force rebuild if memory.x changed

[obraunsdorf]

No description provided.

[rust-highfive]

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[therealprof]

I don't think that's sufficient. Usually the file looks like:

use std::env; use std::fs::File; use std::io::Write; use std::path::PathBuf; fn main() { // Put the linker script somewhere the linker can find it let out = &PathBuf::from(env::var_os("OUT_DIR").unwrap()); File::create(out.join("memory.x")) .unwrap() .write_all(include_bytes!("memory.x")) .unwrap(); println!("cargo:rustc-link-search={}", out.display()); println!("cargo:rerun-if-changed=build.rs"); println!("cargo:rerun-if-changed=memory.x"); } 

[adamgreig]

By default the linker will search the crate's directory without needing to be told, so having memory.x in the same place as Cargo.toml works fine; adding a build.rs which only adds cargo:rerun-if-changed=memory.x is enough to rerun the build when memory.x changes in that case. Whether we want/should (re)include that longer build.rs example in the quickstart, I don't know... the only edge case where it can be required is in workspaces or weird build configurations.

[therealprof]

I'm not sure where the more elaborate build.rs is coming from. Also I don't see too much value in a build.rs in general but if we have one it should probably provide the full benefit and not just half. Are there any downsides to providing the full version?

[thalesfragoso]

I'm not sure where the more elaborate build.rs is coming from. Also I don't see too much value in a build.rs in general but if we have one it should probably provide the full benefit and not just half. Are there any downsides to providing the full version?

I always use the complex one, but some people did some testing and it seems that the cargo directory is already in the linker search path, so it's unnecessary to copy it somewhere else.

[therealprof]

As discussed in the meeting we should add a comment to explain when and why this might be necessary to give users a good base for a decision whether this is necessary.

[therealprof]

Addressed by #92.