Use the selected CC/CXX in crates that build with gcc-rs.

[bryant]

Such as librustc_llvm.

[rust-highfive]

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[aidanhs]

r? @alexcrichton

Thanks for the PR @bryant, we'll check in every now and again to make sure @alexcrichton or another reviewer gets to this soon!

[alexcrichton]

Thanks for the PR! These should already be set though for various scripts, but are they not working?

[bryant]

They aren't. Without this patch, the librustc_llvm attempts to invoke cc regardless of config.toml. There is no cc on my system, so the build simply halts.

…

On May 24, 2017 11:08 PM, "Alex Crichton" ***@***.***> wrote: Thanks for the PR! These should already be set though <https://github.com/rust-lang/rust/blob/5b13bff5203c1bdc6ac6dc87f69b5359a9503078/src/bootstrap/lib.rs#L470-L472> for various scripts, but are they not working? — You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub <#42206 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AAo8b3b7nHZATYPOAtANAo5JSRkTkyStks5r9PC5gaJpZM4NlwyU> .

[alexcrichton]

Can you gist the error message you're seeing? The build script is using the gcc crate which should be using the preexisting env vars.

[aidanhs]

Hi @bryant, any news on the gist with the error? It'd be good to fix whatever you saw!

[hanna-kruppe]

I think I encountered this issue too. I rebuilt LLVM with clang instead of GCC (= cc for me) and put cc = "clang" and cxx = "clang++" in config.toml, my builds are failing because of the mismatched compiler ( even after x.py clean). Gist with build script output here: https://gist.github.com/rkruppe/a83d1509c4440917a2be37f3742b67ad

[alexcrichton]

Ah it looks like setting CXX is missing here

[bryant]

Sorry for not being clear initially. The rustc_llvm problem that prompted this patch was a link failure: cargo or rustc or whatever insists on invoking cc as the linker.

Ah it looks like setting CXX is missing here

Unless gcc-rs calls CXX to link, I'm not sure that that's the problem. I'll try again tonight with CXX added at that spot.

[aidanhs]

@bryant did you manage to take another look at this?

[alexcrichton]

Ok I'm going to close this due to inactivity, but thanks regardless for the PR @bryant! Feel free to resubmit as a new PR!