`cargo-objdump`, `cargo-size`, etc.

[japaric]

Triage

2018-06-29

The llvm-tools rustup component now exists and cargo-binutils is making use of it. Check this announcement for details.

Let's discuss the final UI we want for the Cargo subcommands in the cargo-binutils issue tracker.

---

Once #50 is accepted / implemented it would be nice to have wrapper over e.g. llvm-objdump for
convenience. The wrapper would take care of passing -triple=$target to llvm-objdump, demangling
the output, passing the path to the binary to llvm-objdump, etc.

We don't have to wait until #50 is implemented though; we can start prototyping on top of
arm-none-eabi-objdump.

Tasks

• Define what kind of user interface we want. To be done in the cargo-binutils repository.

• Prototype cargo-objdump, cargo-size, etc. on top of arm-none-eabi binutils

• Make cargo-objdump et al. use LLVM binutils once Ship llvm binutils with the Rust toolchain #50 is implemented.

Originally discussed in #43 but I think this more in line with #44

cc @thejpster

[japaric]

Adding to the epoch 2018 milestone as discussed in yesterday's meeting

[dvc94ch]

Can we also add cargo-dwarfdump [0]

[0] https://llvm.org/docs/CommandGuide/llvm-dwarfdump.html

[whitequark]

When was the last time you needed dwarfdump and were not developing an LLVM backend?..

[grossws]

@m4b wrote cargo-sym which can be used as limited objdump replacement.

[japaric]

@dvc94ch I didn't include that tool in the discussion issue I opened (rust-lang/rust#49584). You can bring it up in the comments.

During yesterday's meeting @jcsoo brought up the idea of having a step 0 for these subcommands: a minimal implementation could simply proxy the LLVM tool; for example, cargo nm -- -C path/to/binary would be sugar for $(rustc --print sysroot)/path/to/llvm-nm -C path/to/binary.

[whitequark]

@m4b wrote cargo-sym which can be used as limited objdump replacement.

Please, no. This would mean that e.g. the OpenRISC LLVM/rustc port that I maintain would be gated on Capstone gaining OpenRISC support before standard rustc tools could be used.

[japaric]

During yesterday's meeting @jcsoo brought up the idea of having a step 0 for these subcommands: a minimal implementation could simply proxy the LLVM tool

I have implemented step 0 in https://github.com/japaric/cargo-binutils

[japaric]

The llvm-tools rustup component now exists and cargo-binutils is making use of it. Check this announcement for details.

Let's discuss the final UI we want for the Cargo subcommands in the cargo-binutils issue tracker.