VxWorks needs a newer version of cc-rs

[BaoshanPang]

Do we have plan to get rid of this restriction recently? A newer version of cc-rs is needed for VxWorks

rust/src/librustc/Cargo.toml

Line 15 in 9e34664

cc = "=1.0.37"

[ehuss]

cc can't currently be updated due to a build problem with riscv. More info at #65445 (comment). I think the issue is that rustbuild uses cc to discover cc toolchains, and cc-rs gained riscv support, and so now it thinks it should use a gcc toolchain that doesn't exist. The detection is in https://github.com/rust-lang/rust/blob/master/src/bootstrap/cc_detect.rs and Alex mentioned just setting a CC_* env var in the riscv container might be enough. It's been on my todo list for a while, but I haven't had a chance to look at it. I can maybe try to look at it this weekend.

[BaoshanPang]

@ehuss
Thanks for working on this issue. Enjoy your weekend, it is not that urgent.