x86_64-pc-windows-gnu can't link libtest with LTO=thin

[ehuss]

x86_64-pc-windows-gnu is unable to build a test binary with LTO=thin.

Reproduction:

1. touch foo.rs
2. rustc +nightly-x86_64-pc-windows-gnu -Clto=thin --test foo.rs

Error:

error: linking with `x86_64-w64-mingw32-gcc` failed: exit code: 1
  |
  = note: "x86_64-w64-mingw32-gcc" "-fno-use-linker-plugin" "-Wl,--dynamicbase" "-Wl,--disable-auto-image-base" "-m64" "-Wl,--high-entropy-va" "C:\\Users\\User\\.rustup\\toolchains\\nightly-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\self-contained\\crt2.o" "C:\\Users\\User\\.rustup\\toolchains\\nightly-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\rsbegin.o" "C:\\Users\\User\\AppData\\Local\\Temp\\rustcSapTY6\\symbols.o" "foo.58ka7t7dknl8118b.rcgu.o" "foo.addr2line-14c0744e763fbcc5.addr2line.a755ea22-cgu.0.rcgu.o.rcgu.o" "foo.adler-67dc86611d2bf020.adler.5bb2de54-cgu.0.rcgu.o.rcgu.o" "foo.alloc-366e8128b0a2151f.alloc.0e2959ea-cgu.0.rcgu.o.rcgu.o" "foo.cfg_if-22b8dcc08139ebd4.cfg_if.4a5ba149-cgu.0.rcgu.o.rcgu.o" "foo.core-0e5c5feeef4bd6da.core.35109205-cgu.0.rcgu.o.rcgu.o" "foo.foo.f94f5f32-cgu.0.rcgu.o" "foo.foo.f94f5f32-cgu.1.rcgu.o" "foo.foo.f94f5f32-cgu.2.rcgu.o" "foo.foo.f94f5f32-cgu.3.rcgu.o" "foo.foo.f94f5f32-cgu.4.rcgu.o" "foo.getopts-7a2ff2879c4becfe.getopts.27ae8826-cgu.0.rcgu.o.rcgu.o" "foo.gimli-281c67c7290209a3.gimli.b3006d85-cgu.0.rcgu.o.rcgu.o" "foo.hashbrown-73dc3622ac20c1ad.hashbrown.4fd96bfe-cgu.0.rcgu.o.rcgu.o" "foo.libc-8e4d63370c2f2f4b.libc.43b5f33f-cgu.0.rcgu.o.rcgu.o" "foo.memchr-4164db77eca254c1.memchr.bf2fc5a0-cgu.0.rcgu.o.rcgu.o" "foo.miniz_oxide-753b0ac42b327310.miniz_oxide.f6d02d85-cgu.0.rcgu.o.rcgu.o" "foo.object-fd18c1e2427b7d66.object.c948ec4e-cgu.0.rcgu.o.rcgu.o" "foo.panic_unwind-cd212035a0d658c8.panic_unwind.b47531a0-cgu.0.rcgu.o.rcgu.o" "foo.rustc_demangle-378d74d608afb5ce.rustc_demangle.15cbba0f-cgu.0.rcgu.o.rcgu.o" "foo.rustc_std_workspace_alloc-0279e801977a0519.rustc_std_workspace_alloc.3d4a570e-cgu.0.rcgu.o.rcgu.o" "foo.rustc_std_workspace_core-043dcb5cef4e65e2.rustc_std_workspace_core.7d396b72-cgu.0.rcgu.o.rcgu.o" "foo.rustc_std_workspace_std-924aa08e8fb30081.rustc_std_workspace_std.cfad5f07-cgu.0.rcgu.o.rcgu.o" "foo.std-67692f6c6473d324.std.14d27bce-cgu.0.rcgu.o.rcgu.o" "foo.std_detect-ac29a076266feb38.std_detect.3a222bf1-cgu.0.rcgu.o.rcgu.o" "foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o" "foo.unicode_width-4cda36558020d9a8.unicode_width.7d30b2de-cgu.0.rcgu.o.rcgu.o" "foo.unwind-d6953a7e39d3701d.unwind.aac5024c-cgu.0.rcgu.o.rcgu.o" "-L" "C:\\Users\\User\\.rustup\\toolchains\\nightly-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib" "-Wl,-Bstatic" "C:\\Users\\User\\.rustup\\toolchains\\nightly-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\libcompiler_builtins-1e8650baf8073116.rlib" "-Wl,-Bdynamic" "-lkernel32" "-lkernel32" "-ladvapi32" "-luserenv" "-lkernel32" "-lws2_32" "-lbcrypt" "-lgcc_eh" "-l:libpthread.a" "-lmsvcrt" "-lmingwex" "-lmingw32" "-lgcc" "-lmsvcrt" "-luser32" "-lkernel32" "-Wl,--nxcompat" "-nostartfiles" "-L" "C:\\Users\\User\\.rustup\\toolchains\\nightly-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib" "-L" "C:\\Users\\User\\.rustup\\toolchains\\nightly-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\self-contained" "-o" "foo.exe" "-Wl,--gc-sections" "-no-pie" "-nodefaultlibs" "C:\\Users\\User\\.rustup\\toolchains\\nightly-x86_64-pc-windows-gnu\\lib\\rustlib\\x86_64-pc-windows-gnu\\lib\\rsend.o"
  = note: foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `core::sync::atomic::atomic_load::h1ce09cb4e3d2295f':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\core\src\sync/atomic.rs:2988: undefined reference to `__imp__ZN3std11collections4hash3map11RandomState3new4KEYS7__getit5__KEY17h4d133909dffb598dE'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `std::sys::windows::thread_local_key::StaticKey::key::h5a360baef9e4385d':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\std\src\sys\windows/thread_local_key.rs:79: undefined reference to `__imp__ZN3std11collections4hash3map11RandomState3new4KEYS7__getit5__KEY17h4d133909dffb598dE'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `core::sync::atomic::atomic_load::h1ce09cb4e3d2295f':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\core\src\sync/atomic.rs:2988: undefined reference to `__imp__ZN3std11collections4hash3map11RandomState3new4KEYS7__getit5__KEY17h4d133909dffb598dE'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `std::sys::windows::thread_local_key::StaticKey::key::h5a360baef9e4385d':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\std\src\sys\windows/thread_local_key.rs:79: undefined reference to `__imp__ZN3std11collections4hash3map11RandomState3new4KEYS7__getit5__KEY17h4d133909dffb598dE'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `std::thread::local::os::Key$LT$T$GT$::try_initialize::ha296643cb4ec4997':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\std\src\thread/local.rs:1118: undefined reference to `__imp__ZN3std11collections4hash3map11RandomState3new4KEYS7__getit5__KEY17h4d133909dffb598dE'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o:/rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\std\src\sys\windows/thread_local_key.rs:79: more undefined references to `__imp__ZN3std11collections4hash3map11RandomState3new4KEYS7__getit5__KEY17h4d133909dffb598dE' follow
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `core::sync::atomic::atomic_load::h1ce09cb4e3d2295f':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\core\src\sync/atomic.rs:2988: undefined reference to `__imp__ZN3std4sync4mpmc5waker17current_thread_id5DUMMY7__getit5__KEY17h1ce21b2969d5bc2bE'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `std::sys::windows::thread_local_key::StaticKey::key::h5a360baef9e4385d':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\std\src\sys\windows/thread_local_key.rs:79: undefined reference to `__imp__ZN3std4sync4mpmc5waker17current_thread_id5DUMMY7__getit5__KEY17h1ce21b2969d5bc2bE'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `core::sync::atomic::atomic_load::h1ce09cb4e3d2295f':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\core\src\sync/atomic.rs:2988: undefined reference to `__imp__ZN3std4sync4mpmc5waker17current_thread_id5DUMMY7__getit5__KEY17h1ce21b2969d5bc2bE'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `std::sys::windows::thread_local_key::StaticKey::key::h5a360baef9e4385d':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\std\src\sys\windows/thread_local_key.rs:79: undefined reference to `__imp__ZN3std4sync4mpmc5waker17current_thread_id5DUMMY7__getit5__KEY17h1ce21b2969d5bc2bE'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `std::thread::local::os::Key$LT$T$GT$::try_initialize::h2eff52084c9a2c81':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\std\src\thread/local.rs:1118: undefined reference to `__imp__ZN3std4sync4mpmc5waker17current_thread_id5DUMMY7__getit5__KEY17h1ce21b2969d5bc2bE'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o:/rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\std\src\sys\windows/thread_local_key.rs:79: more undefined references to `__imp__ZN3std4sync4mpmc5waker17current_thread_id5DUMMY7__getit5__KEY17h1ce21b2969d5bc2bE' follow
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `core::sync::atomic::atomic_load::h1ce09cb4e3d2295f':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\core\src\sync/atomic.rs:2988: undefined reference to `__imp__ZN3std4sync4mpmc7context7Context4with7CONTEXT7__getit5__KEY17h8bce9e2e01c30f57E'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `std::sys::windows::thread_local_key::StaticKey::key::h5a360baef9e4385d':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\std\src\sys\windows/thread_local_key.rs:79: undefined reference to `__imp__ZN3std4sync4mpmc7context7Context4with7CONTEXT7__getit5__KEY17h8bce9e2e01c30f57E'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `core::sync::atomic::atomic_load::h1ce09cb4e3d2295f':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\core\src\sync/atomic.rs:2988: undefined reference to `__imp__ZN3std4sync4mpmc7context7Context4with7CONTEXT7__getit5__KEY17h8bce9e2e01c30f57E'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `std::sys::windows::thread_local_key::StaticKey::key::h5a360baef9e4385d':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\std\src\sys\windows/thread_local_key.rs:79: undefined reference to `__imp__ZN3std4sync4mpmc7context7Context4with7CONTEXT7__getit5__KEY17h8bce9e2e01c30f57E'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o: In function `std::thread::local::os::Key$LT$T$GT$::try_initialize::hc190752f4af349b0':
          /rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\std\src\thread/local.rs:1118: undefined reference to `__imp__ZN3std4sync4mpmc7context7Context4with7CONTEXT7__getit5__KEY17h8bce9e2e01c30f57E'
          foo.test-05c5485ddbae42f3.test.776f7fa2-cgu.0.rcgu.o.rcgu.o:/rustc/70f8737b2f5d3bf7d6b784fad00b663b7ff9feda/library\std\src\sys\windows/thread_local_key.rs:79: more undefined references to `__imp__ZN3std4sync4mpmc7context7Context4with7CONTEXT7__getit5__KEY17h8bce9e2e01c30f57E' follow

  = note: some `extern` functions couldn't be found; some native libraries may need to be installed or have their path specified
  = note: use the `-l` flag to specify native libraries to link
  = note: use the `cargo:rustc-link-lib` directive to specify the native libraries to link with Cargo (see https://doc.rust-lang.org/cargo/reference/build-scripts.html#cargorustc-link-libkindname)

Regression started with #101368.

Meta

rustc --version --verbose:

rustc 1.67.0-nightly (70f8737b2 2022-11-23)
binary: rustc
commit-hash: 70f8737b2f5d3bf7d6b784fad00b663b7ff9feda
commit-date: 2022-11-23
host: x86_64-pc-windows-gnu
release: 1.67.0-nightly
LLVM version: 15.0.4

[thomcc]

This pretty much sucks since it seems like a rustc bug preventing a (admittedly imperfect) soundness fix, but @nikic (#101368 (comment)) and @eddyb (#101368 (comment)) seemed to have a other ideas for how to prevent that issue from happening, so maybe we take the revert here and wait til something can try one of those.

CC @ChrisDenton

[ChrisDenton]

As I said on the revert, I think we do need a proper fix to the underlying issue rather than attempting libs workarounds.

[thomcc]

Hmm, I wonder if we could just do it for target_env = "msvc", since that would at least fix the user's problem in #101368 (comment).

[ChrisDenton]

Maybe. My concern now is that we maybe end up essentially pushing the miscompilation around. So we workaround one problem but maybe we cause another, harder to diagnose, problem somewhere else.

That said, I'm not totally against the idea. Perhaps its a trade off we should make. It doesn't sit particularly well with me though I guess there aren't a lot of good options here.