diff --git a/configure b/configure index 597f007633640..c751ad9731a7d 100755 --- a/configure +++ b/configure @@ -649,6 +649,7 @@ opt codegen-tests 1 "run the src/test/codegen tests" opt option-checking 1 "complain about unrecognized options in this configure script" opt ninja 0 "build LLVM using the Ninja generator (for MSVC, requires building in the correct environment)" opt vendor 0 "enable usage of vendored Rust crates" +opt sanitizers 0 "build the sanitizer runtimes (asan, lsan, msan, tsan)" # Optimization and debugging options. These may be overridden by the release channel, etc. opt_nosave optimize 1 "build optimized rust code" diff --git a/src/Cargo.lock b/src/Cargo.lock index 53721d48d9779..09aefd45e94c8 100644 --- a/src/Cargo.lock +++ b/src/Cargo.lock @@ -277,6 +277,16 @@ name = "rustc-serialize" version = "0.3.19" source = "registry+https://github.com/rust-lang/crates.io-index" +[[package]] +name = "rustc_asan" +version = "0.0.0" +dependencies = [ + "alloc_system 0.0.0", + "build_helper 0.1.0", + "cmake 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)", + "core 0.0.0", +] + [[package]] name = "rustc_back" version = "0.0.0" @@ -410,6 +420,16 @@ dependencies = [ "rustc_bitflags 0.0.0", ] +[[package]] +name = "rustc_lsan" +version = "0.0.0" +dependencies = [ + "alloc_system 0.0.0", + "build_helper 0.1.0", + "cmake 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)", + "core 0.0.0", +] + [[package]] name = "rustc_metadata" version = "0.0.0" @@ -444,6 +464,16 @@ dependencies = [ "syntax_pos 0.0.0", ] +[[package]] +name = "rustc_msan" +version = "0.0.0" +dependencies = [ + "alloc_system 0.0.0", + "build_helper 0.1.0", + "cmake 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)", + "core 0.0.0", +] + [[package]] name = "rustc_passes" version = "0.0.0" @@ -525,6 +555,16 @@ dependencies = [ "syntax_pos 0.0.0", ] +[[package]] +name = "rustc_tsan" +version = "0.0.0" +dependencies = [ + "alloc_system 0.0.0", + "build_helper 0.1.0", + "cmake 0.1.18 (registry+https://github.com/rust-lang/crates.io-index)", + "core 0.0.0", +] + [[package]] name = "rustc_typeck" version = "0.0.0" @@ -586,6 +626,10 @@ dependencies = [ "panic_abort 0.0.0", "panic_unwind 0.0.0", "rand 0.0.0", + "rustc_asan 0.0.0", + "rustc_lsan 0.0.0", + "rustc_msan 0.0.0", + "rustc_tsan 0.0.0", "std_unicode 0.0.0", "unwind 0.0.0", ] diff --git a/src/bootstrap/check.rs b/src/bootstrap/check.rs index 0ebd105513290..cbfbcbe4f0c6e 100644 --- a/src/bootstrap/check.rs +++ b/src/bootstrap/check.rs @@ -242,6 +242,10 @@ pub fn compiletest(build: &Build, cmd.env("RUSTC_BOOTSTRAP", "1"); build.add_rust_test_threads(&mut cmd); + if build.config.sanitizers { + cmd.env("SANITIZER_SUPPORT", "1"); + } + cmd.arg("--adb-path").arg("adb"); cmd.arg("--adb-test-dir").arg(ADB_TEST_DIR); if target.contains("android") { diff --git a/src/bootstrap/compile.rs b/src/bootstrap/compile.rs index 81dd42a1e906a..0b1a1f39d8d42 100644 --- a/src/bootstrap/compile.rs +++ b/src/bootstrap/compile.rs @@ -51,6 +51,17 @@ pub fn std(build: &Build, target: &str, compiler: &Compiler) { if compiler.stage == 0 && build.local_rebuild && !build.config.use_jemalloc { features.push_str(" force_alloc_system"); } + + if compiler.stage != 0 && build.config.sanitizers { + // This variable is used by the sanitizer runtime crates, e.g. + // rustc_lsan, to build the sanitizer runtime from C code + // When this variable is missing, those crates won't compile the C code, + // so we don't set this variable during stage0 where llvm-config is + // missing + // We also only build the runtimes when --enable-sanitizers (or its + // config.toml equivalent) is used + cargo.env("LLVM_CONFIG", build.llvm_config(target)); + } cargo.arg("--features").arg(features) .arg("--manifest-path") .arg(build.src.join("src/rustc/std_shim/Cargo.toml")); diff --git a/src/bootstrap/config.rs b/src/bootstrap/config.rs index 4e67a14345b9e..604c0397d5242 100644 --- a/src/bootstrap/config.rs +++ b/src/bootstrap/config.rs @@ -48,6 +48,7 @@ pub struct Config { pub target_config: HashMap, pub full_bootstrap: bool, pub extended: bool, + pub sanitizers: bool, // llvm codegen options pub llvm_assertions: bool, @@ -149,6 +150,7 @@ struct Build { python: Option, full_bootstrap: Option, extended: Option, + sanitizers: Option, } /// TOML representation of various global install decisions. @@ -294,6 +296,7 @@ impl Config { set(&mut config.vendor, build.vendor); set(&mut config.full_bootstrap, build.full_bootstrap); set(&mut config.extended, build.extended); + set(&mut config.sanitizers, build.sanitizers); if let Some(ref install) = toml.install { config.prefix = install.prefix.clone().map(PathBuf::from); @@ -438,6 +441,7 @@ impl Config { ("VENDOR", self.vendor), ("FULL_BOOTSTRAP", self.full_bootstrap), ("EXTENDED", self.extended), + ("SANITIZERS", self.sanitizers), } match key { diff --git a/src/bootstrap/config.toml.example b/src/bootstrap/config.toml.example index a53419ad7fd78..025fe990f91da 100644 --- a/src/bootstrap/config.toml.example +++ b/src/bootstrap/config.toml.example @@ -124,6 +124,9 @@ # disabled by default. #extended = false +# Build the sanitizer runtimes +#sanitizers = false + # ============================================================================= # General install configuration options # ============================================================================= diff --git a/src/bootstrap/lib.rs b/src/bootstrap/lib.rs index e58dcc9fce92f..ba6b34343f0b3 100644 --- a/src/bootstrap/lib.rs +++ b/src/bootstrap/lib.rs @@ -599,7 +599,8 @@ impl Build { /// Get the space-separated set of activated features for the standard /// library. fn std_features(&self) -> String { - let mut features = "panic-unwind".to_string(); + let mut features = "panic-unwind asan lsan msan tsan".to_string(); + if self.config.debug_jemalloc { features.push_str(" debug-jemalloc"); } diff --git a/src/ci/docker/dist-x86-linux/Dockerfile b/src/ci/docker/dist-x86-linux/Dockerfile index 4e4f5dd6f1e53..a06e47c3bc922 100644 --- a/src/ci/docker/dist-x86-linux/Dockerfile +++ b/src/ci/docker/dist-x86-linux/Dockerfile @@ -63,6 +63,11 @@ RUN ./build-git.sh COPY build-cmake.sh /tmp/ RUN ./build-cmake.sh +# for sanitizers, we need kernel headers files newer than the ones CentOS ships +# with so we install newer ones here +COPY build-headers.sh /tmp/ +RUN ./build-headers.sh + RUN curl -Lo /rustroot/dumb-init \ https://github.com/Yelp/dumb-init/releases/download/v1.2.0/dumb-init_1.2.0_amd64 && \ chmod +x /rustroot/dumb-init @@ -76,5 +81,5 @@ RUN curl -L https://api.pub.build.mozilla.org/tooltool/sha512/$SCCACHE_DIGEST | ENV HOSTS=i686-unknown-linux-gnu ENV HOSTS=$HOSTS,x86_64-unknown-linux-gnu -ENV RUST_CONFIGURE_ARGS --host=$HOSTS --enable-extended +ENV RUST_CONFIGURE_ARGS --host=$HOSTS --enable-extended --enable-sanitizers ENV SCRIPT python2.7 ../x.py dist --host $HOSTS --target $HOSTS diff --git a/src/ci/docker/dist-x86-linux/build-headers.sh b/src/ci/docker/dist-x86-linux/build-headers.sh new file mode 100755 index 0000000000000..4ce38fd9205e2 --- /dev/null +++ b/src/ci/docker/dist-x86-linux/build-headers.sh @@ -0,0 +1,25 @@ +#!/bin/bash +# Copyright 2017 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 or the MIT license +# , at your +# option. This file may not be copied, modified, or distributed +# except according to those terms. + +set -ex +source shared.sh + +curl https://cdn.kernel.org/pub/linux/kernel/v3.x/linux-3.2.84.tar.xz | unxz | tar x + +cd linux-3.2.84 +hide_output make mrproper +hide_output make INSTALL_HDR_PATH=dest headers_install + +find dest/include \( -name .install -o -name ..install.cmd \) -delete +yes | cp -fr dest/include/* /usr/include + +cd .. +rm -rf linux-3.2.84 diff --git a/src/ci/docker/x86_64-gnu/Dockerfile b/src/ci/docker/x86_64-gnu/Dockerfile index 6919487e17c3e..e903b6ddc64cd 100644 --- a/src/ci/docker/x86_64-gnu/Dockerfile +++ b/src/ci/docker/x86_64-gnu/Dockerfile @@ -22,5 +22,5 @@ RUN curl -OL https://github.com/Yelp/dumb-init/releases/download/v1.2.0/dumb-ini rm dumb-init_*.deb ENTRYPOINT ["/usr/bin/dumb-init", "--"] -ENV RUST_CONFIGURE_ARGS --build=x86_64-unknown-linux-gnu +ENV RUST_CONFIGURE_ARGS --build=x86_64-unknown-linux-gnu --enable-sanitizers ENV SCRIPT python2.7 ../x.py test && python2.7 ../x.py dist diff --git a/src/compiler-rt b/src/compiler-rt index a8fc4c169fac4..d30da544a8afc 160000 --- a/src/compiler-rt +++ b/src/compiler-rt @@ -1 +1 @@ -Subproject commit a8fc4c169fac43a5dc204d4fd56ddb1739f8c178 +Subproject commit d30da544a8afc5d78391dee270bdf40e74a215d3 diff --git a/src/librustc/middle/cstore.rs b/src/librustc/middle/cstore.rs index 6537cc1adce00..2d80fc32c469d 100644 --- a/src/librustc/middle/cstore.rs +++ b/src/librustc/middle/cstore.rs @@ -229,6 +229,7 @@ pub trait CrateStore<'tcx> { fn is_allocator(&self, cnum: CrateNum) -> bool; fn is_panic_runtime(&self, cnum: CrateNum) -> bool; fn is_compiler_builtins(&self, cnum: CrateNum) -> bool; + fn is_sanitizer_runtime(&self, cnum: CrateNum) -> bool; fn panic_strategy(&self, cnum: CrateNum) -> PanicStrategy; fn extern_crate(&self, cnum: CrateNum) -> Option; /// The name of the crate as it is referred to in source code of the current @@ -390,6 +391,7 @@ impl<'tcx> CrateStore<'tcx> for DummyCrateStore { fn is_allocator(&self, cnum: CrateNum) -> bool { bug!("is_allocator") } fn is_panic_runtime(&self, cnum: CrateNum) -> bool { bug!("is_panic_runtime") } fn is_compiler_builtins(&self, cnum: CrateNum) -> bool { bug!("is_compiler_builtins") } + fn is_sanitizer_runtime(&self, cnum: CrateNum) -> bool { bug!("is_sanitizer_runtime") } fn panic_strategy(&self, cnum: CrateNum) -> PanicStrategy { bug!("panic_strategy") } diff --git a/src/librustc/session/config.rs b/src/librustc/session/config.rs index d41c2ba93b935..24615f2fa6992 100644 --- a/src/librustc/session/config.rs +++ b/src/librustc/session/config.rs @@ -51,6 +51,14 @@ pub struct Config { pub uint_type: UintTy, } +#[derive(Clone)] +pub enum Sanitizer { + Address, + Leak, + Memory, + Thread, +} + #[derive(Clone, Copy, PartialEq, Hash)] pub enum OptLevel { No, // -O0 @@ -626,11 +634,13 @@ macro_rules! options { Some("a number"); pub const parse_panic_strategy: Option<&'static str> = Some("either `panic` or `abort`"); + pub const parse_sanitizer: Option<&'static str> = + Some("one of: `address`, `leak`, `memory` or `thread`"); } #[allow(dead_code)] mod $mod_set { - use super::{$struct_name, Passes, SomePasses, AllPasses}; + use super::{$struct_name, Passes, SomePasses, AllPasses, Sanitizer}; use rustc_back::PanicStrategy; $( @@ -751,6 +761,17 @@ macro_rules! options { } true } + + fn parse_sanitizer(slote: &mut Option, v: Option<&str>) -> bool { + match v { + Some("address") => *slote = Some(Sanitizer::Address), + Some("leak") => *slote = Some(Sanitizer::Leak), + Some("memory") => *slote = Some(Sanitizer::Memory), + Some("thread") => *slote = Some(Sanitizer::Thread), + _ => return false, + } + true + } } ) } @@ -949,6 +970,8 @@ options! {DebuggingOptions, DebuggingSetter, basic_debugging_options, "encode MIR of all functions into the crate metadata"), osx_rpath_install_name: bool = (false, parse_bool, [TRACKED], "pass `-install_name @rpath/...` to the OSX linker"), + sanitizer: Option = (None, parse_sanitizer, [UNTRACKED], + "Use a sanitizer"), } pub fn default_lib_output() -> CrateType { diff --git a/src/librustc_asan/Cargo.toml b/src/librustc_asan/Cargo.toml new file mode 100644 index 0000000000000..2d4872b1fc942 --- /dev/null +++ b/src/librustc_asan/Cargo.toml @@ -0,0 +1,17 @@ +[package] +authors = ["The Rust Project Developers"] +build = "build.rs" +name = "rustc_asan" +version = "0.0.0" + +[lib] +name = "rustc_asan" +path = "lib.rs" + +[build-dependencies] +build_helper = { path = "../build_helper" } +cmake = "0.1.18" + +[dependencies] +alloc_system = { path = "../liballoc_system" } +core = { path = "../libcore" } diff --git a/src/librustc_asan/build.rs b/src/librustc_asan/build.rs new file mode 100644 index 0000000000000..015be14bd495a --- /dev/null +++ b/src/librustc_asan/build.rs @@ -0,0 +1,39 @@ +// Copyright 2016 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +extern crate build_helper; +extern crate cmake; + +use std::path::PathBuf; +use std::env; + +use cmake::Config; + +fn main() { + if let Some(llvm_config) = env::var_os("LLVM_CONFIG") { + let dst = Config::new("../compiler-rt") + .define("COMPILER_RT_BUILD_SANITIZERS", "ON") + .define("COMPILER_RT_BUILD_BUILTINS", "OFF") + .define("COMPILER_RT_BUILD_XRAY", "OFF") + .define("LLVM_CONFIG_PATH", llvm_config) + .build_target("asan") + .build(); + + println!("cargo:rustc-link-search=native={}", + dst.join("build/lib/linux").display()); + println!("cargo:rustc-link-lib=static=clang_rt.asan-x86_64"); + + build_helper::rerun_if_changed_anything_in_dir(&PathBuf::from(env::var("CARGO_MANIFEST_DIR") + .unwrap()) + .join("../compiler-rt")); + } + + println!("cargo:rerun-if-changed=build.rs"); +} diff --git a/src/librustc_asan/lib.rs b/src/librustc_asan/lib.rs new file mode 100644 index 0000000000000..71a166b91ebcb --- /dev/null +++ b/src/librustc_asan/lib.rs @@ -0,0 +1,20 @@ +// Copyright 2016 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![cfg_attr(not(stage0), feature(sanitizer_runtime))] +#![cfg_attr(not(stage0), sanitizer_runtime)] +#![feature(alloc_system)] +#![feature(staged_api)] +#![no_std] +#![unstable(feature = "sanitizer_runtime_lib", + reason = "internal implementation detail of sanitizers", + issue = "0")] + +extern crate alloc_system; diff --git a/src/librustc_llvm/ffi.rs b/src/librustc_llvm/ffi.rs index 07d36448ab0f8..949e949f673a2 100644 --- a/src/librustc_llvm/ffi.rs +++ b/src/librustc_llvm/ffi.rs @@ -126,6 +126,9 @@ pub enum Attribute { UWTable = 17, ZExt = 18, InReg = 19, + SanitizeThread = 20, + SanitizeAddress = 21, + SanitizeMemory = 22, } /// LLVMIntPredicate diff --git a/src/librustc_lsan/Cargo.toml b/src/librustc_lsan/Cargo.toml new file mode 100644 index 0000000000000..bc1f2ead76884 --- /dev/null +++ b/src/librustc_lsan/Cargo.toml @@ -0,0 +1,17 @@ +[package] +authors = ["The Rust Project Developers"] +build = "build.rs" +name = "rustc_lsan" +version = "0.0.0" + +[lib] +name = "rustc_lsan" +path = "lib.rs" + +[build-dependencies] +build_helper = { path = "../build_helper" } +cmake = "0.1.18" + +[dependencies] +alloc_system = { path = "../liballoc_system" } +core = { path = "../libcore" } diff --git a/src/librustc_lsan/build.rs b/src/librustc_lsan/build.rs new file mode 100644 index 0000000000000..5773777d1f81b --- /dev/null +++ b/src/librustc_lsan/build.rs @@ -0,0 +1,39 @@ +// Copyright 2016 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +extern crate build_helper; +extern crate cmake; + +use std::path::PathBuf; +use std::env; + +use cmake::Config; + +fn main() { + if let Some(llvm_config) = env::var_os("LLVM_CONFIG") { + let dst = Config::new("../compiler-rt") + .define("COMPILER_RT_BUILD_SANITIZERS", "ON") + .define("COMPILER_RT_BUILD_BUILTINS", "OFF") + .define("COMPILER_RT_BUILD_XRAY", "OFF") + .define("LLVM_CONFIG_PATH", llvm_config) + .build_target("lsan") + .build(); + + println!("cargo:rustc-link-search=native={}", + dst.join("build/lib/linux").display()); + println!("cargo:rustc-link-lib=static=clang_rt.lsan-x86_64"); + + build_helper::rerun_if_changed_anything_in_dir(&PathBuf::from(env::var("CARGO_MANIFEST_DIR") + .unwrap()) + .join("../compiler-rt")); + } + + println!("cargo:rerun-if-changed=build.rs"); +} diff --git a/src/librustc_lsan/lib.rs b/src/librustc_lsan/lib.rs new file mode 100644 index 0000000000000..71a166b91ebcb --- /dev/null +++ b/src/librustc_lsan/lib.rs @@ -0,0 +1,20 @@ +// Copyright 2016 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![cfg_attr(not(stage0), feature(sanitizer_runtime))] +#![cfg_attr(not(stage0), sanitizer_runtime)] +#![feature(alloc_system)] +#![feature(staged_api)] +#![no_std] +#![unstable(feature = "sanitizer_runtime_lib", + reason = "internal implementation detail of sanitizers", + issue = "0")] + +extern crate alloc_system; diff --git a/src/librustc_metadata/creader.rs b/src/librustc_metadata/creader.rs index 81a4f7c93b6e9..55dc5aa2876f6 100644 --- a/src/librustc_metadata/creader.rs +++ b/src/librustc_metadata/creader.rs @@ -17,7 +17,8 @@ use schema::CrateRoot; use rustc::hir::def_id::{CrateNum, DefIndex}; use rustc::hir::svh::Svh; use rustc::middle::cstore::DepKind; -use rustc::session::{config, Session}; +use rustc::session::Session; +use rustc::session::config::{Sanitizer, self}; use rustc_back::PanicStrategy; use rustc::session::search_paths::PathKind; use rustc::middle; @@ -786,6 +787,64 @@ impl<'a> CrateLoader<'a> { &|data| data.needs_panic_runtime()); } + fn inject_sanitizer_runtime(&mut self) { + if let Some(ref sanitizer) = self.sess.opts.debugging_opts.sanitizer { + // Sanitizers can only be used with x86_64 Linux executables linked + // to `std` + if self.sess.target.target.llvm_target != "x86_64-unknown-linux-gnu" { + self.sess.err(&format!("Sanitizers only work with the \ + `x86_64-unknown-linux-gnu` target.")); + return + } + + if !self.sess.crate_types.borrow().iter().all(|ct| { + match *ct { + // Link the runtime + config::CrateTypeExecutable => true, + // This crate will be compiled with the required + // instrumentation pass + config::CrateTypeRlib => false, + _ => { + self.sess.err(&format!("Only executables and rlibs can be \ + compiled with `-Z sanitizer`")); + false + } + } + }) { + return + } + + let mut uses_std = false; + self.cstore.iter_crate_data(|_, data| { + if data.name == "std" { + uses_std = true; + } + }); + + if uses_std { + let name = match *sanitizer { + Sanitizer::Address => "rustc_asan", + Sanitizer::Leak => "rustc_lsan", + Sanitizer::Memory => "rustc_msan", + Sanitizer::Thread => "rustc_tsan", + }; + info!("loading sanitizer: {}", name); + + let symbol = Symbol::intern(name); + let dep_kind = DepKind::Implicit; + let (_, data) = + self.resolve_crate(&None, symbol, symbol, None, DUMMY_SP, + PathKind::Crate, dep_kind); + + // Sanity check the loaded crate to ensure it is indeed a sanitizer runtime + if !data.is_sanitizer_runtime() { + self.sess.err(&format!("the crate `{}` is not a sanitizer runtime", + name)); + } + } + } + } + fn inject_allocator_crate(&mut self) { // Make sure that we actually need an allocator, if none of our // dependencies need one then we definitely don't! @@ -982,6 +1041,9 @@ impl<'a> CrateLoader<'a> { impl<'a> middle::cstore::CrateLoader for CrateLoader<'a> { fn postprocess(&mut self, krate: &ast::Crate) { + // inject the sanitizer runtime before the allocator runtime because all + // sanitizers force the use of the `alloc_system` allocator + self.inject_sanitizer_runtime(); self.inject_allocator_crate(); self.inject_panic_runtime(krate); diff --git a/src/librustc_metadata/cstore.rs b/src/librustc_metadata/cstore.rs index beba5faf3d034..4709ca6101c79 100644 --- a/src/librustc_metadata/cstore.rs +++ b/src/librustc_metadata/cstore.rs @@ -297,6 +297,11 @@ impl CrateMetadata { attr::contains_name(&attrs, "compiler_builtins") } + pub fn is_sanitizer_runtime(&self) -> bool { + let attrs = self.get_item_attrs(CRATE_DEF_INDEX); + attr::contains_name(&attrs, "sanitizer_runtime") + } + pub fn is_no_builtins(&self) -> bool { let attrs = self.get_item_attrs(CRATE_DEF_INDEX); attr::contains_name(&attrs, "no_builtins") diff --git a/src/librustc_metadata/cstore_impl.rs b/src/librustc_metadata/cstore_impl.rs index 39581a4696088..7b0177bfd23ed 100644 --- a/src/librustc_metadata/cstore_impl.rs +++ b/src/librustc_metadata/cstore_impl.rs @@ -297,6 +297,10 @@ impl<'tcx> CrateStore<'tcx> for cstore::CStore { self.get_crate_data(cnum).is_compiler_builtins() } + fn is_sanitizer_runtime(&self, cnum: CrateNum) -> bool { + self.get_crate_data(cnum).is_sanitizer_runtime() + } + fn panic_strategy(&self, cnum: CrateNum) -> PanicStrategy { self.get_crate_data(cnum).panic_strategy() } diff --git a/src/librustc_msan/Cargo.toml b/src/librustc_msan/Cargo.toml new file mode 100644 index 0000000000000..45cc6b9839fb8 --- /dev/null +++ b/src/librustc_msan/Cargo.toml @@ -0,0 +1,17 @@ +[package] +authors = ["The Rust Project Developers"] +build = "build.rs" +name = "rustc_msan" +version = "0.0.0" + +[lib] +name = "rustc_msan" +path = "lib.rs" + +[build-dependencies] +build_helper = { path = "../build_helper" } +cmake = "0.1.18" + +[dependencies] +alloc_system = { path = "../liballoc_system" } +core = { path = "../libcore" } diff --git a/src/librustc_msan/build.rs b/src/librustc_msan/build.rs new file mode 100644 index 0000000000000..7a4c8f7073933 --- /dev/null +++ b/src/librustc_msan/build.rs @@ -0,0 +1,39 @@ +// Copyright 2016 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +extern crate build_helper; +extern crate cmake; + +use std::path::PathBuf; +use std::env; + +use cmake::Config; + +fn main() { + if let Some(llvm_config) = env::var_os("LLVM_CONFIG") { + let dst = Config::new("../compiler-rt") + .define("COMPILER_RT_BUILD_SANITIZERS", "ON") + .define("COMPILER_RT_BUILD_BUILTINS", "OFF") + .define("COMPILER_RT_BUILD_XRAY", "OFF") + .define("LLVM_CONFIG_PATH", llvm_config) + .build_target("msan") + .build(); + + println!("cargo:rustc-link-search=native={}", + dst.join("build/lib/linux").display()); + println!("cargo:rustc-link-lib=static=clang_rt.msan-x86_64"); + + build_helper::rerun_if_changed_anything_in_dir(&PathBuf::from(env::var("CARGO_MANIFEST_DIR") + .unwrap()) + .join("../compiler-rt")); + } + + println!("cargo:rerun-if-changed=build.rs"); +} diff --git a/src/librustc_msan/lib.rs b/src/librustc_msan/lib.rs new file mode 100644 index 0000000000000..71a166b91ebcb --- /dev/null +++ b/src/librustc_msan/lib.rs @@ -0,0 +1,20 @@ +// Copyright 2016 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![cfg_attr(not(stage0), feature(sanitizer_runtime))] +#![cfg_attr(not(stage0), sanitizer_runtime)] +#![feature(alloc_system)] +#![feature(staged_api)] +#![no_std] +#![unstable(feature = "sanitizer_runtime_lib", + reason = "internal implementation detail of sanitizers", + issue = "0")] + +extern crate alloc_system; diff --git a/src/librustc_trans/back/link.rs b/src/librustc_trans/back/link.rs index 4ddf8a883bc48..1cbfa26b705ac 100644 --- a/src/librustc_trans/back/link.rs +++ b/src/librustc_trans/back/link.rs @@ -1031,6 +1031,9 @@ fn add_upstream_rust_crates(cmd: &mut Linker, // symbols from the dylib. let src = sess.cstore.used_crate_source(cnum); match data[cnum.as_usize() - 1] { + _ if sess.cstore.is_sanitizer_runtime(cnum) => { + link_sanitizer_runtime(cmd, sess, tmpdir, cnum); + } // compiler-builtins are always placed last to ensure that they're // linked correctly. _ if sess.cstore.is_compiler_builtins(cnum) => { @@ -1048,6 +1051,8 @@ fn add_upstream_rust_crates(cmd: &mut Linker, } } + // compiler-builtins are always placed last to ensure that they're + // linked correctly. // We must always link the `compiler_builtins` crate statically. Even if it // was already "included" in a dylib (e.g. `libstd` when `-C prefer-dynamic` // is used) @@ -1064,6 +1069,34 @@ fn add_upstream_rust_crates(cmd: &mut Linker, } } + // We must link the sanitizer runtime using -Wl,--whole-archive but since + // it's packed in a .rlib, it contains stuff that are not objects that will + // make the linker error. So we must remove those bits from the .rlib before + // linking it. + fn link_sanitizer_runtime(cmd: &mut Linker, + sess: &Session, + tmpdir: &Path, + cnum: CrateNum) { + let src = sess.cstore.used_crate_source(cnum); + let cratepath = &src.rlib.unwrap().0; + let dst = tmpdir.join(cratepath.file_name().unwrap()); + let cfg = archive_config(sess, &dst, Some(cratepath)); + let mut archive = ArchiveBuilder::new(cfg); + archive.update_symbols(); + + for f in archive.src_files() { + if f.ends_with("bytecode.deflate") || + f == sess.cstore.metadata_filename() { + archive.remove_file(&f); + continue + } + } + + archive.build(); + + cmd.link_whole_rlib(&dst); + } + // Adds the static "rlib" versions of all crates to the command line. // There's a bit of magic which happens here specifically related to LTO and // dynamic libraries. Specifically: diff --git a/src/librustc_trans/back/write.rs b/src/librustc_trans/back/write.rs index 9a761e17e75e8..5c4a5a9a4423d 100644 --- a/src/librustc_trans/back/write.rs +++ b/src/librustc_trans/back/write.rs @@ -12,7 +12,7 @@ use back::lto; use back::link::{get_linker, remove}; use back::symbol_export::ExportedSymbols; use rustc_incremental::{save_trans_partition, in_incr_comp_dir}; -use session::config::{OutputFilenames, OutputTypes, Passes, SomePasses, AllPasses}; +use session::config::{OutputFilenames, OutputTypes, Passes, SomePasses, AllPasses, Sanitizer}; use session::Session; use session::config::{self, OutputType}; use llvm; @@ -679,6 +679,22 @@ pub fn run_passes(sess: &Session, let mut modules_config = ModuleConfig::new(tm, sess.opts.cg.passes.clone()); let mut metadata_config = ModuleConfig::new(tm, vec![]); + if let Some(ref sanitizer) = sess.opts.debugging_opts.sanitizer { + match *sanitizer { + Sanitizer::Address => { + modules_config.passes.push("asan".to_owned()); + modules_config.passes.push("asan-module".to_owned()); + } + Sanitizer::Memory => { + modules_config.passes.push("msan".to_owned()) + } + Sanitizer::Thread => { + modules_config.passes.push("tsan".to_owned()) + } + _ => {} + } + } + modules_config.opt_level = Some(get_llvm_opt_level(sess.opts.optimize)); modules_config.opt_size = Some(get_llvm_opt_size(sess.opts.optimize)); diff --git a/src/librustc_trans/declare.rs b/src/librustc_trans/declare.rs index bf7a02eb0f196..7ac482459ee39 100644 --- a/src/librustc_trans/declare.rs +++ b/src/librustc_trans/declare.rs @@ -23,6 +23,7 @@ use llvm::{self, ValueRef}; use llvm::AttributePlace::Function; use rustc::ty; +use rustc::session::config::Sanitizer; use abi::{Abi, FnType}; use attributes; use context::CrateContext; @@ -72,6 +73,21 @@ fn declare_raw_fn(ccx: &CrateContext, name: &str, callconv: llvm::CallConv, ty: llvm::Attribute::NoRedZone.apply_llfn(Function, llfn); } + if let Some(ref sanitizer) = ccx.tcx().sess.opts.debugging_opts.sanitizer { + match *sanitizer { + Sanitizer::Address => { + llvm::Attribute::SanitizeAddress.apply_llfn(Function, llfn); + }, + Sanitizer::Memory => { + llvm::Attribute::SanitizeMemory.apply_llfn(Function, llfn); + }, + Sanitizer::Thread => { + llvm::Attribute::SanitizeThread.apply_llfn(Function, llfn); + }, + _ => {} + } + } + // If we're compiling the compiler-builtins crate, e.g. the equivalent of // compiler-rt, then we want to implicitly compile everything with hidden // visibility as we're going to link this object all over the place but diff --git a/src/librustc_tsan/Cargo.toml b/src/librustc_tsan/Cargo.toml new file mode 100644 index 0000000000000..66d6236361ea2 --- /dev/null +++ b/src/librustc_tsan/Cargo.toml @@ -0,0 +1,17 @@ +[package] +authors = ["The Rust Project Developers"] +build = "build.rs" +name = "rustc_tsan" +version = "0.0.0" + +[lib] +name = "rustc_tsan" +path = "lib.rs" + +[build-dependencies] +build_helper = { path = "../build_helper" } +cmake = "0.1.18" + +[dependencies] +alloc_system = { path = "../liballoc_system" } +core = { path = "../libcore" } diff --git a/src/librustc_tsan/build.rs b/src/librustc_tsan/build.rs new file mode 100644 index 0000000000000..84326ae8a7106 --- /dev/null +++ b/src/librustc_tsan/build.rs @@ -0,0 +1,39 @@ +// Copyright 2016 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +extern crate build_helper; +extern crate cmake; + +use std::path::PathBuf; +use std::env; + +use cmake::Config; + +fn main() { + if let Some(llvm_config) = env::var_os("LLVM_CONFIG") { + let dst = Config::new("../compiler-rt") + .define("COMPILER_RT_BUILD_SANITIZERS", "ON") + .define("COMPILER_RT_BUILD_BUILTINS", "OFF") + .define("COMPILER_RT_BUILD_XRAY", "OFF") + .define("LLVM_CONFIG_PATH", llvm_config) + .build_target("tsan") + .build(); + + println!("cargo:rustc-link-search=native={}", + dst.join("build/lib/linux").display()); + println!("cargo:rustc-link-lib=static=clang_rt.tsan-x86_64"); + + build_helper::rerun_if_changed_anything_in_dir(&PathBuf::from(env::var("CARGO_MANIFEST_DIR") + .unwrap()) + .join("../compiler-rt")); + } + + println!("cargo:rerun-if-changed=build.rs"); +} diff --git a/src/librustc_tsan/lib.rs b/src/librustc_tsan/lib.rs new file mode 100644 index 0000000000000..71a166b91ebcb --- /dev/null +++ b/src/librustc_tsan/lib.rs @@ -0,0 +1,20 @@ +// Copyright 2016 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![cfg_attr(not(stage0), feature(sanitizer_runtime))] +#![cfg_attr(not(stage0), sanitizer_runtime)] +#![feature(alloc_system)] +#![feature(staged_api)] +#![no_std] +#![unstable(feature = "sanitizer_runtime_lib", + reason = "internal implementation detail of sanitizers", + issue = "0")] + +extern crate alloc_system; diff --git a/src/libstd/Cargo.toml b/src/libstd/Cargo.toml index 8146e7fb1edaf..2ba7517d3d202 100644 --- a/src/libstd/Cargo.toml +++ b/src/libstd/Cargo.toml @@ -23,13 +23,23 @@ compiler_builtins = { path = "../libcompiler_builtins" } std_unicode = { path = "../libstd_unicode" } unwind = { path = "../libunwind" } +[target.x86_64-unknown-linux-gnu.dependencies] +rustc_asan = { path = "../librustc_asan", optional = true } +rustc_lsan = { path = "../librustc_lsan", optional = true } +rustc_msan = { path = "../librustc_msan", optional = true } +rustc_tsan = { path = "../librustc_tsan", optional = true } + [build-dependencies] build_helper = { path = "../build_helper" } gcc = "0.3.27" [features] +asan = ["rustc_asan"] backtrace = [] debug-jemalloc = ["alloc_jemalloc/debug"] jemalloc = ["alloc_jemalloc"] force_alloc_system = [] +lsan = ["rustc_lsan"] +msan = ["rustc_msan"] panic-unwind = ["panic_unwind"] +tsan = ["rustc_tsan"] diff --git a/src/libsyntax/feature_gate.rs b/src/libsyntax/feature_gate.rs index a78c192a120df..cc0a67b3d2e94 100644 --- a/src/libsyntax/feature_gate.rs +++ b/src/libsyntax/feature_gate.rs @@ -328,6 +328,10 @@ declare_features! ( // `extern "msp430-interrupt" fn()` (active, abi_msp430_interrupt, "1.16.0", Some(38487)), + + // Used to identify crates that contain sanitizer runtimes + // rustc internal + (active, sanitizer_runtime, "1.17.0", None), ); declare_features! ( @@ -647,6 +651,12 @@ pub const BUILTIN_ATTRIBUTES: &'static [(&'static str, AttributeType, AttributeG contains compiler-rt intrinsics and will never be \ stable", cfg_fn!(compiler_builtins))), + ("sanitizer_runtime", Whitelisted, Gated(Stability::Unstable, + "sanitizer_runtime", + "the `#[sanitizer_runtime]` attribute is used to \ + identify crates that contain the runtime of a \ + sanitizer and will never be stable", + cfg_fn!(sanitizer_runtime))), ("allow_internal_unstable", Normal, Gated(Stability::Unstable, "allow_internal_unstable", diff --git a/src/rustc/std_shim/Cargo.toml b/src/rustc/std_shim/Cargo.toml index 14c9c5544b188..db96079d3e916 100644 --- a/src/rustc/std_shim/Cargo.toml +++ b/src/rustc/std_shim/Cargo.toml @@ -35,8 +35,12 @@ core = { path = "../../libcore" } # Reexport features from std [features] +asan = ["std/asan"] backtrace = ["std/backtrace"] debug-jemalloc = ["std/debug-jemalloc"] jemalloc = ["std/jemalloc"] force_alloc_system = ["std/force_alloc_system"] +lsan = ["std/lsan"] +msan = ["std/msan"] panic-unwind = ["std/panic-unwind"] +tsan = ["std/tsan"] diff --git a/src/rustllvm/RustWrapper.cpp b/src/rustllvm/RustWrapper.cpp index 4e201c254e39f..f3b52b71b99c1 100644 --- a/src/rustllvm/RustWrapper.cpp +++ b/src/rustllvm/RustWrapper.cpp @@ -148,6 +148,12 @@ static Attribute::AttrKind fromRust(LLVMRustAttribute Kind) { return Attribute::ZExt; case InReg: return Attribute::InReg; + case SanitizeThread: + return Attribute::SanitizeThread; + case SanitizeAddress: + return Attribute::SanitizeAddress; + case SanitizeMemory: + return Attribute::SanitizeMemory; } llvm_unreachable("bad AttributeKind"); } diff --git a/src/rustllvm/rustllvm.h b/src/rustllvm/rustllvm.h index a30fa3133e282..0baf5528e9356 100644 --- a/src/rustllvm/rustllvm.h +++ b/src/rustllvm/rustllvm.h @@ -98,6 +98,9 @@ enum LLVMRustAttribute { UWTable = 17, ZExt = 18, InReg = 19, + SanitizeThread = 20, + SanitizeAddress = 21, + SanitizeMemory = 22, }; typedef struct OpaqueRustString *RustStringRef; diff --git a/src/test/compile-fail/feature-gate-sanitizer-runtime.rs b/src/test/compile-fail/feature-gate-sanitizer-runtime.rs new file mode 100644 index 0000000000000..a18641d824691 --- /dev/null +++ b/src/test/compile-fail/feature-gate-sanitizer-runtime.rs @@ -0,0 +1,13 @@ +// Copyright 2016 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![sanitizer_runtime] //~ ERROR the `#[sanitizer_runtime]` attribute is + +fn main() {} diff --git a/src/test/run-make/sanitizer-address/Makefile b/src/test/run-make/sanitizer-address/Makefile new file mode 100644 index 0000000000000..5931145f3a47d --- /dev/null +++ b/src/test/run-make/sanitizer-address/Makefile @@ -0,0 +1,11 @@ +-include ../tools.mk + +# NOTE the address sanitizer only supports x86_64 linux +ifdef SANITIZER_SUPPORT +all: + $(RUSTC) -g -Z sanitizer=address -Z print-link-args overflow.rs | grep -q librustc_asan + $(TMPDIR)/overflow 2>&1 | grep -q stack-buffer-overflow +else +all: + +endif diff --git a/src/test/run-make/sanitizer-address/overflow.rs b/src/test/run-make/sanitizer-address/overflow.rs new file mode 100644 index 0000000000000..e35c3873f7eb5 --- /dev/null +++ b/src/test/run-make/sanitizer-address/overflow.rs @@ -0,0 +1,14 @@ +// Copyright 2017 The Rust Project Developers. See the COPYRIGHT +// file at the top-level directory of this distribution and at +// http://rust-lang.org/COPYRIGHT. +// +// Licensed under the Apache License, Version 2.0 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +fn main() { + let xs = [0, 1, 2, 3]; + let y = unsafe { *xs.as_ptr().offset(4) }; +} diff --git a/src/test/run-make/sanitizer-dylib/Makefile b/src/test/run-make/sanitizer-dylib/Makefile new file mode 100644 index 0000000000000..835d5b0d9d8cd --- /dev/null +++ b/src/test/run-make/sanitizer-dylib/Makefile @@ -0,0 +1,8 @@ +-include ../tools.mk + +ifeq ($(TARGET),x86_64-unknown-linux-gnu) +all: + $(RUSTC) -Z sanitizer=leak --crate-type dylib --target $(TARGET) hello.rs 2>&1 | grep -q 'Only executables and rlibs can be compiled with `-Z sanitizer`' +else +all: +endif diff --git a/src/test/run-make/sanitizer-dylib/hello.rs b/src/test/run-make/sanitizer-dylib/hello.rs new file mode 100644 index 0000000000000..41782851a1a6d --- /dev/null +++ b/src/test/run-make/sanitizer-dylib/hello.rs @@ -0,0 +1,13 @@ +// Copyright 2017 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +fn main() { + println!("Hello, world!"); +} diff --git a/src/test/run-make/sanitizer-invalid-target/Makefile b/src/test/run-make/sanitizer-invalid-target/Makefile new file mode 100644 index 0000000000000..6a1ce8bab2fb6 --- /dev/null +++ b/src/test/run-make/sanitizer-invalid-target/Makefile @@ -0,0 +1,4 @@ +-include ../tools.mk + +all: + $(RUSTC) -Z sanitizer=leak --target i686-unknown-linux-gnu hello.rs 2>&1 | grep -q 'Sanitizers only work with the `x86_64-unknown-linux-gnu` target' diff --git a/src/test/run-make/sanitizer-invalid-target/hello.rs b/src/test/run-make/sanitizer-invalid-target/hello.rs new file mode 100644 index 0000000000000..e9e46b7702a80 --- /dev/null +++ b/src/test/run-make/sanitizer-invalid-target/hello.rs @@ -0,0 +1,13 @@ +// Copyright 2017 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +#![feature(no_core)] +#![no_core] +#![no_main] diff --git a/src/test/run-make/sanitizer-leak/Makefile b/src/test/run-make/sanitizer-leak/Makefile new file mode 100644 index 0000000000000..f02d948fdc84f --- /dev/null +++ b/src/test/run-make/sanitizer-leak/Makefile @@ -0,0 +1,10 @@ +-include ../tools.mk + +ifdef SANITIZER_SUPPORT +all: + $(RUSTC) -C opt-level=1 -g -Z sanitizer=leak -Z print-link-args leak.rs | grep -q librustc_lsan + $(TMPDIR)/leak 2>&1 | grep -q 'detected memory leaks' +else +all: + +endif diff --git a/src/test/run-make/sanitizer-leak/leak.rs b/src/test/run-make/sanitizer-leak/leak.rs new file mode 100644 index 0000000000000..279da6aaae707 --- /dev/null +++ b/src/test/run-make/sanitizer-leak/leak.rs @@ -0,0 +1,16 @@ +// Copyright 2017 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +use std::mem; + +fn main() { + let xs = vec![1, 2, 3, 4]; + mem::forget(xs); +} diff --git a/src/test/run-make/sanitizer-memory/Makefile b/src/test/run-make/sanitizer-memory/Makefile new file mode 100644 index 0000000000000..08682e5975e51 --- /dev/null +++ b/src/test/run-make/sanitizer-memory/Makefile @@ -0,0 +1,10 @@ +-include ../tools.mk + +ifdef SANITIZER_SUPPORT +all: + $(RUSTC) -g -Z sanitizer=memory -Z print-link-args uninit.rs | grep -q librustc_msan + $(TMPDIR)/uninit 2>&1 | grep -q use-of-uninitialized-value +else +all: + +endif diff --git a/src/test/run-make/sanitizer-memory/uninit.rs b/src/test/run-make/sanitizer-memory/uninit.rs new file mode 100644 index 0000000000000..8350c7de3acab --- /dev/null +++ b/src/test/run-make/sanitizer-memory/uninit.rs @@ -0,0 +1,16 @@ +// Copyright 2017 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +use std::mem; + +fn main() { + let xs: [u8; 4] = unsafe { mem::uninitialized() }; + let y = xs[0] + xs[1]; +} diff --git a/src/test/run-make/sanitizer-thread/Makefile b/src/test/run-make/sanitizer-thread/Makefile new file mode 100644 index 0000000000000..8bb89a241cb05 --- /dev/null +++ b/src/test/run-make/sanitizer-thread/Makefile @@ -0,0 +1,10 @@ +-include ../tools.mk + +ifdef SANITIZER_SUPPORT +all: + $(RUSTC) -g -Z sanitizer=thread -Z print-link-args racy.rs | grep -q librustc_tsan + $(TMPDIR)/racy 2>&1 | grep -q 'data race' +else +all: + +endif diff --git a/src/test/run-make/sanitizer-thread/racy.rs b/src/test/run-make/sanitizer-thread/racy.rs new file mode 100644 index 0000000000000..dc929e004a479 --- /dev/null +++ b/src/test/run-make/sanitizer-thread/racy.rs @@ -0,0 +1,21 @@ +// Copyright 2017 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 or the MIT license +// , at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +use std::thread; + +static mut ANSWER: i32 = 0; + +fn main() { + let t1 = thread::spawn(|| unsafe { ANSWER = 42 }); + unsafe { + ANSWER = 24; + } + t1.join().ok(); +}