How to get the linker to produce a map file using Cargo

Question

I'm writing a Rust program targeted for an STM32F407 processor using zinc. I'd like to be able to produce a linker map file. I've found that I can put the following in my main.rs and this gives me the desired result:

#![feature(link_args)]
#[link_args = "-Wl,-Map=blink_stm32f4.map"]
extern {}

However, the documentation for link_args suggests not to use this method.

What other methods exist to get the linker to produce a map file?

Answer 1

link-args is possible to pass to rustc via rustc -C link-args="-Wl,-Map=blink_stm32f4.map" test.rs.

And there is option of cargo rustflags in build section. See cargo config. It works like this:

$ cargo new --bin testbin
$ cd testbin
$ cat .cargo/config 
[build]
rustflags = ["-Clink-args=-Wl,-Map=/tmp/blink_f7.map"]
$ cargo build

Also there is linker option in cargo config. I don't try to pass via this option gcc plus flags, only gcc, but you can write gcc wrapper script like:

$ cat my-linker.sh
#!/bin/sh

arm-...-gcc -Wl,-Map=blink_stm32f4.map $@