Test `ui\abi\stack-probes-lto.rs` fails on Windows-mvsc

[wesleywiser]

I tried this code:

python x.py test --stage 1 src\test\ui\abi

I expected to see all tests pass.

Instead, this happened:

Check compiletest suite=ui mode=ui (x86_64-pc-windows-msvc -> x86_64-pc-windows-msvc)

running 162 tests
i...........i.................i....................iii.............................................. 100/162
..........................F...................................
failures:

---- [ui] ui\abi\stack-probes-lto.rs stdout ----

error: test compilation failed although it shouldn't!
status: exit code: 1
command: PATH="D:\code\rust\build\x86_64-pc-windows-msvc\stage1\bin;C:\Program Files (x86)\Windows Kits\10\bin\x64;C:\Program Files (x86)\Windows Kits\10\bin\10.0.19041.0\x64;C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Tools\MSVC\14.29.30034\bin\HostX64\x64;C:\Program Files\Microsoft Visual Studio\2022\Preview\VC\Tools\MSVC\14.29.30034\bin\HostX64\x64;D:\code\rust\build\x86_64-pc-windows-msvc\stage0-bootstrap-tools\x86_64-pc-windows-msvc\release\deps;D:\code\rust\build\x86_64-pc-windows-msvc\stage0\bin;C:\windows\system32;C:\windows;C:\windows\System32\Wbem;C:\windows\System32\WindowsPowerShell\v1.0\;C:\windows\System32\OpenSSH\;C:\Program Files (x86)\NVIDIA Corporation\PhysX\Common;C:\Program Files\NVIDIA Corporation\NVIDIA NGX;c:\Program Files (x86)\HP\HP Performance Advisor;C:\Program Files\Microsoft SQL Server\130\Tools\Binn\;C:\Program Files (x86)\Windows Kits\10\Windows Performance Toolkit\;C:\WINDOWS\system32;C:\WINDOWS;C:\WINDOWS\System32\Wbem;C:\WINDOWS\System32\WindowsPowerShell\v1.0\;C:\WINDOWS\System32\OpenSSH\;C:\Program Files\Git\cmd;D:\bin;C:\Program Files\CMake\bin;C:\Program Files (x86)\Vim\vim82;" "D:\\code\\rust\\build\\x86_64-pc-windows-msvc\\stage1\\bin\\rustc.exe" "D:\\code\\rust\\src/test\\ui\\abi\\stack-probes-lto.rs" "-Zthreads=1" "--target=x86_64-pc-windows-msvc" "--error-format" "json" "-Ccodegen-units=1" "-Zui-testing" "-Zdeduplicate-diagnostics=no" "-Zemit-future-incompat-report" "-o" "D:\\code\\rust\\build\\x86_64-pc-windows-msvc\\test\\ui\\abi\\stack-probes-lto\\a.exe" "-Crpath" "-O" "-Cdebuginfo=0" "-Lnative=D:\\code\\rust\\build\\x86_64-pc-windows-msvc\\native\\rust-test-helpers" "-C" "lto" "-L" "D:\\code\\rust\\build\\x86_64-pc-windows-msvc\\test\\ui\\abi\\stack-probes-lto\\auxiliary"
stdout:
------------------------------------------

------------------------------------------
stderr:
------------------------------------------
error: linking with `link.exe` failed: exit code: 1120
   |
   = note: "C:\\Program Files\\Microsoft Visual Studio\\2022\\Preview\\VC\\Tools\\MSVC\\14.29.30034\\bin\\HostX64\\x64\\link.exe" "/NOLOGO" "D:\\code\\rust\\build\\x86_64-pc-windows-msvc\\test\\ui\\abi\\stack-probes-lto\\a.stack_probes_lto.7rcbfp3g-cgu.0.rcgu.o" "/LIBPATH:D:\\code\\rust\\build\\x86_64-pc-windows-msvc\\native\\rust-test-helpers" "/LIBPATH:D:\\code\\rust\\build\\x86_64-pc-windows-msvc\\test\\ui\\abi\\stack-probes-lto\\auxiliary" "/LIBPATH:D:\\code\\rust\\build\\x86_64-pc-windows-msvc\\stage1\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib" "/WHOLEARCHIVE:rust_test_helpers.lib" 
"D:\\code\\rust\\build\\x86_64-pc-windows-msvc\\stage1\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib\\libcompiler_builtins-1e28957e3bc2ac25.rlib" "kernel32.lib" "ws2_32.lib" "advapi32.lib" "userenv.lib" "kernel32.lib" "msvcrt.lib" "/NXCOMPAT" "/LIBPATH:D:\\code\\rust\\build\\x86_64-pc-windows-msvc\\stage1\\lib\\rustlib\\x86_64-pc-windows-msvc\\lib" "/OUT:D:\\code\\rust\\build\\x86_64-pc-windows-msvc\\test\\ui\\abi\\stack-probes-lto\\a.exe" "/OPT:REF,ICF" "/DEBUG"
   = note: a.stack_probes_lto.7rcbfp3g-cgu.0.rcgu.o : error LNK2001: unresolved external symbol __rust_panic_type_info
           D:\code\rust\build\x86_64-pc-windows-msvc\test\ui\abi\stack-probes-lto\a.exe : fatal error LNK1120: 1 unresolved externals


error: aborting due to previous error


------------------------------------------



failures:
    [ui] ui\abi\stack-probes-lto.rs

test result: FAILED. 155 passed; 1 failed; 6 ignored; 0 measured; 11835 filtered out; finished in 14.22s

Some tests failed in compiletest suite=ui mode=ui host=x86_64-pc-windows-msvc target=x86_64-pc-windows-msvc

[wesleywiser]

After running a git bisect, it appears this is a result of #81942 (cc @the8472). I can confirm that if I apply the following patch to the failing test, it will succeed:

diff --git a/src/test/ui/abi/stack-probes-lto.rs b/src/test/ui/abi/stack-probes-lto.rs
index 90df1f3f53e..bc3f61248a1 100644
--- a/src/test/ui/abi/stack-probes-lto.rs
+++ b/src/test/ui/abi/stack-probes-lto.rs
@@ -12,7 +12,7 @@
 // ignore-sgx no processes
 // ignore-musl FIXME #31506
 // ignore-pretty
-// compile-flags: -C lto
+// compile-flags: -C lto -Ccodegen-units=4
 // no-prefer-dynamic

 include!("stack-probes.rs");

[the8472]

Most likely a bug that was simply uncovered by the default CGU count change, similar to #84025

[wesleywiser]

That seems likely to me. I'm still trying to figure out why bors isn't failing and yet a clean checkout on Windows does ...

[wesleywiser]

CI sets rust.codegen-units-std=1 and that seems to cause the test to pass.