rust-lang / rust-lang/rust

Clang linker script support - incorrect argument

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Rust
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Description

Using clang as linker with any custom target (spec in json) that contains linker-script (field link-script) produces invocation like

# clang or cc, or gcc
"clang" "--script" "/path/to/link-script/exported/from/my-target-json"

But clang doesn't support --script and returns error clang: error: unsupported option '--script'.
Instead of that, according documentation, we just need to pass it with -T,
e.g.: -T/path/to/link-script.ld.

How to reproduce:

  1. Prepare spec json file for your custom target. It could be anything, just one thing matter - add link-script field. Something like this:

    {
      "llvm-target": "Your-HOST-target",
      "link-script": "ENTRY(main)",
      "linker": "clang"
    }
    
  2. Compile anything targeting to your custom target, e.g.: --target=./your-target.json

Expected result:
Clang should be invoked with -T<link-script> instead of --script <link-script>.

I can reproduce with target-spec with explicitly set linker as clang, gcc, arm-none-eabi-gcc and cc.

Meta

rustc --version --verbose:

rustc 1.80.0-nightly (72fdf913c 2024-06-05)
binary: rustc
commit-hash: 72fdf913c53dd0e75313ba83e4aa80df3f6e2871
commit-date: 2024-06-05
host: aarch64-apple-darwin
release: 1.80.0-nightly
LLVM version: 18.1.6

Contributor guide

Open the contributing guide

First steps

  1. Read the whole issue, then the project's contributing guide.
  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

The payload names no source files or tests; start by locating the target-spec linker argument generation for the link-script field and the handling of clang, gcc, and cc. Reproduce with the custom JSON target described in the issue, then verify that the generated invocation uses the documented -T form and that relevant compiler tests pass.

Written by the indexing model from the issue text.

Assessment

Tech stack
rust
Domain
build-system, compilers
Issue type
Bug
Difficulty
3/5
Estimated time
1-2 days
Activity status
Stale
Clarity
Clearly specified
Newbie friendliness
48/100

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