False negative comparing targets with equivalent paths

[JustAPerson]

Imagine a directory structure such as:

├── main.rs
├── target.json
├── libthing/
│   ├── lib.rs

Where main.rs depends on the separate crate thing

cd libthing/ && rustc lib.rs --target ../target.json
rustc main.rs --target target.json --extern  thing=libthing/libthing.rlib

You'll get an error that looks like this:

main.rs:1  error: couldn't find crate `thing` with expected target triple target.json
main.rs:1  extern crate thing;

when compiling main.rs, rustc expects --target ../target.json instead of the equivalent path in the correct working directory.

tl;dr It seems only the exact argument of --target is stored in the .rlib instead of the actual contents of the json file.

[Diggsey]

dup of #24666 ?

[JustAPerson]

Seems so. I'll close in favor of that issue.