Duplicate DllMain symbols cause linkage failure using Rust 1.61

[complexspaces]

As of Rust 1.60+, my work codebase no longer compiles correctly when trying to build a workspace package. I believe this may be related to #95604.

Code

I do not yet have a reproduction example as the crate that fails to build is heavy on internal dependencies.

I expected to see this happen: The crate would build correctly.

Instead, this happened: The linker fails with a duplicate DllMain symbol issue.

Version it worked on

It most recently worked on: 1.59

Version with regression

 rustc --version --verbose
rustc 1.61.0 (fe5b13d68 2022-05-18)
binary: rustc
commit-hash: fe5b13d681f25ee6474be29d748c65adcd91f69e
commit-date: 2022-05-18
host: x86_64-pc-windows-msvc
release: 1.61.0
LLVM version: 14.0.0

Link Error

Error

 = note:    Creating library T:\core\target\debug\deps\op_core_bindings.dll.lib and object T:\core\target\debug\deps\op_core_bindings.dll.exp
          libop_windows-45692cb0a6c830a2.rlib(op_windows-45692cb0a6c830a2.43v0ma26l5e2e6rk.rcgu.o) : error LNK2005: DllMain already defined in libcmt.lib(dll_dllmain_stub.obj)
          LINK : warning LNK4199: /DELAYLOAD:CRYPTBASE.DLL ignored; no imports found from CRYPTBASE.DLL
          LINK : warning LNK4199: /DELAYLOAD:NODE.EXE ignored; no imports found from NODE.EXE
          LINK : warning LNK4199: /DELAYLOAD:SECUR32.DLL ignored; no imports found from SECUR32.DLL
          LINK : warning LNK4199: /DELAYLOAD:SSPICLI.DLL ignored; no imports found from SSPICLI.DLL
          LINK : warning LNK4199: /DELAYLOAD:WTSAPI32.dll ignored; no imports found from WTSAPI32.dll
          LINK : warning LNK4199: /DELAYLOAD:tbs.dll ignored; no imports found from tbs.dll
          T:\core\target\debug\deps\op_core_bindings.dll : fatal error LNK1169: one or more multiply defined symbols found

[ChrisDenton]

It most recently worked on: 1.59

So, to be clear, it fails on 1.60? Or did you not test that version?

[complexspaces]

That's my bad, sorry. It also fails with 1.60 with the same error. We did not try using 1.60 (upgrading from 1.59 to 1.61) but I can reproduce the problem with it too. I'll update the issue,

rustc 1.60.0 (7737e0b5c 2022-04-04)
binary: rustc
commit-hash: 7737e0b5c4103216d6fd8cf941b7ab9bdbaace7c
commit-date: 2022-04-04
host: x86_64-pc-windows-msvc
release: 1.60.0
LLVM version: 14.0.0

[complexspaces]

I've been trying to narrow this one down more. I haven't had any success with cargo bisect-rustc yet but this issue does not occur in the latest nightly build:

rustc 1.63.0-nightly (b2eed72a6 2022-05-22)
binary: rustc
commit-hash: b2eed72a6fbf254e7d44942eaa121fcbed05d3fb
commit-date: 2022-05-22
host: x86_64-pc-windows-msvc
release: 1.63.0-nightly
LLVM version: 14.0.4

[complexspaces]

cargo rustc-bisect reports that this issue was fixed by #95604. I still have not had any success finding where it regressed though, sorry.

cargo bisect-rustc -vv --regress=success --preserve --test-dir=./ffi/op-core-bindings --start=1.59.0

...

searched toolchains 02822334e9bd22df33c0692cbaade5a5b5449130 through ef9b49881ba99248b68dbdebbebd50155587c509

********************************************************************************
Regression in 18b53cefdf7456bf68937b08e377b7e622a115c2
********************************************************************************

[inquisitivecrystal]

@complexspaces: since the problem seems to be fixed now and it's hard to pin down in the absence of an MCVE, would you be okay with this being closed?

[complexspaces]

@inquisitivecrystal Yes, I'm fine closing this one since we were unable to extract a minimal reproduction from our codebase.