+// we `include!("lib_.rs")` with the main crate contents, and `cfg` the `include!`. However, some
+// macro-related things can't be behind the `include!` so we have to repeat the `cfg` for them.
+
 // Explicitly import the prelude. The compiler uses this same unstable attribute
 // to import the prelude implicitly when building crates that depend on std.
+#[cfg(not(all(feature = "miri-test", not(any(test, doctest)))))]
 #[prelude_import]
 #[allow(unused)]
 use prelude::rust_2021::*;
@@ -424,14 +440,17 @@ use prelude::rust_2021::*;
 #[cfg(test)]
 extern crate test;
 
+#[cfg(not(all(feature = "miri-test", not(any(test, doctest)))))]
 #[allow(unused_imports)] // macros from `alloc` are not used on all platforms
 #[macro_use]
 extern crate alloc as alloc_crate;
+#[cfg(not(all(feature = "miri-test", not(any(test, doctest)))))]
 #[doc(masked)]
 #[allow(unused_extern_crates)]
 extern crate libc;
 
 // We always need an unwinder currently for backtraces
+#[cfg(not(all(feature = "miri-test", not(any(test, doctest)))))]
 #[doc(masked)]
 #[allow(unused_extern_crates)]
 extern crate unwind;
@@ -441,6 +460,7 @@ extern crate unwind;
 // Remove exclusion from tidy platform check when this removed.
 #[doc(masked)]
 #[allow(unused_extern_crates)]
+#[cfg(not(all(feature = "miri-test", not(any(test, doctest)))))]
 #[cfg(all(
     not(all(windows, target_env = "msvc", not(target_vendor = "uwp"))),
     feature = "miniz_oxide"
@@ -457,286 +477,23 @@ extern crate miniz_oxide;
 extern crate std as realstd;
 
 // The standard macros that are not built-in to the compiler.
+#[cfg(not(all(feature = "miri-test", not(any(test, doctest)))))]
 #[macro_use]
 mod macros;
 
 // The runtime entry point and a few unstable public functions used by the
 // compiler
+#[cfg(not(all(feature = "miri-test", not(any(test, doctest)))))]
 #[macro_use]
 pub mod rt;
 
 // The Rust prelude
+#[cfg(not(all(feature = "miri-test", not(any(test, doctest)))))]
 pub mod prelude;
 
-// Public module declarations and re-exports
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use alloc_crate::borrow;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use alloc_crate::boxed;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use alloc_crate::fmt;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use alloc_crate::format;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use alloc_crate::rc;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use alloc_crate::slice;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use alloc_crate::str;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use alloc_crate::string;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use alloc_crate::vec;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::any;
-#[stable(feature = "core_array", since = "1.36.0")]
-pub use core::array;
-#[unstable(feature = "async_iterator", issue = "79024")]
-pub use core::async_iter;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::cell;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::char;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::clone;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::cmp;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::convert;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::default;
-#[stable(feature = "futures_api", since = "1.36.0")]
-pub use core::future;
-#[stable(feature = "core_hint", since = "1.27.0")]
-pub use core::hint;
-#[stable(feature = "i128", since = "1.26.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::i128;
-#[stable(feature = "rust1", since = "1.0.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::i16;
-#[stable(feature = "rust1", since = "1.0.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::i32;
-#[stable(feature = "rust1", since = "1.0.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::i64;
-#[stable(feature = "rust1", since = "1.0.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::i8;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::intrinsics;
-#[stable(feature = "rust1", since = "1.0.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::isize;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::iter;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::marker;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::mem;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::ops;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::option;
-#[stable(feature = "pin", since = "1.33.0")]
-pub use core::pin;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::ptr;
-#[stable(feature = "rust1", since = "1.0.0")]
-pub use core::result;
-#[stable(feature = "i128", since = "1.26.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::u128;
-#[stable(feature = "rust1", since = "1.0.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::u16;
-#[stable(feature = "rust1", since = "1.0.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::u32;
-#[stable(feature = "rust1", since = "1.0.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::u64;
-#[stable(feature = "rust1", since = "1.0.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::u8;
-#[stable(feature = "rust1", since = "1.0.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::usize;
-
-pub mod f32;
-pub mod f64;
-
+#[cfg(not(all(feature = "miri-test", not(any(test, doctest)))))]
 #[macro_use]
 pub mod thread;
-pub mod ascii;
-pub mod backtrace;
-pub mod collections;
-pub mod env;
-pub mod error;
-pub mod ffi;
-pub mod fs;
-pub mod hash;
-pub mod io;
-pub mod net;
-pub mod num;
-pub mod os;
-pub mod panic;
-pub mod path;
-pub mod process;
-pub mod sync;
-pub mod time;
-
-// Pull in `std_float` crate  into std. The contents of
-// `std_float` are in a different repository: rust-lang/portable-simd.
-#[path = "../../portable-simd/crates/std_float/src/lib.rs"]
-#[allow(missing_debug_implementations, dead_code, unsafe_op_in_unsafe_fn)]
-#[allow(rustdoc::bare_urls)]
-#[unstable(feature = "portable_simd", issue = "86656")]
-mod std_float;
-
-#[unstable(feature = "portable_simd", issue = "86656")]
-pub mod simd {
-    #![doc = include_str!("../../portable-simd/crates/core_simd/src/core_simd_docs.md")]
-
-    #[doc(inline)]
-    pub use crate::std_float::StdFloat;
-    #[doc(inline)]
-    pub use core::simd::*;
-}
-
-#[stable(feature = "futures_api", since = "1.36.0")]
-pub mod task {
-    //! Types and Traits for working with asynchronous tasks.
-
-    #[doc(inline)]
-    #[stable(feature = "futures_api", since = "1.36.0")]
-    pub use core::task::*;
-
-    #[doc(inline)]
-    #[stable(feature = "wake_trait", since = "1.51.0")]
-    pub use alloc::task::*;
-}
-
-#[doc = include_str!("../../stdarch/crates/core_arch/src/core_arch_docs.md")]
-#[stable(feature = "simd_arch", since = "1.27.0")]
-pub mod arch {
-    #[stable(feature = "simd_arch", since = "1.27.0")]
-    // The `no_inline`-attribute is required to make the documentation of all
-    // targets available.
-    // See https://github.com/rust-lang/rust/pull/57808#issuecomment-457390549 for
-    // more information.
-    #[doc(no_inline)] // Note (#82861): required for correct documentation
-    pub use core::arch::*;
-
-    #[stable(feature = "simd_aarch64", since = "1.60.0")]
-    pub use std_detect::is_aarch64_feature_detected;
-    #[unstable(feature = "stdarch_arm_feature_detection", issue = "111190")]
-    pub use std_detect::is_arm_feature_detected;
-    #[unstable(feature = "is_riscv_feature_detected", issue = "111192")]
-    pub use std_detect::is_riscv_feature_detected;
-    #[stable(feature = "simd_x86", since = "1.27.0")]
-    pub use std_detect::is_x86_feature_detected;
-    #[unstable(feature = "stdarch_mips_feature_detection", issue = "111188")]
-    pub use std_detect::{is_mips64_feature_detected, is_mips_feature_detected};
-    #[unstable(feature = "stdarch_powerpc_feature_detection", issue = "111191")]
-    pub use std_detect::{is_powerpc64_feature_detected, is_powerpc_feature_detected};
-}
-
-// This was stabilized in the crate root so we have to keep it there.
-#[stable(feature = "simd_x86", since = "1.27.0")]
-pub use std_detect::is_x86_feature_detected;
-
-// Platform-abstraction modules
-mod sys;
-mod sys_common;
 
-pub mod alloc;
-
-// Private support modules
-mod panicking;
-
-#[path = "../../backtrace/src/lib.rs"]
-#[allow(dead_code, unused_attributes, fuzzy_provenance_casts)]
-mod backtrace_rs;
-
-// Re-export macros defined in core.
-#[stable(feature = "rust1", since = "1.0.0")]
-#[allow(deprecated, deprecated_in_future)]
-pub use core::{
-    assert_eq, assert_ne, debug_assert, debug_assert_eq, debug_assert_ne, matches, todo, r#try,
-    unimplemented, unreachable, write, writeln,
-};
-
-// Re-export built-in macros defined through core.
-#[stable(feature = "builtin_macro_prelude", since = "1.38.0")]
-#[allow(deprecated)]
-pub use core::{
-    assert, assert_matches, cfg, column, compile_error, concat, concat_idents, const_format_args,
-    env, file, format_args, format_args_nl, include, include_bytes, include_str, line, log_syntax,
-    module_path, option_env, stringify, trace_macros,
-};
-
-#[unstable(
-    feature = "concat_bytes",
-    issue = "87555",
-    reason = "`concat_bytes` is not stable enough for use and is subject to change"
-)]
-pub use core::concat_bytes;
-
-#[unstable(feature = "cfg_match", issue = "115585")]
-pub use core::cfg_match;
-
-#[stable(feature = "core_primitive", since = "1.43.0")]
-pub use core::primitive;
-
-// Include a number of private modules that exist solely to provide
-// the rustdoc documentation for primitive types. Using `include!`
-// because rustdoc only looks for these modules at the crate level.
-include!("../../core/src/primitive_docs.rs");
-
-// Include a number of private modules that exist solely to provide
-// the rustdoc documentation for the existing keywords. Using `include!`
-// because rustdoc only looks for these modules at the crate level.
-include!("keyword_docs.rs");
-
-// This is required to avoid an unstable error when `restricted-std` is not
-// enabled. The use of #![feature(restricted_std)] in rustc-std-workspace-std
-// is unconditional, so the unstable feature needs to be defined somewhere.
-#[unstable(feature = "restricted_std", issue = "none")]
-mod __restricted_std_workaround {}
-
-mod sealed {
-    /// This trait being unreachable from outside the crate
-    /// prevents outside implementations of our extension traits.
-    /// This allows adding more trait methods in the future.
-    #[unstable(feature = "sealed", issue = "none")]
-    pub trait Sealed {}
-}
-
-#[cfg(test)]
-#[allow(dead_code)] // Not used in all configurations.
-pub(crate) mod test_helpers {
-    /// Test-only replacement for `rand::thread_rng()`, which is unusable for
-    /// us, as we want to allow running stdlib tests on tier-3 targets which may
-    /// not have `getrandom` support.
-    ///
-    /// Does a bit of a song and dance to ensure that the seed is different on
-    /// each call (as some tests sadly rely on this), but doesn't try that hard.
-    ///
-    /// This is duplicated in the `core`, `alloc` test suites (as well as
-    /// `std`'s integration tests), but figuring out a mechanism to share these
-    /// seems far more painful than copy-pasting a 7 line function a couple
-    /// times, given that even under a perma-unstable feature, I don't think we
-    /// want to expose types from `rand` from `std`.
-    #[track_caller]
-    pub(crate) fn test_rng() -> rand_xorshift::XorShiftRng {
-        use core::hash::{BuildHasher, Hash, Hasher};
-        let mut hasher = crate::hash::RandomState::new().build_hasher();
-        core::panic::Location::caller().hash(&mut hasher);
-        let hc64 = hasher.finish();
-        let seed_vec = hc64.to_le_bytes().into_iter().chain(0u8..8).collect::<Vec<u8>>();
-        let seed: [u8; 16] = seed_vec.as_slice().try_into().unwrap();
-        rand::SeedableRng::from_seed(seed)
-    }
-}
+#[cfg(not(all(feature = "miri-test", not(any(test, doctest)))))]
+include!("lib_.rs");