linker failure on macOS when building Miri: "linker stderr: ld: ignoring duplicate libraries"

[RalfJung]

Miri is failing to build on macOS:

 error: linker stderr: ld: ignoring duplicate libraries: '-liconv', '-lm'
         ld: search path '/Users/runner/work/miri/miri/target/release/build/libffi-sys-2c3f829423e2e4d5/out/libffi-root/lib64' not found
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[4](jemalloc.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[5](arena.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[6](background_thread.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[7](base.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[8](bin.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[9](bin_info.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[10](bitmap.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[11](buf_writer.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[12](cache_bin.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[13](ckh.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[14](counter.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[15](ctl.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[16](decay.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[17](div.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[18](ecache.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[19](edata.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[20](edata_cache.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[21](ehooks.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[22](emap.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[23](eset.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[24](exp_grow.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[25](extent.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[26](extent_dss.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[27](extent_mmap.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[28](fxp.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[29](san.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[30](san_bump.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[31](hook.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[32](hpa.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[33](hpa_hooks.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[34](hpdata.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[35](inspect.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[36](large.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[37](log.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[38](malloc_io.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[39](mutex.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[40](nstime.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[41](pa.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[42](pa_extra.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[43](pai.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[44](pac.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[45](pages.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[47](prof.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[48](prof_data.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[50](prof_recent.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[53](psset.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[54](rtree.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[55](safety_check.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[56](sc.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[57](sec.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[58](stats.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[59](sz.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[60](tcache.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[61](test_hooks.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[62](thread_event.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[63](ticker.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[64](tsd.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[65](witness.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/libtikv_jemalloc_sys-80d1ddce8807bb5c.rlib[66](zone.pic.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/liblibffi_sys-713e5fa4137b14c5.rlib[4](prep_cif.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/liblibffi_sys-713e5fa4137b14c5.rlib[5](types.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/liblibffi_sys-713e5fa4137b14c5.rlib[8](closures.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/liblibffi_sys-713e5fa4137b14c5.rlib[10](ffi.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
         ld: object file (/Users/runner/work/miri/miri/target/release/deps/liblibffi_sys-713e5fa4137b14c5.rlib[11](sysv.o)) was built for newer 'macOS' version (14.5) than being linked (11.0)
    |
    = note: `-D linker-messages` implied by `-D warnings`
    = help: to override `-D warnings` add `#[allow(linker_messages)]`
  error: could not compile `miri` (bin "miri") due to 1 previous error
  error: failed to compile `miri v0.1.0 (/Users/runner/work/miri/miri)`, intermediate artifacts can be found at `/Users/runner/work/miri/miri/target`.
  To reuse those artifacts with a future compilation, set the environment variable `CARGO_TARGET_DIR` to that path.
  Error: command exited with non-zero code `cargo +miri install --locked -Zroot-dir=/Users/runner/work/miri/miri --path /Users/runner/work/miri/miri --force --root /Users/runner/.rustup/toolchains/miri`: 101

Regression range: 814ebca...2f0ad2a

[RalfJung]

Likely caused by #119286

Cc @jyn514 @bjorn3

These errors are entirely un-actionable from my perspective, so while I can add -A linker-messages that feels like just papering over possible issues without understanding anything.

[jyn514]

i am not sure what to tell you. those warnings were already there before, they were just unconditionally silenced instead of being silenced by a lint.

i saw these “duplicate library” warnings in CI when landing the PR and i did not investigate them because there were about a dozen other types of warnings too, and each takes me a couple weeks to track down: #135828

i still think giving you the option between using -A linker-messages and investigating yourself is better than unconditionally silencing the messages.

@rustbot label L-linker_messages

[RalfJung]

I'm not convinced failing my build is the right call here; I asked for Rust warnings to be made errors (which are generally well-documented and understandable), but I didn't ask for inscrutable unactionable linker warnings that apparently do not reflect an actual problem to become hard errors.

[jyn514]

The other option, which I implemented initially, is to make this a hard warning instead of a lint. But that’s worse in other respects, because now you can’t allow it at all. So people will end up with unsilencable warnings when building locally.

I do not think it is a good idea to go back to silencing this unconditionally. In your case the warnings are not useful, but in other cases like #83436, the warnings are very useful and could have helped identify a very tricky bug earlier.

[jyn514]

it does seem like macOS LD is more chatty than other linkers, and if we can find some way to silence these particular warnings you’re getting for everyone, I would be OK with that. But I do not think we should silence all warnings unconditionally, not even if we scope that to macOS.